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foundationdb/fdbserver/KeyValueStoreSQLite.actor.cpp

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/*
* KeyValueStoreSQLite.actor.cpp
*
* This source file is part of the FoundationDB open source project
*
* Copyright 2013-2018 Apple Inc. and the FoundationDB project authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define SQLITE_THREADSAFE 0 // also in sqlite3.amalgamation.c!
#include "fdbrpc/crc32c.h"
#include "fdbserver/IKeyValueStore.h"
#include "fdbserver/CoroFlow.h"
#include "fdbserver/Knobs.h"
#include "flow/Hash3.h"
extern "C" {
#include "fdbserver/sqlite/sqliteInt.h"
u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
}
#include "flow/ThreadPrimitives.h"
#include "fdbserver/template_fdb.h"
#include "fdbrpc/simulator.h"
#include "flow/actorcompiler.h" // This must be the last #include.
#if SQLITE_THREADSAFE == 0
#define sqlite3_mutex_enter(x)
#define sqlite3_mutex_leave(x)
#endif
void hexdump(FILE *fout, StringRef val);
/*#undef state
#include <Windows.h>*/
/*uint64_t getFileSize( const char* filename ) {
HANDLE f = CreateFile( filename, GENERIC_READ, FILE_SHARE_READ|FILE_SHARE_WRITE|FILE_SHARE_DELETE, NULL, OPEN_EXISTING, 0, NULL);
if (f == INVALID_HANDLE_VALUE) return 0;
DWORD hi,lo;
lo = GetFileSize(f, &hi);
CloseHandle(f);
return (uint64_t(hi)<<32) + lo;
}*/
struct SpringCleaningStats {
int64_t springCleaningCount;
int64_t lazyDeletePages;
int64_t vacuumedPages;
double springCleaningTime;
double vacuumTime;
double lazyDeleteTime;
SpringCleaningStats() : springCleaningCount(0), lazyDeletePages(0), vacuumedPages(0), springCleaningTime(0.0), vacuumTime(0.0), lazyDeleteTime(0.0) {}
};
struct PageChecksumCodec {
PageChecksumCodec(std::string const &filename) : pageSize(0), reserveSize(0), filename(filename), silent(false) {}
int pageSize;
int reserveSize;
std::string filename;
bool silent;
struct SumType {
bool operator==(const SumType &rhs) const { return part1 == rhs.part1 && part2 == rhs.part2; }
uint32_t part1;
uint32_t part2;
std::string toString() { return format("0x%08x%08x", part1, part2); }
};
// Calculates and then either stores or verifies a checksum.
// The checksum is read/stored at the end of the page buffer.
// Page size is passed in as pageLen because this->pageSize is not always appropriate.
// If write is true then the checksum is written into the page and true is returned.
// If write is false then the checksum is compared to the in-page sum and the return value
// is whether or not the checksums were equal.
bool checksum(Pgno pageNumber, void *data, int pageLen, bool write) {
ASSERT(pageLen > sizeof(SumType));
char *pData = (char *)data;
int dataLen = pageLen - sizeof(SumType);
SumType *pSumInPage = (SumType *)(pData + dataLen);
if (write) {
// Always write a CRC32 checksum for new pages
pSumInPage->part1 = 0; // Indicates CRC32 is being used
pSumInPage->part2 = crc32c_append(0xfdbeefdb, static_cast<uint8_t*>(data), dataLen);
return true;
}
SumType sum;
if (pSumInPage->part1 == 0) {
// part1 being 0 indicates with high probability that a CRC32 checksum
// was used, so check that first. If this checksum fails, there is still
// some chance the page was written with hashlittle2, so fall back to checking
// hashlittle2
sum.part1 = 0;
sum.part2 = crc32c_append(0xfdbeefdb, static_cast<uint8_t*>(data), dataLen);
if (sum == *pSumInPage) return true;
}
SumType hashLittle2Sum;
hashLittle2Sum.part1 = pageNumber; // DO NOT CHANGE
hashLittle2Sum.part2 = 0x5ca1ab1e;
hashlittle2(pData, dataLen, &hashLittle2Sum.part1, &hashLittle2Sum.part2);
if (hashLittle2Sum == *pSumInPage) return true;
if (!silent) {
TraceEvent trEvent(SevError, "SQLitePageChecksumFailure");
trEvent.error(checksum_failed())
.detail("CodecPageSize", pageSize)
.detail("CodecReserveSize", reserveSize)
.detail("Filename", filename)
.detail("PageNumber", pageNumber)
.detail("PageSize", pageLen)
.detail("ChecksumInPage", pSumInPage->toString())
.detail("ChecksumCalculatedHL2", hashLittle2Sum.toString());
if (pSumInPage->part1 == 0) trEvent.detail("ChecksumCalculatedCRC", sum.toString());
}
return false;
}
static void * codec(void *vpSelf, void *data, Pgno pageNumber, int op) {
PageChecksumCodec *self = (PageChecksumCodec *)vpSelf;
// Page write operations are 6 for DB page and 7 for journal page
bool write = (op == 6 || op == 7);
// Page read is operation 3, which must be the operation if it's not a write.
ASSERT(write || op == 3);
// Page 1 is special. It contains the database configuration including Page Size and Reserve Size.
// SQLite can't get authoritative values for these things until the Pager Codec has validated (and
// potentially decrypted) Page 1 itself, so it can't tell the Pager Codec what those things are before
// Page 1 is handled. It will guess a Page Size of SQLITE_DEFAULT_PAGE_SIZE, and a Reserve Size based
// on the pre-verified (and perhaps still encrypted) header in the Page 1 data that it will then pass
// to the Pager Codec.
//
// So, Page 1 must be written and verifiable as a SQLITE_DEFAULT_PAGE_SIZE sized page as well as
// the actual configured page size for the database, if it is larger. A configured page size lower
// than the default (in other words 512) results in undefined behavior.
if(pageNumber == 1) {
if(write && self->pageSize > SQLITE_DEFAULT_PAGE_SIZE) {
self->checksum(pageNumber, data, SQLITE_DEFAULT_PAGE_SIZE, write);
}
}
else {
// For Page Numbers other than 1, reserve size must be the size of the checksum.
if(self->reserveSize != sizeof(SumType)) {
if(!self->silent)
TraceEvent(SevWarnAlways, "SQLitePageChecksumFailureBadReserveSize")
.detail("CodecPageSize", self->pageSize)
.detail("CodecReserveSize", self->reserveSize)
.detail("Filename", self->filename)
.detail("PageNumber", pageNumber);
return NULL;
}
}
if(!self->checksum(pageNumber, data, self->pageSize, write))
return NULL;
return data;
}
static void sizeChange(void *vpSelf, int new_pageSize, int new_reserveSize) {
PageChecksumCodec *self = (PageChecksumCodec *)vpSelf;
self->pageSize = new_pageSize;
self->reserveSize = new_reserveSize;
}
static void free(void *vpSelf) {
PageChecksumCodec *self = (PageChecksumCodec *)vpSelf;
delete self;
}
};
struct SQLiteDB : NonCopyable {
std::string filename;
sqlite3* db;
Btree* btree;
int table, freetable;
bool haveMutex;
Reference<IAsyncFile> dbFile, walFile;
bool page_checksums;
bool fragment_values;
PageChecksumCodec *pPagerCodec; // we do NOT own this pointer, db does.
void beginTransaction(bool write) {
checkError("BtreeBeginTrans", sqlite3BtreeBeginTrans(btree, write));
}
void endTransaction() {
checkError("BtreeCommit", sqlite3BtreeCommit(btree));
}
void rollback() {
checkError("BtreeRollback", sqlite3BtreeRollback(btree));
}
void open(bool writable);
void createFromScratch();
SQLiteDB( std::string filename, bool page_checksums, bool fragment_values): filename(filename), db(NULL), btree(NULL), table(-1), freetable(-1), haveMutex(false), page_checksums(page_checksums), fragment_values(fragment_values) {}
~SQLiteDB() {
if (db) {
if (haveMutex) {
sqlite3_mutex_leave(db->mutex);
}
sqlite3_close( db );
}
}
void initPagerCodec() {
if(page_checksums) {
int r = sqlite3_test_control(SQLITE_TESTCTRL_RESERVE, db, sizeof(PageChecksumCodec::SumType));
if(r != 0) {
TraceEvent(SevError, "BtreePageReserveSizeSetError").detail("Filename", filename).detail("ErrorCode", r);
ASSERT(false);
}
// Always start with a new pager codec with default options.
pPagerCodec = new PageChecksumCodec(filename);
sqlite3BtreePagerSetCodec(btree, PageChecksumCodec::codec, PageChecksumCodec::sizeChange, PageChecksumCodec::free, pPagerCodec);
}
}
void checkError( const char* context, int rc ) {
//if (deterministicRandom()->random01() < .001) rc = SQLITE_INTERRUPT;
if (rc) {
// Our exceptions don't propagate through sqlite, so we don't know for sure if the error that caused this was
// an injected fault. Assume that if fault injection is happening, this is an injected fault.
Error err = io_error();
if (g_network->isSimulated() && (g_simulator.getCurrentProcess()->fault_injection_p1 || g_simulator.getCurrentProcess()->machine->machineProcess->fault_injection_p1 || g_simulator.getCurrentProcess()->rebooting))
err = err.asInjectedFault();
if (db)
db->errCode = rc;
if (rc == SQLITE_NOMEM) platform::outOfMemory(); // SOMEDAY: Trap out of memory errors at allocation time; check out different allocation options in sqlite
TraceEvent(SevError, "DiskError").error(err).detail("In", context).detail("File", filename).detail("SQLiteError", sqlite3ErrStr(rc)).detail("SQLiteErrorCode", rc).GetLastError();
throw err;
}
}
void checkpoint( bool restart ) {
int logSize=0, checkpointCount=0;
//double t = timer();
while (true) {
int rc = sqlite3_wal_checkpoint_v2(db, 0, restart ? SQLITE_CHECKPOINT_RESTART : SQLITE_CHECKPOINT_FULL, &logSize, &checkpointCount);
if (!rc) break;
if ((sqlite3_errcode(db)&0xff) == SQLITE_BUSY) {
//printf("#");
//threadSleep(.010);
sqlite3_sleep(10);
} else
checkError("checkpoint", rc);
}
//printf("Checkpoint (%0.1f ms): %d frames in log, %d checkpointed\n", (timer()-t)*1000, logSize, checkpointCount);
}
uint32_t freePages() {
u32 fp = 0;
sqlite3BtreeGetMeta(btree, BTREE_FREE_PAGE_COUNT, &fp);
return fp;
}
bool vacuum() { // Returns true if vacuum is complete or stalled by a lazy free root
int rc = sqlite3BtreeIncrVacuum(btree);
if (rc && rc != SQLITE_DONE) checkError("vacuum", rc);
return rc == SQLITE_DONE;
}
int check(bool verbose) {
int errors = 0;
int tables[] = {1, table, freetable};
TraceEvent("BTreeIntegrityCheckBegin").detail("Filename", filename);
char* e = sqlite3BtreeIntegrityCheck(btree, tables, 3, 1000, &errors, verbose);
if (!(g_network->isSimulated() && (g_simulator.getCurrentProcess()->fault_injection_p1 || g_simulator.getCurrentProcess()->rebooting))) {
TraceEvent((errors||e) ? SevError : SevInfo, "BTreeIntegrityCheckResults").detail("Filename", filename).detail("ErrorTotal", errors);
if(e != nullptr) {
// e is a string containing 1 or more lines. Create a separate trace event for each line.
char *lineStart = e;
while(lineStart != nullptr) {
char *lineEnd = strstr(lineStart, "\n");
if(lineEnd != nullptr) {
*lineEnd = '\0';
++lineEnd;
}
// If the line length found is not zero then print a trace event
if(*lineStart != '\0')
TraceEvent(SevError, "BTreeIntegrityCheck").detail("Filename", filename).detail("ErrorDetail", lineStart);
lineStart = lineEnd;
}
}
TEST(true); // BTree integrity checked
}
if (e) sqlite3_free(e);
return errors;
}
int checkAllPageChecksums();
};
class Statement : NonCopyable {
SQLiteDB& db;
sqlite3_stmt *stmt;
public:
Statement( SQLiteDB& db, const char* sql )
: db(db), stmt(NULL)
{
db.checkError("prepare", sqlite3_prepare_v2( db.db, sql, -1, &stmt, NULL));
}
~Statement() {
try {
db.checkError("finalize", sqlite3_finalize( stmt ));
} catch (...) {
}
}
Statement& reset() {
db.checkError("reset", sqlite3_reset(stmt));
return *this;
}
Statement& param(int i, StringRef value) {
db.checkError("bind", sqlite3_bind_blob( stmt, i, value.begin(), value.size(), SQLITE_STATIC ));
return *this;
}
Statement& param(int i, int value) {
db.checkError("bind", sqlite3_bind_int( stmt, i, value ));
return *this;
}
Statement& execute() {
int r = sqlite3_step( stmt );
if (r == SQLITE_ROW) db.checkError("execute called on statement that returns rows", r);
if (r != SQLITE_DONE) db.checkError("execute", r);
return *this;
}
bool nextRow() {
int r = sqlite3_step( stmt );
if (r == SQLITE_ROW) return true;
if (r == SQLITE_DONE) return false;
db.checkError( "nextRow", r );
__assume(false); // NOT REACHED
}
StringRef column( int i ) {
return StringRef(
(const uint8_t*)sqlite3_column_blob(stmt, i),
sqlite3_column_bytes(stmt, i) );
}
};
void hexdump(FILE *fout, StringRef val) {
int buflen = val.size();
const unsigned char *buf = val.begin();
int i, j;
for (i=0; i<buflen; i+=32) {
fprintf(fout, "%06x: ", i);
for (j=0; j<32; j++) {
if(j == 16)
fprintf(fout, " ");
if (i+j < buflen)
fprintf(fout, "%02x ", buf[i+j]);
else
fprintf(fout, " ");
}
fprintf(fout, " ");
for (j=0; j<32; j++) {
if(j == 16)
fprintf(fout, " ");
if (i+j < buflen)
fprintf(fout, "%c", isprint(buf[i+j]) ? buf[i+j] : '.');
}
fprintf(fout, "\n");
}
}
Value encode( KeyValueRef kv ) {
int keyCode = kv.key.size()*2 + 12;
int valCode = kv.value.size()*2 + 12;
int header_size = sqlite3VarintLen(keyCode) + sqlite3VarintLen(valCode);
int hh = sqlite3VarintLen(header_size);
header_size += hh;
if (hh < sqlite3VarintLen(header_size))
header_size++;
int size = header_size + kv.key.size() + kv.value.size();
Value v;
uint8_t* d = new (v.arena()) uint8_t[size];
((ValueRef&)v) = KeyRef(d, size);
d += sqlite3PutVarint( d, header_size );
d += sqlite3PutVarint( d, keyCode );
d += sqlite3PutVarint( d, valCode );
memcpy(d, kv.key.begin(), kv.key.size());
d += kv.key.size();
memcpy(d, kv.value.begin(), kv.value.size());
d += kv.value.size();
ASSERT( d == v.begin()+size );
return v;
}
// Fragments are encoded as (key, index, value) tuples
// An index of 0 indicates an unfragmented KV pair.
// For fragmented KV pairs, the values will be concatenated in index order.
//
// In the current implementation, index values are chosen to enable a single linear
// pass over the fragments, in forward or backward order, to immediately know the final
// unfragmented value size accurately enough to allocate a buffer that is certainly large
// enough to hold the defragmented bytes.
//
// However, the decoder could be made to work if these index value 'hints' become inaccurate
// due to a change in splitting logic or index numbering. The decoder would just have to support
// buffer expansion as needed.
//
// Note that changing the following value constitutes a change in index numbering.
#define KV_FRAGMENT_INDEX_SIZE_HINT_FACTOR 4
Value encodeKVFragment( KeyValueRef kv, uint32_t index) {
int keyCode = kv.key.size()*2 + 12;
int valCode = kv.value.size()*2 + 12;
// The SQLite type code for the index is the minimal number of bytes needed to store
// a signed representation of the index value. The type code for 0 is 0 (which is
// actually the null type in SQLite).
int8_t indexCode = 0;
if (index != 0) {
uint32_t tmp = index;
while (tmp != 0) {
++indexCode;
tmp >>= 8;
}
// An increment is required if the high bit of the N-byte index value is set, since it is
// positive number but SQLite only stores signed values and would interpret it as negative.
if (index >> (8 * indexCode - 1)) ++indexCode;
}
int header_size = sqlite3VarintLen(keyCode) + sizeof(indexCode) + sqlite3VarintLen(valCode);
int hh = sqlite3VarintLen(header_size);
header_size += hh;
if (hh < sqlite3VarintLen(header_size))
header_size++;
int size = header_size + kv.key.size() + indexCode + kv.value.size();
Value v;
uint8_t* d = new (v.arena()) uint8_t[size];
((ValueRef&)v) = KeyRef(d, size);
d += sqlite3PutVarint( d, header_size );
d += sqlite3PutVarint( d, keyCode );
*d++ = indexCode;
d += sqlite3PutVarint( d, valCode );
// Write key
memcpy(d, kv.key.begin(), kv.key.size());
d += kv.key.size();
// Write index bytes, if any
for(int i = indexCode - 1; i >= 0; --i) {
d[i] = (uint8_t)index;
index >>= 8;
}
d += indexCode;
// Write value
memcpy(d, kv.value.begin(), kv.value.size());
d += kv.value.size();
ASSERT( d == v.begin()+size );
return v;
}
int getEncodedSize( int keySize, int valuePrefixSize ) {
int keyCode = keySize*2 + 12;
int header_size = sqlite3VarintLen(keyCode) + 8; // 8 is the maximum return value of sqlite3VarintLen(), so this is our worst case header size (for values larger than allowable database values)
int hh = sqlite3VarintLen(header_size);
header_size += hh;
if (hh < sqlite3VarintLen(header_size))
header_size++;
return header_size + keySize + valuePrefixSize;
}
KeyValueRef decodeKV( StringRef encoded) {
uint8_t const* d = encoded.begin();
uint64_t h, len1, len2;
d += sqlite3GetVarint( d, (u64*)&h );
d += sqlite3GetVarint( d, (u64*)&len1 );
d += sqlite3GetVarint( d, (u64*)&len2 );
ASSERT( d == encoded.begin() + h );
ASSERT( len1 >= 12 && !(len1&1) );
ASSERT( len2 >= 12 && !(len2&1) );
len1 = (len1-12)/2;
len2 = (len2-12)/2;
ASSERT( d + len1 + len2 == encoded.end() );
return KeyValueRef( KeyRef(d, len1), KeyRef(d+len1, len2) );
}
// Given a key size and value prefix size, get the minimum bytes that must be read from the underlying
// btree tuple to safely read the prefix length from the value bytes (if the value is long enough)
int getEncodedKVFragmentSize( int keySize, int valuePrefixSize ) {
int keyCode = keySize*2 + 12;
int header_size = sqlite3VarintLen(keyCode)
+ 1 // index code length
+ 8; // worst case for value size (larger than fdb api allows)
int hh = sqlite3VarintLen(header_size);
header_size += hh;
if (hh < sqlite3VarintLen(header_size))
header_size++;
return header_size + keySize
+ 4 // Max width allowed of index value
+ valuePrefixSize;
}
// Decode (key, index, value) tuple.
// A present() Optional will always be returned UNLESS partial is true.
// If partial is true then the return will not be present() unless at least
// the full key and index were in the encoded buffer. The value returned will be 0 or
// more value bytes, however many were available.
// Note that a short encoded buffer must at *least* contain the header length varint.
Optional<KeyValueRef> decodeKVFragment( StringRef encoded, uint32_t *index = NULL, bool partial = false) {
uint8_t const* d = encoded.begin();
uint64_t h, len1, len2;
d += sqlite3GetVarint( d, (u64*)&h );
// Make sure entire header is present, else return nothing
if(partial && encoded.size() < h)
return Optional<KeyValueRef>();
d += sqlite3GetVarint( d, (u64*)&len1 );
const uint8_t indexLen = *d++;
ASSERT(indexLen <= 4);
d += sqlite3GetVarint( d, (u64*)&len2 );
ASSERT( d == encoded.begin() + h );
ASSERT( len1 >= 12 && !(len1&1) );
ASSERT( len2 >= 12 && !(len2&1) );
len1 = (len1-12)/2;
len2 = (len2-12)/2;
if(partial) {
// If the key and index aren't complete, return nothing.
if(d + len1 + indexLen > encoded.end())
return Optional<KeyValueRef>();
// Encoded size shouldn't be *larger* than the record described by the header no matter what.
ASSERT( d + len1 + indexLen + len2 >= encoded.end() );
// Shorten value length to be whatever bytes remain after the header/key/index
len2 = std::min(len2, (uint64_t)(encoded.end() - indexLen - len1 - d));
}
else {
// But for non partial records encoded size should be exactly the size of the described record.
ASSERT( d + len1 + indexLen + len2 == encoded.end() );
}
// Decode big endian index
if(index != nullptr) {
if(indexLen == 0)
*index = 0;
else {
const uint8_t *begin = d + len1;
const uint8_t *end = begin + indexLen;
*index = (uint8_t)*begin++;
while(begin < end) {
*index <<= 8;
*index |= *begin++;
}
}
}
return KeyValueRef( KeyRef(d, len1), KeyRef(d+len1+indexLen, len2) );
}
KeyValueRef decodeKVPrefix( StringRef encoded, int maxLength ) {
uint8_t const* d = encoded.begin();
uint64_t h, len1, len2;
d += sqlite3GetVarint( d, (u64*)&h );
d += sqlite3GetVarint( d, (u64*)&len1 );
d += sqlite3GetVarint( d, (u64*)&len2 );
ASSERT( d == encoded.begin() + h );
ASSERT( len1 >= 12 && !(len1&1) );
ASSERT( len2 >= 12 && !(len2&1) );
len1 = (len1-12)/2;
len2 = (len2-12)/2;
len2 = std::min(len2, (uint64_t)maxLength);
ASSERT( d + len1 + len2 <= encoded.end() );
return KeyValueRef( KeyRef(d, len1), KeyRef(d+len1, len2) );
}
Value encodeKey( KeyRef key, bool using_fragments) {
int keyCode = key.size()*2 + 12;
int header_size = sqlite3VarintLen(keyCode);
if(using_fragments) // will be encoded as key, 0 (where 0 is really a null)
++header_size;
int hh = sqlite3VarintLen(header_size);
header_size += hh;
if (hh < sqlite3VarintLen(header_size))
header_size++;
int size = header_size + key.size();
Value v;
uint8_t* d = new (v.arena()) uint8_t[size];
((ValueRef&)v) = KeyRef(d, size);
d += sqlite3PutVarint( d, header_size );
d += sqlite3PutVarint( d, keyCode );
if(using_fragments)
*d++ = 0;
memcpy(d, key.begin(), key.size());
d += key.size();
ASSERT( d == v.begin()+size );
return v;
}
struct SQLiteTransaction {
SQLiteDB& db;
bool shouldCommit;
SQLiteTransaction(SQLiteDB& db, bool write) : db(db), shouldCommit(false) {
db.beginTransaction(write);
}
void commit() {
shouldCommit = true;
}
~SQLiteTransaction() {
try {
if (shouldCommit)
db.endTransaction();
else
db.rollback();
} catch (...) {}
}
};
struct IntKeyCursor {
SQLiteDB& db;
BtCursor *cursor;
IntKeyCursor( SQLiteDB& db, int table, bool write ) : cursor(0), db(db) {
cursor = (BtCursor*)new char[sqlite3BtreeCursorSize()];
sqlite3BtreeCursorZero(cursor);
db.checkError("BtreeCursor", sqlite3BtreeCursor(db.btree, table, write, NULL, cursor));
}
~IntKeyCursor() {
if (cursor) {
try {
db.checkError("BtreeCloseCursor", sqlite3BtreeCloseCursor(cursor));
} catch (...) {}
delete[] (char*)cursor;
}
}
};
struct RawCursor {
SQLiteDB& db;
BtCursor *cursor;
KeyInfo keyInfo;
bool valid;
operator bool() const { return valid; }
RawCursor( SQLiteDB& db, int table, bool write) : cursor(0), db(db), valid(false) {
keyInfo.db = db.db;
keyInfo.enc = db.db->aDb[0].pSchema->enc;
keyInfo.aColl[0] = db.db->pDfltColl;
keyInfo.aSortOrder = 0;
keyInfo.nField = 1;
try {
cursor = (BtCursor*)new char[sqlite3BtreeCursorSize()];
sqlite3BtreeCursorZero(cursor);
db.checkError("BtreeCursor", sqlite3BtreeCursor(db.btree, table, write, &keyInfo, cursor));
} catch (...) {
destroyCursor();
throw;
}
}
~RawCursor() {
destroyCursor();
}
void destroyCursor() {
if (cursor) {
try {
db.checkError("BtreeCloseCursor", sqlite3BtreeCloseCursor(cursor));
} catch (...) {
TraceEvent(SevError,"RawCursorDestructionError");
}
delete[] (char*)cursor;
}
}
void moveFirst() {
int empty=1;
db.checkError("BtreeFirst", sqlite3BtreeFirst(cursor, &empty));
valid = !empty;
}
void moveNext() {
int empty=1;
db.checkError("BtreeNext", sqlite3BtreeNext(cursor, &empty));
valid = !empty;
}
void movePrevious() {
int empty=1;
db.checkError("BtreePrevious", sqlite3BtreePrevious(cursor, &empty));
valid = !empty;
}
int size() {
int64_t size;
db.checkError("BtreeKeySize", sqlite3BtreeKeySize(cursor, (i64*)&size));
ASSERT( size < (1<<30) );
return size;
}
Value getEncodedRow() {
int s = size();
Value v;
uint8_t* d = new (v.arena()) uint8_t[s];
db.checkError("BtreeKey", sqlite3BtreeKey(cursor, 0, s, d));
((ValueRef&)v) = KeyRef(d, s);
return v;
}
ValueRef getEncodedRow( Arena& arena ) {
int s = size();
uint8_t* d = new (arena) uint8_t[s];
db.checkError("BtreeKey", sqlite3BtreeKey(cursor, 0, s, d));
return KeyRef(d, s);
}
ValueRef getEncodedRowPrefix( Arena& arena, int maxEncodedSize ) {
int s = std::min(size(), maxEncodedSize);
uint8_t* d = new (arena) uint8_t[s];
db.checkError("BtreeKey", sqlite3BtreeKey(cursor, 0, s, d));
return KeyRef(d, s);
}
void insertFragment( KeyValueRef kv, uint32_t index, int seekResult ) {
Value v = encodeKVFragment(kv, index);
db.checkError("BtreeInsert", sqlite3BtreeInsert(cursor, v.begin(), v.size(), NULL, 0, 0, 0, seekResult));
}
void remove() {
db.checkError("BtreeDelete", sqlite3BtreeDelete(cursor));
}
void set( KeyValueRef kv ) {
if(db.fragment_values) {
// Unlike a read, where we need to access fragments in fully forward or reverse order,
// here we just want to delete any existing fragments for the key. It does not matter
// what order we delete them in, and SQLite requires us to seek after every delete, so
// the fastest way to do this is to repeatedly seek to the tuple prefix (key, ) and
// delete the current fragment until nothing is there.
// This should result in almost identical performance to non-fragmenting mode for single fragment kv pairs.
int seekResult = moveTo(kv.key, true); // second arg means to ignore fragmenting and seek to (key, )
while(seekResult == 0) {
remove();
seekResult = moveTo(kv.key, true);
}
const int primaryPageUsable = SERVER_KNOBS->SQLITE_FRAGMENT_PRIMARY_PAGE_USABLE;
const int overflowPageUsable = SERVER_KNOBS->SQLITE_FRAGMENT_OVERFLOW_PAGE_USABLE;
int fragments = 1;
int valuePerFragment = kv.value.size();
// Figure out if we would benefit from fragmenting this kv pair. The key size must be less than
// primary page usable size, and the value and key size together must exceeed the primary page usable size.
if( (kv.key.size() + kv.value.size()) > primaryPageUsable
&& kv.key.size() < primaryPageUsable) {
// Just the part of the value that would be in a partially-filled overflow page
int overflowPartialBytes = (kv.expectedSize() - primaryPageUsable) % overflowPageUsable;
// Number of bytes wasted in the unfragmented case
int unfragmentedWaste = overflowPageUsable - overflowPartialBytes;
// Total space used for unfragmented form
int unfragmentedTotal = kv.expectedSize() + unfragmentedWaste;
// Value bytes that can fit in the primary page for each fragment
int primaryPageValueBytes = primaryPageUsable - kv.key.size();
// Calculate how many total fragments it would take to spread the partial overflow page bytes and the first fragment's primary
// page value bytes evenly over multiple tuples that fit in primary pages.
fragments = (primaryPageValueBytes + overflowPartialBytes + primaryPageValueBytes - 1) / primaryPageValueBytes;
// Number of bytes wasted in the fragmented case (for the extra key copies)
int fragmentedWaste = kv.key.size() * (fragments - 1);
// Total bytes used for the fragmented case
//int fragmentedTotal = kv.expectedSize() + fragmentedWaste;
// Calculate bytes saved by having extra key instances stored vs the original partial overflow page bytes.
int savings = unfragmentedWaste - fragmentedWaste;
double reduction = (double)savings / unfragmentedTotal;
//printf("K: %5d V: %6d OVERFLOW: %5d FRAGMENTS: %3d SAVINGS: %4d FRAG: %7d UNFRAG: %7d REDUCTION: %.3f\n",
//kv.key.size(), kv.value.size(), overflowPartialBytes, fragments, savings, fragmentedTotal, unfragmentedTotal, reduction);
if(reduction < SERVER_KNOBS->SQLITE_FRAGMENT_MIN_SAVINGS)
fragments = 1;
else
valuePerFragment = (primaryPageValueBytes + overflowPartialBytes + fragments - 1) / fragments;
}
if(fragments == 1) {
insertFragment(kv, 0, seekResult);
return;
}
// First index is ceiling(value_size / KV_FRAGMENT_INDEX_SIZE_HINT_FACTOR)
uint32_t nextIndex = (kv.value.size() + KV_FRAGMENT_INDEX_SIZE_HINT_FACTOR - 1) / KV_FRAGMENT_INDEX_SIZE_HINT_FACTOR;
// Last index is ceiling(value_size / (KV_FRAGMENT_INDEX_SIZE_HINT_FACTOR / 2) )
uint32_t finalIndex = (kv.value.size() + (KV_FRAGMENT_INDEX_SIZE_HINT_FACTOR / 2) - 1) / (KV_FRAGMENT_INDEX_SIZE_HINT_FACTOR / 2);
int bytesLeft = kv.value.size();
int readPos = 0;
while(bytesLeft > 0) {
--fragments; // remaining ideal fragment count
int fragSize = (fragments == 0) ? bytesLeft : std::min<int>(bytesLeft, valuePerFragment);
// The last fragment must have an index of finalIndex or higher.
if(fragSize == bytesLeft && nextIndex < finalIndex)
nextIndex = finalIndex;
//printf("insert ks %d vs %d fragment %d, %dbytes\n", kv.key.size(), kv.value.size(), nextIndex, fragSize);
insertFragment(KeyValueRef(kv.key, kv.value.substr(readPos, fragSize)), nextIndex, seekResult);
// seekResult can only be used for the first insertion.
if(seekResult != 0)
seekResult = 0;
readPos += fragSize;
bytesLeft -= fragSize;
++nextIndex;
}
}
else {
int r = moveTo( kv.key );
if (!r) remove();
Value v = encode(kv);
db.checkError("BTreeInsert", sqlite3BtreeInsert(cursor, v.begin(), v.size(), NULL, 0, 0, 0, r));
}
}
void clearOne( KeyRangeRef keys ) {
ASSERT(!db.fragment_values);
int r = moveTo( keys.begin );
if (r < 0) moveNext();
ASSERT( valid && decodeKV(getEncodedRow()).key < keys.end );
remove();
}
void clear( KeyRangeRef keys ) {
// TODO: This is really slow!
while (true) {
int r = moveTo( keys.begin );
if (r < 0) moveNext();
if (!valid || (db.fragment_values ? decodeKVFragment(getEncodedRow()).get().key : decodeKV(getEncodedRow()).key) >= keys.end)
break;
remove();
}
}
void fastClear( KeyRangeRef keys, bool& freeTableEmpty ) {
vector<int> clearBuffer( SERVER_KNOBS->CLEAR_BUFFER_SIZE );
clearBuffer[0] = 0;
while (true) {
if (moveTo( keys.begin )<0) moveNext();
RawCursor endCursor(db, db.table, false);
if (endCursor.moveTo( keys.end )>=0) endCursor.movePrevious();
if (!valid || !endCursor
|| (db.fragment_values ? (decodeKVFragment(getEncodedRow()).get().key >= decodeKVFragment(endCursor.getEncodedRow()).get().key)
: (decodeKV(getEncodedRow()).key > decodeKV(endCursor.getEncodedRow()).key)
)
)
break; // If empty stop!
int rc = sqlite3BtreeDeleteRange(cursor, endCursor.cursor, &clearBuffer[0], &clearBuffer[0]+clearBuffer.size());
if (rc == 201) continue;
if (!rc) break;
db.checkError("BtreeDeleteRange", rc);
}
if (clearBuffer[0]) {
//printf("fastClear(%s,%s): %d pages freed\n", printable(keys.begin).c_str(), printable(keys.end).c_str(), clearBuffer[0]);
IntKeyCursor fc(db, db.freetable, true);
int pagesDeleted = 0;
db.checkError( "BtreeLazyDelete", sqlite3BtreeLazyDelete( fc.cursor, &clearBuffer[0], &clearBuffer[0]+clearBuffer.size(), 0, &pagesDeleted ) );
ASSERT(pagesDeleted == 0);
freeTableEmpty = false;
}
}
int lazyDelete( int desiredPages ) {
vector<int> clearBuffer( SERVER_KNOBS->CLEAR_BUFFER_SIZE );
clearBuffer[0] = 0;
IntKeyCursor fc(db, db.freetable, true);
int pagesDeleted = 0;
db.checkError( "BtreeLazyDelete", sqlite3BtreeLazyDelete( fc.cursor, &clearBuffer[0], &clearBuffer[0]+clearBuffer.size(), desiredPages, &pagesDeleted ));
return pagesDeleted;
}
// Reads and reconstitutes kv fragments given cursor, an arena to allocate in, and a direction to move the cursor.
// getNext() returns the next KV pair, if there is one
// peek() returns the next key that would be read by getNext(), if there is one
// Both methods return Optionals.
// Once either method returns a non-present value, using the DefragmentingReader again is undefined behavior.
struct DefragmentingReader {
// Use this constructor for forward/backward range reads
DefragmentingReader(RawCursor &cur, Arena &m, bool forward) : cur(cur), arena(m), forward(forward), fragmentReadLimit(-1) {
parse();
}
// Use this constructor to read a SINGLE partial value from the current cursor position for an expected key.
// This exists to support IKeyValueStore::getPrefix().
// The reader will return exactly one KV pair if its key matches expectedKey, otherwise no KV pairs.
DefragmentingReader(RawCursor &cur, Arena &m, KeyRef expectedKey, int maxValueLen): cur(cur), arena(m), forward(true), maxValueLen(maxValueLen) {
fragmentReadLimit = getEncodedKVFragmentSize(expectedKey.size(), maxValueLen);
parse();
// If a key was found but it wasn't the expected key then
// clear the current kv pair and invalidate the cursor.
if(kv.present() && kv.get().key != expectedKey) {
kv = Optional<KeyValueRef>();
cur.valid = false;
}
}
private:
Optional<KeyValueRef> kv; // key and latest value fragment read
uint32_t index; // index of latest value fragment read
RawCursor &cur; // Cursor to read from
Arena &arena; // Arena to allocate key and value bytes in
bool forward; // true for forward iteration, false for reverse
int maxValueLen; // truncated value length to return
int fragmentReadLimit; // If >= 0, only read and *attempt* to decode this many fragment bytes
// Update kv with whatever is at the current cursor position if the position is valid.
void parse() {
if(cur.valid) {
// The read is either not partial or it is but the fragment read limit is at least 4 (the size of a minimal header).
bool partial = fragmentReadLimit >= 0;
ASSERT(!partial || fragmentReadLimit >= 4);
// Read full or part of fragment
ValueRef encoded = (partial) ? cur.getEncodedRowPrefix(arena, fragmentReadLimit) : cur.getEncodedRow(arena);
kv = decodeKVFragment(encoded, &index, partial);
// If this was a partial fragment then if successful update the next fragment read size, and if not
// then invalidate the cursor.
if(partial) {
if(kv.present())
fragmentReadLimit -= kv.get().value.size();
else
cur.valid = false;
}
}
else
kv = Optional<KeyValueRef>();
}
// advance cursor, parse and return key if valid
Optional<KeyRef> advance() {
if(cur.valid) {
forward ? cur.moveNext() : cur.movePrevious();
parse();
}
return kv.present() ? kv.get().key : Optional<KeyRef>();
}
public:
// Get the next key that would be returned by getNext(), if there is one
// This is more efficient than getNext() if the caller is not sure if it wants the next KV pair
Optional<KeyRef> peek() {
if(kv.present())
return kv.get().key;
return advance();
}
Optional<KeyValueRef> getNext() {
if(!peek().present())
return Optional<KeyValueRef>();
bool partial = fragmentReadLimit >= 0;
// Start out with the next KV fragment as the pair to return
KeyValueRef resultKV = kv.get();
// If index is 0 then this is an unfragmented key. It is unnecessary to advance the cursor so
// we won't, but we will clear kv so that the next peek/getNext will have to advance.
if(index == 0)
kv = Optional<KeyValueRef>();
else {
// First and last indexes in fragment group are size hints.
// First index is ceil(total_value_size / 4)
// Last index is ceil(total_value_size / 2)
// Set size depending on which of these will be first encountered and allocate buffer in arena.
// Note that if these index hints are wrong (such as if the index scheme changes) then asserts
// below will fail. They will have to be changed to expand the buffer as needed.
int size = forward ? (index * KV_FRAGMENT_INDEX_SIZE_HINT_FACTOR) : (index * (KV_FRAGMENT_INDEX_SIZE_HINT_FACTOR / 2));
uint8_t *buf = new (arena) uint8_t[size];
uint8_t *bufEnd = buf + size;
// For forward iteration wptr is the place to write to next, for reverse it's where the last write started.
uint8_t *wptr = forward ? buf : bufEnd;
int fragments = 0;
do {
++fragments;
const ValueRef &val = kv.get().value;
if(forward) {
uint8_t *w = wptr;
wptr += val.size();
ASSERT(wptr <= bufEnd);
memcpy(w, val.begin(), val.size());
// If this is a partial value get and we have enough bytes we can stop since we are forward iterating.
if(partial && wptr - buf >= maxValueLen) {
resultKV.value = ValueRef(buf, maxValueLen);
// To make further calls to peek() or getNext() return nothing, reset kv and invalidate cursor
kv = Optional<KeyValueRef>();
cur.valid = false;
return resultKV;
}
}
else {
wptr -= val.size();
ASSERT(wptr >= buf);
memcpy(wptr, val.begin(), val.size());
}
} while(advance().present() && kv.get().key == resultKV.key);
// If there was only 1 fragment, it should have been index 0 and handled above,
ASSERT(fragments != 1);
// Set final value based on direction of buffer fill
resultKV.value = forward ? ValueRef(buf, wptr - buf) : ValueRef(wptr, bufEnd - wptr);
}
// In partial value mode, we could end up here if there was only 1 fragments or maxValueLen
// was greater than the total unfragmented value size.
if(partial)
resultKV.value = resultKV.value.substr(0, std::min(resultKV.value.size(), maxValueLen));
return resultKV;
}
};
Optional<Value> get( KeyRef key ) {
int r = moveTo(key);
if(db.fragment_values) {
// Optimization - moveTo seeks to fragment (key, 0) so if it was exactly found then we
// know we have a single fragment for key and can return it.
if(r == 0) {
Value result;
((ValueRef&)result) = decodeKVFragment(getEncodedRow(result.arena())).get().value;
return result;
}
// Otherwise see if the fragments immediately after (key, 0) are for the key we want.
if(r < 0)
moveNext();
Arena m;
DefragmentingReader i(*this, m, true);
if(i.peek() == key) {
Optional<KeyValueRef> kv = i.getNext();
return Value(kv.get().value, m);
}
}
else if (r == 0) {
Value result;
KeyValueRef kv = decodeKV( getEncodedRow( result.arena() ) );
((ValueRef&)result) = kv.value;
return result;
}
return Optional<Value>();
}
Optional<Value> getPrefix( KeyRef key, int maxLength ) {
if(db.fragment_values) {
int r = moveTo(key);
if (r < 0)
moveNext();
Arena m;
DefragmentingReader i(*this, m, getEncodedKVFragmentSize(key.size(), maxLength));
if(i.peek() == key) {
Optional<KeyValueRef> kv = i.getNext();
return Value(kv.get().value, m);
}
}
else if (!moveTo(key)) {
if(maxLength == 0) {
return Value();
}
Value result;
int maxEncodedSize = getEncodedSize( key.size(), maxLength );
KeyValueRef kv = decodeKVPrefix( getEncodedRowPrefix( result.arena(), maxEncodedSize ), maxLength );
((ValueRef&)result) = kv.value;
return result;
}
return Optional<Value>();
}
Standalone<VectorRef<KeyValueRef>> getRange( KeyRangeRef keys, int rowLimit, int byteLimit ) {
Standalone<VectorRef<KeyValueRef>> result;
int accumulatedBytes = 0;
ASSERT( byteLimit > 0 );
if(db.fragment_values) {
if(rowLimit >= 0) {
int r = moveTo(keys.begin);
if (r < 0)
moveNext();
DefragmentingReader i(*this, result.arena(), true);
Optional<KeyRef> nextKey = i.peek();
while(nextKey.present() && nextKey.get() < keys.end && rowLimit-- && accumulatedBytes < byteLimit) {
Optional<KeyValueRef> kv = i.getNext();
result.push_back(result.arena(), kv.get());
accumulatedBytes += sizeof(KeyValueRef) + kv.get().expectedSize();
nextKey = i.peek();
}
}
else {
int r = moveTo(keys.end);
if (r >= 0)
movePrevious();
DefragmentingReader i(*this, result.arena(), false);
Optional<KeyRef> nextKey = i.peek();
while(nextKey.present() && nextKey.get() >= keys.begin && rowLimit++ && accumulatedBytes < byteLimit) {
Optional<KeyValueRef> kv = i.getNext();
result.push_back(result.arena(), kv.get());
accumulatedBytes += sizeof(KeyValueRef) + kv.get().expectedSize();
nextKey = i.peek();
}
}
}
else {
if (rowLimit >= 0) {
int r = moveTo( keys.begin );
if (r < 0) moveNext();
while (this->valid && rowLimit-- && accumulatedBytes < byteLimit) {
KeyValueRef kv = decodeKV( getEncodedRow( result.arena() ) );
accumulatedBytes += sizeof(KeyValueRef) + kv.expectedSize();
if (kv.key >= keys.end) break;
result.push_back( result.arena(), kv );
moveNext();
}
} else {
int r = moveTo( keys.end );
if (r >= 0) movePrevious();
while (this->valid && rowLimit++ && accumulatedBytes < byteLimit) {
KeyValueRef kv = decodeKV( getEncodedRow( result.arena() ) );
accumulatedBytes += sizeof(KeyValueRef) + kv.expectedSize();
if (kv.key < keys.begin) break;
result.push_back( result.arena(), kv );
movePrevious();
}
}
}
return result;
}
int moveTo( KeyRef key, bool ignore_fragment_mode = false ) {
UnpackedRecord r;
r.pKeyInfo = &keyInfo;
r.flags = UNPACKED_PREFIX_MATCH; // This record [key] can be considered equal to a record [key,value] for any value
Mem tupleValues[2];
r.aMem = tupleValues;
// Set field 1 of tuple to key, which is a string type with typecode 12 + 2*len
tupleValues[0].db = keyInfo.db;
tupleValues[0].enc = keyInfo.enc;
tupleValues[0].zMalloc = NULL;
ASSERT(sqlite3VdbeSerialGet(key.begin(), 12 + (2 * key.size()), &tupleValues[0]) == key.size());
// In fragmenting mode, seek is to (k, 0, ), otherwise just (k, ).
if(ignore_fragment_mode || !db.fragment_values)
r.nField = 1;
else {
// Set field 2 of tuple to the null type which is typecode 0
tupleValues[1].db = keyInfo.db;
tupleValues[1].enc = keyInfo.enc;
tupleValues[1].zMalloc = NULL;
ASSERT(sqlite3VdbeSerialGet(NULL, 0, &tupleValues[1]) == 0);
r.nField = 2;
}
int result;
db.checkError("BtreeMovetoUnpacked", sqlite3BtreeMovetoUnpacked(cursor, &r, 0, 0, &result));
valid = result >= 0 || !sqlite3BtreeEof(cursor);
return result;
}
};
struct Cursor : SQLiteTransaction, RawCursor {
Cursor( SQLiteDB& db, bool write) : SQLiteTransaction(db, write), RawCursor(db, db.table, write) {
}
};
struct ReadCursor : ReferenceCounted<ReadCursor>, FastAllocated<ReadCursor> {
// Readers need to be reset (forced to move to a new snapshot) when the writer thread does a checkpoint.
// ReadCursor is reference counted so that the writer can clear the persistent reference (readCursors[n]) and
// readers can hold an additional reference when they actually have a read happening.
// ReadCursor lazily constructs its actual Cursor (and hence transaction) because it's vital that readCursors[n] be
// assigned before the transaction is opened.
ReadCursor() : valid(false) {}
void init(SQLiteDB& db) { new (&cursor) Cursor(db, false); valid = true; }
~ReadCursor() { if (valid) get().~Cursor(); }
Cursor& get() { return *((Cursor*)&cursor); }
private:
std::aligned_storage< sizeof(Cursor), __alignof(Cursor) >::type cursor;
bool valid;
};
extern bool vfsAsyncIsOpen( std::string filename );
// Returns number of pages which failed checksum.
int SQLiteDB::checkAllPageChecksums() {
ASSERT( !haveMutex );
ASSERT( page_checksums ); // This should never be called on SQLite databases that do not have page checksums.
double startT = timer();
// First try to open an existing file
std::string apath = abspath(filename);
std::string walpath = apath + "-wal";
/* REMOVE THIS BEFORE CHECKIN */ if(!fileExists(apath)) return 0;
TraceEvent("SQLitePageChecksumScanBegin").detail("File", apath);
ErrorOr<Reference<IAsyncFile>> dbFile = waitForAndGet( errorOr( IAsyncFileSystem::filesystem()->open( apath, IAsyncFile::OPEN_READONLY | IAsyncFile::OPEN_LOCK, 0 ) ) );
ErrorOr<Reference<IAsyncFile>> walFile = waitForAndGet( errorOr( IAsyncFileSystem::filesystem()->open( walpath, IAsyncFile::OPEN_READONLY | IAsyncFile::OPEN_LOCK, 0 ) ) );
if (dbFile.isError()) throw dbFile.getError(); // If we've failed to open the file, throw an exception
if (walFile.isError()) throw walFile.getError(); // If we've failed to open the file, throw an exception
// Now that the file itself is open and locked, let sqlite open the database
// Note that VFSAsync will also call g_network->open (including for the WAL), so its flags are important, too
// TODO: If better performance is needed, make AsyncFileReadAheadCache work and be enabled by SQLITE_OPEN_READAHEAD which was added for that purpose.
int result = sqlite3_open_v2(apath.c_str(), &db, SQLITE_OPEN_READONLY, NULL);
checkError("open", result);
// This check has the useful side effect of actually opening/reading the database. If we were not doing this,
// then we could instead open a read cursor for the same effect, as currently tryReadEveryDbPage() requires it.
Statement *jm = new Statement(*this, "PRAGMA journal_mode");
ASSERT( jm->nextRow() );
if (jm->column(0) != LiteralStringRef("wal")){
TraceEvent(SevError, "JournalModeError").detail("Filename", filename).detail("Mode", jm->column(0));
ASSERT( false );
}
delete jm;
btree = db->aDb[0].pBt;
initPagerCodec();
sqlite3_extended_result_codes(db, 1);
sqlite3_mutex_enter(db->mutex);
haveMutex = true;
pPagerCodec->silent = true;
Pgno p = 1;
int readErrors = 0;
int corruptPages = 0;
int totalErrors = 0;
while(1) {
int type;
int zero;
int rc = tryReadEveryDbPage(db, p, &p, &type, &zero);
if(rc == SQLITE_OK)
break;
if(rc == SQLITE_CORRUPT) {
TraceEvent(SevWarnAlways, "SQLitePageChecksumScanCorruptPage")
.detail("File", filename)
.detail("PageNumber", p)
.detail("PageType", type)
.detail("PageWasZeroed", zero);
++corruptPages;
} else {
TraceEvent(SevWarnAlways, "SQLitePageChecksumScanReadFailed")
.detail("File", filename)
.detail("PageNumber", p)
.detail("SQLiteError", sqlite3ErrStr(rc))
.detail("SQLiteErrorCode", rc);
++readErrors;
}
++p;
if(++totalErrors >= SERVER_KNOBS->SQLITE_PAGE_SCAN_ERROR_LIMIT)
break;
}
pPagerCodec->silent = false;
haveMutex = false;
sqlite3_mutex_leave(db->mutex);
sqlite3_close(db);
TraceEvent("SQLitePageChecksumScanEnd")
.detail("Elapsed", DEBUG_DETERMINISM ? 0 : timer()-startT)
.detail("Filename", filename)
.detail("CorruptPages", corruptPages)
.detail("ReadErrors", readErrors)
.detail("TotalErrors", totalErrors);
ASSERT(!vfsAsyncIsOpen(filename));
return totalErrors;
}
void SQLiteDB::open(bool writable) {
ASSERT( !haveMutex );
double startT = timer();
//TraceEvent("KVThreadInitStage").detail("Stage",1).detail("Filename", filename).detail("Writable", writable);
// First try to open an existing file
std::string apath = abspath(filename);
std::string walpath = apath + "-wal";
ErrorOr<Reference<IAsyncFile>> dbFile = waitForAndGet( errorOr( IAsyncFileSystem::filesystem()->open( apath, IAsyncFile::OPEN_READWRITE | IAsyncFile::OPEN_LOCK, 0 ) ) );
ErrorOr<Reference<IAsyncFile>> walFile = waitForAndGet( errorOr( IAsyncFileSystem::filesystem()->open( walpath, IAsyncFile::OPEN_READWRITE | IAsyncFile::OPEN_LOCK, 0 ) ) );
//TraceEvent("KVThreadInitStage").detail("Stage",15).detail("Filename", apath).detail("Writable", writable).detail("IsErr", dbFile.isError());
if (writable) {
if (dbFile.isError() && dbFile.getError().code() == error_code_file_not_found && !fileExists(apath) && // db file is missing
!walFile.isError() && fileExists(walpath)) // ..but WAL file is present
{
// Either we died partway through creating this DB, or died partway through deleting it, or someone is monkeying with our files
// Create a new blank DB by backing up the WAL file (just in case it is important) and then hitting the next case
walFile = file_not_found();
renameFile( walpath, walpath + "-old-" + deterministicRandom()->randomUniqueID().toString() );
ASSERT_WE_THINK(false); //< This code should not be hit in FoundationDB at the moment, because worker looks for databases to open by listing .fdb files, not .fdb-wal files
//TEST(true); // Replace a partially constructed or destructed DB
}
if (dbFile.isError() && walFile.isError() && writable &&
dbFile.getError().code() == error_code_file_not_found &&
walFile.getError().code() == error_code_file_not_found &&
!fileExists(apath) && !fileExists(walpath))
{
// The file doesn't exist, try to create a new one
// Creating the WAL before the database ensures we will not try to open a database with no WAL
walFile = waitForAndGet( IAsyncFileSystem::filesystem()->open( walpath, IAsyncFile::OPEN_ATOMIC_WRITE_AND_CREATE | IAsyncFile::OPEN_CREATE | IAsyncFile::OPEN_READWRITE | IAsyncFile::OPEN_LOCK, 0600 ) );
waitFor( walFile.get()->sync() );
dbFile = waitForAndGet( IAsyncFileSystem::filesystem()->open( apath, IAsyncFile::OPEN_ATOMIC_WRITE_AND_CREATE | IAsyncFile::OPEN_CREATE | IAsyncFile::OPEN_READWRITE | IAsyncFile::OPEN_LOCK, 0600 ) );
if(page_checksums)
waitFor( dbFile.get()->write( template_fdb_with_page_checksums, sizeof(template_fdb_with_page_checksums), 0 ) );
else
waitFor( dbFile.get()->write( template_fdb_without_page_checksums, sizeof(template_fdb_without_page_checksums), 0 ) );
waitFor( dbFile.get()->sync() ); // renames filename.part to filename, fsyncs data and directory
TraceEvent("CreatedDBFile").detail("Filename", apath);
}
}
if (dbFile.isError()) throw dbFile.getError(); // If we've failed to open the file, throw an exception
if (walFile.isError()) throw walFile.getError(); // If we've failed to open the file, throw an exception
//TraceEvent("KVThreadInitStage").detail("Stage",2).detail("Filename", filename).detail("Writable", writable);
// Now that the file itself is open and locked, let sqlite open the database
// Note that VFSAsync will also call g_network->open (including for the WAL), so its flags are important, too
int result = sqlite3_open_v2(apath.c_str(), &db, (writable ? SQLITE_OPEN_READWRITE : SQLITE_OPEN_READONLY), NULL);
checkError("open", result);
int chunkSize;
if( !g_network->isSimulated() ) {
chunkSize = 4096 * SERVER_KNOBS->SQLITE_CHUNK_SIZE_PAGES;
} else if( BUGGIFY ) {
chunkSize = 4096 * deterministicRandom()->randomInt(0, 100);
} else {
chunkSize = 4096 * SERVER_KNOBS->SQLITE_CHUNK_SIZE_PAGES_SIM;
}
checkError("setChunkSize", sqlite3_file_control(db, nullptr, SQLITE_FCNTL_CHUNK_SIZE, &chunkSize));
btree = db->aDb[0].pBt;
initPagerCodec();
sqlite3_extended_result_codes(db, 1);
//TraceEvent("KVThreadInitStage").detail("Stage",3).detail("Filename", filename).detail("Writable", writable);
//Statement(*this, "PRAGMA cache_size = 100").execute();
Statement jm(*this, "PRAGMA journal_mode");
ASSERT( jm.nextRow() );
if (jm.column(0) != LiteralStringRef("wal")){
TraceEvent(SevError, "JournalModeError").detail("Filename", filename).detail("Mode", jm.column(0));
ASSERT( false );
}
if (writable) {
Statement(*this, "PRAGMA synchronous = NORMAL").execute(); // OFF, NORMAL, FULL
Statement(*this, "PRAGMA wal_autocheckpoint = -1").nextRow();
}
//TraceEvent("KVThreadInitStage").detail("Stage",4).detail("Filename", filename).detail("Writable", writable);
sqlite3_mutex_enter(db->mutex);
haveMutex = true;
table = 3;
freetable = 4;
this->dbFile = dbFile.get();
this->walFile = walFile.get();
TraceEvent("KVThreadInitTime").detail("Elapsed", DEBUG_DETERMINISM ? 0 : timer()-startT).detail("Filename", filename).detail("Writable", writable);
ASSERT(vfsAsyncIsOpen(filename));
}
void SQLiteDB::createFromScratch() {
int sqliteFlags = SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE;
checkError("open", sqlite3_open_v2(filename.c_str(), &db, sqliteFlags, NULL));
Statement(*this, "PRAGMA page_size = 4096").nextRow(); //fast
btree = db->aDb[0].pBt;
initPagerCodec();
Statement(*this, "PRAGMA auto_vacuum = 2").nextRow(); //slow all the time
Statement(*this, "PRAGMA journal_mode = WAL").nextRow(); // sometimes slow
sqlite3_extended_result_codes(db, 1);
sqlite3_mutex_enter(db->mutex);
haveMutex = true;
beginTransaction(true);
u32 pgnoRoot = -1;
sqlite3BtreeGetMeta(btree, BTREE_LARGEST_ROOT_PAGE, &pgnoRoot);
// We expect our tables are #3, #4 (since autovacuum is enabled, there is a pointer map page at #2)
if (pgnoRoot == 4) {
table = pgnoRoot-1;
freetable = pgnoRoot;
rollback();
} else if (pgnoRoot == 1){
// The database is empty; create tables
checkError("BtreeCreateTable", sqlite3BtreeCreateTable( btree, &table, BTREE_BLOBKEY ));
ASSERT( table == 3 );
checkError("BtreeCreateTable2", sqlite3BtreeCreateTable( btree, &freetable, BTREE_INTKEY ));
ASSERT( freetable == table+1 );
endTransaction();
} else {
TraceEvent("PgnoRoot").detail("Value", pgnoRoot);
checkError("CheckTables", SQLITE_CORRUPT);
}
}
struct ThreadSafeCounter {
volatile int64_t counter;
ThreadSafeCounter() : counter(0) {}
void operator ++() { interlockedIncrement64(&counter); }
void operator --() { interlockedDecrement64(&counter); }
operator const int64_t() const { return counter; }
};
class KeyValueStoreSQLite : public IKeyValueStore {
public:
virtual void dispose() {
doClose(this, true);
}
virtual void close() {
doClose(this, false);
}
virtual Future<Void> getError() { return delayed( readThreads->getError() || writeThread->getError() ); }
virtual Future<Void> onClosed() { return stopped.getFuture(); }
virtual KeyValueStoreType getType() { return type; }
virtual StorageBytes getStorageBytes();
virtual void set( KeyValueRef keyValue, const Arena* arena = NULL );
virtual void clear( KeyRangeRef range, const Arena* arena = NULL );
virtual Future<Void> commit(bool sequential = false);
virtual Future<Optional<Value>> readValue( KeyRef key, Optional<UID> debugID );
virtual Future<Optional<Value>> readValuePrefix( KeyRef key, int maxLength, Optional<UID> debugID );
virtual Future<Standalone<VectorRef<KeyValueRef>>> readRange( KeyRangeRef keys, int rowLimit = 1<<30, int byteLimit = 1<<30 );
KeyValueStoreSQLite(std::string const& filename, UID logID, KeyValueStoreType type, bool checkChecksums, bool checkIntegrity);
~KeyValueStoreSQLite();
struct SpringCleaningWorkPerformed {
int lazyDeletePages = 0;
int vacuumedPages = 0;
};
Future<SpringCleaningWorkPerformed> doClean();
void startReadThreads();
private:
KeyValueStoreType type;
UID logID;
std::string filename;
Reference<IThreadPool> readThreads, writeThread;
Promise<Void> stopped;
Future<Void> cleaning, logging, starting, stopOnErr;
int64_t readsRequested, writesRequested;
ThreadSafeCounter readsComplete;
volatile int64_t writesComplete;
volatile SpringCleaningStats springCleaningStats;
volatile int64_t diskBytesUsed;
volatile int64_t freeListPages;
vector< Reference<ReadCursor> > readCursors;
struct Reader : IThreadPoolReceiver {
SQLiteDB conn;
ThreadSafeCounter& counter;
UID dbgid;
Reference<ReadCursor>* ppReadCursor;
explicit Reader( std::string const& filename, bool is_btree_v2, ThreadSafeCounter& counter, UID dbgid, Reference<ReadCursor>* ppReadCursor )
: conn( filename, is_btree_v2, is_btree_v2 ), counter(counter), dbgid(dbgid), ppReadCursor(ppReadCursor)
{
}
~Reader() {
ppReadCursor->clear();
}
virtual void init() {
conn.open(false);
}
Reference<ReadCursor> getCursor() {
Reference<ReadCursor> cursor = *ppReadCursor;
if (!cursor) {
*ppReadCursor = cursor = Reference<ReadCursor>(new ReadCursor);
cursor->init(conn);
}
return cursor;
}
struct ReadValueAction : TypedAction<Reader, ReadValueAction>, FastAllocated<ReadValueAction> {
Key key;
Optional<UID> debugID;
ThreadReturnPromise<Optional<Value>> result;
ReadValueAction(Key key, Optional<UID> debugID) : key(key), debugID(debugID) {};
virtual double getTimeEstimate() { return SERVER_KNOBS->READ_VALUE_TIME_ESTIMATE; }
};
void action( ReadValueAction& rv ) {
//double t = timer();
if (rv.debugID.present()) g_traceBatch.addEvent("GetValueDebug", rv.debugID.get().first(), "Reader.Before"); //.detail("TaskID", g_network->getCurrentTask());
rv.result.send( getCursor()->get().get(rv.key) );
++counter;
if (rv.debugID.present()) g_traceBatch.addEvent("GetValueDebug", rv.debugID.get().first(), "Reader.After"); //.detail("TaskID", g_network->getCurrentTask());
//t = timer()-t;
//if (t >= 1.0) TraceEvent("ReadValueActionSlow",dbgid).detail("Elapsed", t);
}
struct ReadValuePrefixAction : TypedAction<Reader, ReadValuePrefixAction>, FastAllocated<ReadValuePrefixAction> {
Key key;
int maxLength;
Optional<UID> debugID;
ThreadReturnPromise<Optional<Value>> result;
ReadValuePrefixAction(Key key, int maxLength, Optional<UID> debugID) : key(key), maxLength(maxLength), debugID(debugID) {};
virtual double getTimeEstimate() { return SERVER_KNOBS->READ_VALUE_TIME_ESTIMATE; }
};
void action( ReadValuePrefixAction& rv ) {
//double t = timer();
if (rv.debugID.present()) g_traceBatch.addEvent("GetValuePrefixDebug", rv.debugID.get().first(), "Reader.Before"); //.detail("TaskID", g_network->getCurrentTask());
rv.result.send( getCursor()->get().getPrefix(rv.key, rv.maxLength) );
++counter;
if (rv.debugID.present()) g_traceBatch.addEvent("GetValuePrefixDebug", rv.debugID.get().first(), "Reader.After"); //.detail("TaskID", g_network->getCurrentTask());
//t = timer()-t;
//if (t >= 1.0) TraceEvent("ReadValuePrefixActionSlow",dbgid).detail("Elapsed", t);
}
struct ReadRangeAction : TypedAction<Reader, ReadRangeAction>, FastAllocated<ReadRangeAction> {
KeyRange keys;
int rowLimit, byteLimit;
ThreadReturnPromise<Standalone<VectorRef<KeyValueRef>>> result;
ReadRangeAction(KeyRange keys, int rowLimit, int byteLimit) : keys(keys), rowLimit(rowLimit), byteLimit(byteLimit) {}
virtual double getTimeEstimate() { return SERVER_KNOBS->READ_RANGE_TIME_ESTIMATE; }
};
void action( ReadRangeAction& rr ) {
rr.result.send( getCursor()->get().getRange(rr.keys, rr.rowLimit, rr.byteLimit) );
++counter;
}
};
struct Writer : IThreadPoolReceiver {
SQLiteDB conn;
Cursor* cursor;
int commits;
int setsThisCommit;
bool freeTableEmpty; // true if we are sure the freetable (pages pending lazy deletion) is empty
volatile int64_t& writesComplete;
volatile SpringCleaningStats& springCleaningStats;
volatile int64_t& diskBytesUsed;
volatile int64_t& freeListPages;
UID dbgid;
vector<Reference<ReadCursor>>& readThreads;
bool checkAllChecksumsOnOpen;
bool checkIntegrityOnOpen;
explicit Writer( std::string const& filename, bool isBtreeV2, bool checkAllChecksumsOnOpen, bool checkIntegrityOnOpen, volatile int64_t& writesComplete, volatile SpringCleaningStats& springCleaningStats, volatile int64_t& diskBytesUsed, volatile int64_t& freeListPages, UID dbgid, vector<Reference<ReadCursor>>* pReadThreads )
: conn( filename, isBtreeV2, isBtreeV2 ),
commits(), setsThisCommit(),
freeTableEmpty(false),
writesComplete(writesComplete),
springCleaningStats(springCleaningStats),
diskBytesUsed(diskBytesUsed),
freeListPages(freeListPages),
cursor(NULL),
dbgid(dbgid),
readThreads(*pReadThreads),
checkAllChecksumsOnOpen(checkAllChecksumsOnOpen),
checkIntegrityOnOpen(checkIntegrityOnOpen)
{
}
~Writer() {
TraceEvent("KVWriterDestroying", dbgid);
delete cursor;
TraceEvent("KVWriterDestroyed", dbgid);
}
virtual void init() {
if(checkAllChecksumsOnOpen) {
if(conn.checkAllPageChecksums() != 0) {
// It's not strictly necessary to discard the file immediately if a page checksum error is found
// because most of the file could be valid and bad pages will be detected if they are read.
// However, we shouldn't use the file unless we absolutely have to because some range(s) of keys
// have effectively lost a replica.
throw file_corrupt();
}
}
conn.open(true);
//If a wal file fails during the commit process before finishing a checkpoint, then it is possible that our wal file will be non-empty
//when we reload it. We execute a checkpoint here to remedy that situation. This call must come before before creating a cursor because
//it will fail if there are any outstanding transactions.
fullCheckpoint();
cursor = new Cursor(conn, true);
if (checkIntegrityOnOpen || EXPENSIVE_VALIDATION) {
if(conn.check(false) != 0) {
// A corrupt btree structure must not be used.
if (g_network->isSimulated() && (g_simulator.getCurrentProcess()->fault_injection_p1 || g_simulator.getCurrentProcess()->machine->machineProcess->fault_injection_p1 || g_simulator.getCurrentProcess()->rebooting)) {
throw file_corrupt().asInjectedFault();
} else {
throw file_corrupt();
}
}
}
}
struct InitAction : TypedAction<Writer, InitAction>, FastAllocated<InitAction> {
ThreadReturnPromise<Void> result;
virtual double getTimeEstimate() { return 0; }
};
void action(InitAction& a) {
// init() has already been called
a.result.send(Void());
}
struct SetAction : TypedAction<Writer, SetAction>, FastAllocated<SetAction> {
KeyValue kv;
SetAction( KeyValue kv ) : kv(kv) {}
virtual double getTimeEstimate() { return SERVER_KNOBS->SET_TIME_ESTIMATE; }
};
void action(SetAction& a) {
double s = now();
checkFreePages();
cursor->set(a.kv);
++setsThisCommit;
++writesComplete;
if (g_network->isSimulated() && g_simulator.getCurrentProcess()->rebooting)
TraceEvent("SetActionFinished", dbgid).detail("Elapsed", now()-s);
}
struct ClearAction : TypedAction<Writer, ClearAction>, FastAllocated<ClearAction> {
KeyRange range;
ClearAction( KeyRange range ) : range(range) {}
virtual double getTimeEstimate() { return SERVER_KNOBS->CLEAR_TIME_ESTIMATE; }
};
void action(ClearAction& a) {
double s = now();
cursor->fastClear(a.range, freeTableEmpty);
cursor->clear(a.range); // TODO: at most one
++writesComplete;
if (g_network->isSimulated() && g_simulator.getCurrentProcess()->rebooting)
TraceEvent("ClearActionFinished", dbgid).detail("Elapsed", now()-s);
}
struct CommitAction : TypedAction<Writer, CommitAction>, FastAllocated<CommitAction> {
double issuedTime;
ThreadReturnPromise<Void> result;
CommitAction() : issuedTime(now()) {}
virtual double getTimeEstimate() { return SERVER_KNOBS->COMMIT_TIME_ESTIMATE; }
};
void action(CommitAction& a) {
double t1 = now();
cursor->commit();
delete cursor;
cursor = NULL;
double t2 = now();
fullCheckpoint();
double t3 = now();
++commits;
//if ( !(commits % 100) )
//printf("dbf=%lld bytes, wal=%lld bytes\n", getFileSize((kv->filename+".fdb").c_str()), getFileSize((kv->filename+".fdb-wal").c_str()));
a.result.send(Void());
cursor = new Cursor(conn, true);
checkFreePages();
++writesComplete;
if (t3-a.issuedTime > 10.0*deterministicRandom()->random01())
TraceEvent("KVCommit10sSample", dbgid).detail("Queued", t1-a.issuedTime).detail("Commit", t2-t1).detail("Checkpoint", t3-t2);
diskBytesUsed = waitForAndGet( conn.dbFile->size() ) + waitForAndGet( conn.walFile->size() );
if (g_network->isSimulated() && g_simulator.getCurrentProcess()->rebooting)
TraceEvent("CommitActionFinished", dbgid).detail("Elapsed", now()-t1);
}
//Checkpoints the database and resets the wal file back to the beginning
void fullCheckpoint() {
//A checkpoint cannot succeed while there is an outstanding transaction
ASSERT(cursor == NULL);
resetReaders();
conn.checkpoint(false);
resetReaders();
conn.checkpoint(true);
}
void resetReaders() {
for(int i=0; i<readThreads.size(); i++)
readThreads[i].clear();
}
void checkFreePages() {
int iterations = 0;
int64_t freeListSize = freeListPages;
while (!freeTableEmpty && freeListSize < SERVER_KNOBS->CHECK_FREE_PAGE_AMOUNT) {
int deletedPages = cursor->lazyDelete(SERVER_KNOBS->CHECK_FREE_PAGE_AMOUNT);
freeTableEmpty = (deletedPages != SERVER_KNOBS->CHECK_FREE_PAGE_AMOUNT);
springCleaningStats.lazyDeletePages += deletedPages;
++iterations;
freeListSize = conn.freePages();
}
freeListPages = freeListSize;
//if (iterations) printf("Lazy free: %d pages on freelist, %d iterations, freeTableEmpty=%d\n", freeListPages, iterationsi, freeTableEmpty);
}
struct SpringCleaningAction : TypedAction<Writer, SpringCleaningAction>, FastAllocated<SpringCleaningAction> {
ThreadReturnPromise<SpringCleaningWorkPerformed> result;
virtual double getTimeEstimate() {
return std::max(SERVER_KNOBS->SPRING_CLEANING_LAZY_DELETE_TIME_ESTIMATE, SERVER_KNOBS->SPRING_CLEANING_VACUUM_TIME_ESTIMATE);
}
};
void action(SpringCleaningAction& a) {
double s = now();
double lazyDeleteEnd = now() + SERVER_KNOBS->SPRING_CLEANING_LAZY_DELETE_TIME_ESTIMATE;
double vacuumEnd = now() + SERVER_KNOBS->SPRING_CLEANING_VACUUM_TIME_ESTIMATE;
SpringCleaningWorkPerformed workPerformed;
double lazyDeleteTime = 0;
double vacuumTime = 0;
const double lazyDeleteBatchProbability = 1.0 / (1 + SERVER_KNOBS->SPRING_CLEANING_VACUUMS_PER_LAZY_DELETE_PAGE * std::max(1, SERVER_KNOBS->SPRING_CLEANING_LAZY_DELETE_BATCH_SIZE));
bool vacuumFinished = false;
loop {
double begin = now();
bool canDelete = !freeTableEmpty
&& (now() < lazyDeleteEnd || workPerformed.lazyDeletePages < SERVER_KNOBS->SPRING_CLEANING_MIN_LAZY_DELETE_PAGES)
&& workPerformed.lazyDeletePages < SERVER_KNOBS->SPRING_CLEANING_MAX_LAZY_DELETE_PAGES;
bool canVacuum = !vacuumFinished
&& (now() < vacuumEnd || workPerformed.vacuumedPages < SERVER_KNOBS->SPRING_CLEANING_MIN_VACUUM_PAGES)
&& workPerformed.vacuumedPages < SERVER_KNOBS->SPRING_CLEANING_MAX_VACUUM_PAGES;
if(!canDelete && !canVacuum) {
break;
}
if(canDelete && (!canVacuum || deterministicRandom()->random01() < lazyDeleteBatchProbability)) {
TEST(canVacuum); // SQLite lazy deletion when vacuuming is active
TEST(!canVacuum); // SQLite lazy deletion when vacuuming is inactive
int pagesToDelete = std::max(1, std::min(SERVER_KNOBS->SPRING_CLEANING_LAZY_DELETE_BATCH_SIZE, SERVER_KNOBS->SPRING_CLEANING_MAX_LAZY_DELETE_PAGES - workPerformed.lazyDeletePages));
int pagesDeleted = cursor->lazyDelete(pagesToDelete) ;
freeTableEmpty = (pagesDeleted != pagesToDelete);
workPerformed.lazyDeletePages += pagesDeleted;
lazyDeleteTime += now() - begin;
}
else {
ASSERT(canVacuum);
TEST(canDelete); // SQLite vacuuming when lazy delete is active
TEST(!canDelete); // SQLite vacuuming when lazy delete is inactive
TEST(SERVER_KNOBS->SPRING_CLEANING_VACUUMS_PER_LAZY_DELETE_PAGE != 0); //SQLite vacuuming with nonzero vacuums_per_lazy_delete_page
vacuumFinished = conn.vacuum();
if(!vacuumFinished) {
++workPerformed.vacuumedPages;
}
vacuumTime += now() - begin;
}
CoroThreadPool::waitFor(yield());
}
freeListPages = conn.freePages();
TEST(workPerformed.lazyDeletePages > 0); // Pages lazily deleted
TEST(workPerformed.vacuumedPages > 0); // Pages vacuumed
TEST(vacuumTime > 0); // Time spent vacuuming
TEST(lazyDeleteTime > 0); // Time spent lazy deleting
++springCleaningStats.springCleaningCount;
springCleaningStats.lazyDeletePages += workPerformed.lazyDeletePages;
springCleaningStats.vacuumedPages += workPerformed.vacuumedPages;
springCleaningStats.springCleaningTime += now() - s;
springCleaningStats.vacuumTime += vacuumTime;
springCleaningStats.lazyDeleteTime += lazyDeleteTime;
a.result.send(workPerformed);
++writesComplete;
if (g_network->isSimulated() && g_simulator.getCurrentProcess()->rebooting)
TraceEvent("SpringCleaningActionFinished", dbgid).detail("Elapsed", now()-s);
}
};
ACTOR static Future<Void> logPeriodically( KeyValueStoreSQLite* self ) {
state int64_t lastReadsComplete = 0;
state int64_t lastWritesComplete = 0;
loop {
wait( delay(SERVER_KNOBS->DISK_METRIC_LOGGING_INTERVAL) );
int64_t rc = self->readsComplete, wc = self->writesComplete;
TraceEvent("DiskMetrics", self->logID)
.detail("ReadOps", rc - lastReadsComplete)
.detail("WriteOps", wc - lastWritesComplete)
.detail("ReadQueue", self->readsRequested - rc)
.detail("WriteQueue", self->writesRequested - wc)
.detail("GlobalSQLiteMemoryHighWater", (int64_t)sqlite3_memory_highwater(1));
TraceEvent("SpringCleaningMetrics", self->logID)
.detail("SpringCleaningCount", self->springCleaningStats.springCleaningCount)
.detail("LazyDeletePages", self->springCleaningStats.lazyDeletePages)
.detail("VacuumedPages", self->springCleaningStats.vacuumedPages)
.detail("SpringCleaningTime", self->springCleaningStats.springCleaningTime)
.detail("LazyDeleteTime", self->springCleaningStats.lazyDeleteTime)
.detail("VacuumTime", self->springCleaningStats.vacuumTime);
lastReadsComplete = self->readsComplete;
lastWritesComplete = self->writesComplete;
}
}
ACTOR static Future<Void> stopOnError( KeyValueStoreSQLite* self ) {
try {
wait( self->readThreads->getError() || self->writeThread->getError() );
} catch (Error& e) {
if (e.code() == error_code_actor_cancelled)
throw;
}
self->readThreads->stop();
self->writeThread->stop();
return Void();
}
ACTOR static void doClose( KeyValueStoreSQLite* self, bool deleteOnClose ) {
state Error error = success();
try {
TraceEvent("KVClose", self->logID).detail("Del", deleteOnClose);
self->starting.cancel();
self->cleaning.cancel();
self->logging.cancel();
wait( self->readThreads->stop() && self->writeThread->stop() );
if (deleteOnClose) {
wait( IAsyncFileSystem::filesystem()->incrementalDeleteFile( self->filename, true ) );
wait( IAsyncFileSystem::filesystem()->incrementalDeleteFile( self->filename + "-wal", false ) );
}
} catch (Error& e) {
TraceEvent(SevError, "KVDoCloseError", self->logID)
.error(e,true)
.detail("Reason", e.code() == error_code_platform_error ? "could not delete database" : "unknown");
error = e;
}
TraceEvent("KVClosed", self->logID);
if( error.code() != error_code_actor_cancelled ) {
self->stopped.send(Void());
delete self;
}
}
};
IKeyValueStore* keyValueStoreSQLite( std::string const& filename, UID logID, KeyValueStoreType storeType, bool checkChecksums, bool checkIntegrity) {
return new KeyValueStoreSQLite(filename, logID, storeType, checkChecksums, checkIntegrity);
}
ACTOR Future<Void> cleanPeriodically( KeyValueStoreSQLite* self ) {
wait(delayJittered(SERVER_KNOBS->SPRING_CLEANING_NO_ACTION_INTERVAL));
loop {
KeyValueStoreSQLite::SpringCleaningWorkPerformed workPerformed = wait(self->doClean());
double duration = std::numeric_limits<double>::max();
if (workPerformed.lazyDeletePages >= SERVER_KNOBS->SPRING_CLEANING_LAZY_DELETE_BATCH_SIZE) {
duration = std::min(duration, SERVER_KNOBS->SPRING_CLEANING_LAZY_DELETE_INTERVAL);
}
if (workPerformed.vacuumedPages > 0) {
duration = std::min(duration, SERVER_KNOBS->SPRING_CLEANING_VACUUM_INTERVAL);
}
if (duration == std::numeric_limits<double>::max()) {
duration = SERVER_KNOBS->SPRING_CLEANING_NO_ACTION_INTERVAL;
}
wait(delayJittered(duration));
}
}
ACTOR static Future<Void> startReadThreadsWhen( KeyValueStoreSQLite* kv, Future<Void> onReady, UID id ) {
wait(onReady);
kv->startReadThreads();
return Void();
}
sqlite3_vfs *vfsAsync();
static int vfs_registered = 0;
KeyValueStoreSQLite::KeyValueStoreSQLite(std::string const& filename, UID id, KeyValueStoreType storeType, bool checkChecksums, bool checkIntegrity)
: type(storeType),
filename(filename),
logID(id),
readThreads(CoroThreadPool::createThreadPool()),
writeThread(CoroThreadPool::createThreadPool()),
readsRequested(0), writesRequested(0), writesComplete(0), diskBytesUsed(0), freeListPages(0)
{
stopOnErr = stopOnError(this);
#if SQLITE_THREADSAFE == 0
ASSERT( writeThread->isCoro() );
#endif
if (!vfs_registered && writeThread->isCoro())
if (sqlite3_vfs_register( vfsAsync(), true ) != SQLITE_OK)
ASSERT(false);
//The DB file should not already be open
ASSERT(!vfsAsyncIsOpen(filename));
readCursors.resize(64); //< number of read threads
sqlite3_soft_heap_limit64( SERVER_KNOBS->SOFT_HEAP_LIMIT ); // SOMEDAY: Is this a performance issue? Should we drop the cache sizes for individual threads?
TaskPriority taskId = g_network->getCurrentTask();
g_network->setCurrentTask(TaskPriority::DiskWrite);
writeThread->addThread( new Writer(filename, type==KeyValueStoreType::SSD_BTREE_V2, checkChecksums, checkIntegrity, writesComplete, springCleaningStats, diskBytesUsed, freeListPages, id, &readCursors) );
g_network->setCurrentTask(taskId);
auto p = new Writer::InitAction();
auto f = p->result.getFuture();
writeThread->post( p );
starting = startReadThreadsWhen( this, f, logID );
cleaning = cleanPeriodically(this);
logging = logPeriodically(this);
}
KeyValueStoreSQLite::~KeyValueStoreSQLite() {
//printf("dbf=%lld bytes, wal=%lld bytes\n", getFileSize((filename+".fdb").c_str()), getFileSize((filename+".fdb-wal").c_str()));
}
StorageBytes KeyValueStoreSQLite::getStorageBytes() {
int64_t free;
int64_t total;
g_network->getDiskBytes(parentDirectory(filename), free, total);
return StorageBytes(free, total, diskBytesUsed, free + _PAGE_SIZE * freeListPages);
}
void KeyValueStoreSQLite::startReadThreads() {
int nReadThreads = readCursors.size();
TaskPriority taskId = g_network->getCurrentTask();
g_network->setCurrentTask(TaskPriority::DiskRead);
for(int i=0; i<nReadThreads; i++)
readThreads->addThread( new Reader(filename, type==KeyValueStoreType::SSD_BTREE_V2, readsComplete, logID, &readCursors[i]) );
g_network->setCurrentTask(taskId);
}
void KeyValueStoreSQLite::set( KeyValueRef keyValue, const Arena* arena ) {
++writesRequested;
writeThread->post( new Writer::SetAction(keyValue) );
}
void KeyValueStoreSQLite::clear( KeyRangeRef range, const Arena* arena ) {
++writesRequested;
writeThread->post( new Writer::ClearAction(range) );
}
Future<Void> KeyValueStoreSQLite::commit(bool sequential) {
++writesRequested;
auto p = new Writer::CommitAction;
auto f = p->result.getFuture();
writeThread->post(p);
return f;
}
Future<Optional<Value>> KeyValueStoreSQLite::readValue( KeyRef key, Optional<UID> debugID ) {
++readsRequested;
auto p = new Reader::ReadValueAction(key, debugID);
auto f = p->result.getFuture();
readThreads->post(p);
return f;
}
Future<Optional<Value>> KeyValueStoreSQLite::readValuePrefix( KeyRef key, int maxLength, Optional<UID> debugID ) {
++readsRequested;
auto p = new Reader::ReadValuePrefixAction(key, maxLength, debugID);
auto f = p->result.getFuture();
readThreads->post(p);
return f;
}
Future<Standalone<VectorRef<KeyValueRef>>> KeyValueStoreSQLite::readRange( KeyRangeRef keys, int rowLimit, int byteLimit ) {
++readsRequested;
auto p = new Reader::ReadRangeAction(keys, rowLimit, byteLimit);
auto f = p->result.getFuture();
readThreads->post(p);
return f;
}
Future<KeyValueStoreSQLite::SpringCleaningWorkPerformed> KeyValueStoreSQLite::doClean() {
++writesRequested;
auto p = new Writer::SpringCleaningAction;
auto f = p->result.getFuture();
writeThread->post(p);
return f;
}
void createTemplateDatabase() {
ASSERT( !vfs_registered );
SQLiteDB db1("template.fdb", false, false);
SQLiteDB db2("template.sqlite", true, true);
db1.createFromScratch();
db2.createFromScratch();
}
void GenerateIOLogChecksumFile(std::string filename) {
if(!fileExists(filename)) {
throw file_not_found();
}
FILE *f = fopen(filename.c_str(), "r");
FILE *fout = fopen((filename + ".checksums").c_str(), "w");
uint8_t buf[4096];
unsigned int c = 0;
while(fread(buf, 1, 4096, f) > 0)
fprintf(fout, "%u %u\n", c++, hashlittle(buf, 4096, 0xab12fd93));
fclose(f);
fclose(fout);
}
// If integrity is true, a full btree integrity check is done.
// If integrity is false, only a scan of all pages to validate their checksums is done.
ACTOR Future<Void> KVFileCheck(std::string filename, bool integrity) {
if(!fileExists(filename))
throw file_not_found();
StringRef kvFile(filename);
KeyValueStoreType type = KeyValueStoreType::END;
if(kvFile.endsWith(LiteralStringRef(".fdb")))
type = KeyValueStoreType::SSD_BTREE_V1;
else if(kvFile.endsWith(LiteralStringRef(".sqlite")))
type = KeyValueStoreType::SSD_BTREE_V2;
ASSERT(type != KeyValueStoreType::END);
state IKeyValueStore* store = keyValueStoreSQLite(filename, UID(0, 0), type, !integrity, integrity);
ASSERT(store != nullptr);
// Wait for integry check to finish
wait(success(store->readValue(StringRef())));
if(store->getError().isError())
wait(store->getError());
Future<Void> c = store->onClosed();
store->close();
wait(c);
return Void();
}
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