foundationdb/fdbserver/MoveKeys.actor.cpp

1451 lines
58 KiB
C++

/*
* MoveKeys.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.
*/
#include "flow/Util.h"
#include "fdbrpc/FailureMonitor.h"
#include "fdbclient/KeyBackedTypes.h"
#include "fdbclient/SystemData.h"
#include "fdbserver/MoveKeys.actor.h"
#include "fdbserver/Knobs.h"
#include "fdbserver/TSSMappingUtil.actor.h"
#include "flow/actorcompiler.h" // This must be the last #include.
using std::max;
using std::min;
bool DDEnabledState::isDDEnabled() const {
return ddEnabled;
}
bool DDEnabledState::setDDEnabled(bool status, UID snapUID) {
TraceEvent("SetDDEnabled").detail("Status", status).detail("SnapUID", snapUID);
ASSERT(snapUID != UID());
if (!status) {
// disabling DD
if (ddEnabledStatusUID != UID()) {
// disable DD when a disable is already in progress not allowed
return false;
}
ddEnabled = status;
ddEnabledStatusUID = snapUID;
return true;
}
// enabling DD
if (snapUID != ddEnabledStatusUID) {
// enabling DD not allowed if UID does not match with the disable request
return false;
}
// reset to default status
ddEnabled = status;
ddEnabledStatusUID = UID();
return true;
}
ACTOR Future<MoveKeysLock> takeMoveKeysLock(Database cx, UID ddId) {
state Transaction tr(cx);
loop {
try {
state MoveKeysLock lock;
state UID txnId;
tr.setOption(FDBTransactionOptions::PRIORITY_SYSTEM_IMMEDIATE);
if (!g_network->isSimulated()) {
txnId = deterministicRandom()->randomUniqueID();
tr.debugTransaction(txnId);
}
{
Optional<Value> readVal = wait(tr.get(moveKeysLockOwnerKey));
lock.prevOwner =
readVal.present() ? BinaryReader::fromStringRef<UID>(readVal.get(), Unversioned()) : UID();
}
{
Optional<Value> readVal = wait(tr.get(moveKeysLockWriteKey));
lock.prevWrite =
readVal.present() ? BinaryReader::fromStringRef<UID>(readVal.get(), Unversioned()) : UID();
}
lock.myOwner = deterministicRandom()->randomUniqueID();
tr.set(moveKeysLockOwnerKey, BinaryWriter::toValue(lock.myOwner, Unversioned()));
wait(tr.commit());
TraceEvent("TakeMoveKeysLockTransaction", ddId)
.detail("TransactionUID", txnId)
.detail("PrevOwner", lock.prevOwner.toString())
.detail("PrevWrite", lock.prevWrite.toString())
.detail("MyOwner", lock.myOwner.toString());
return lock;
} catch (Error& e) {
wait(tr.onError(e));
TEST(true); // takeMoveKeysLock retry
}
}
}
ACTOR static Future<Void> checkMoveKeysLock(Transaction* tr,
MoveKeysLock lock,
const DDEnabledState* ddEnabledState,
bool isWrite = true) {
if (!ddEnabledState->isDDEnabled()) {
TraceEvent(SevDebug, "DDDisabledByInMemoryCheck");
throw movekeys_conflict();
}
Optional<Value> readVal = wait(tr->get(moveKeysLockOwnerKey));
UID currentOwner = readVal.present() ? BinaryReader::fromStringRef<UID>(readVal.get(), Unversioned()) : UID();
if (currentOwner == lock.prevOwner) {
// Check that the previous owner hasn't touched the lock since we took it
Optional<Value> readVal = wait(tr->get(moveKeysLockWriteKey));
UID lastWrite = readVal.present() ? BinaryReader::fromStringRef<UID>(readVal.get(), Unversioned()) : UID();
if (lastWrite != lock.prevWrite) {
TEST(true); // checkMoveKeysLock: Conflict with previous owner
throw movekeys_conflict();
}
// Take the lock
if (isWrite) {
BinaryWriter wrMyOwner(Unversioned());
wrMyOwner << lock.myOwner;
tr->set(moveKeysLockOwnerKey, wrMyOwner.toValue());
BinaryWriter wrLastWrite(Unversioned());
UID lastWriter = deterministicRandom()->randomUniqueID();
wrLastWrite << lastWriter;
tr->set(moveKeysLockWriteKey, wrLastWrite.toValue());
TraceEvent("CheckMoveKeysLock")
.detail("PrevOwner", lock.prevOwner.toString())
.detail("PrevWrite", lock.prevWrite.toString())
.detail("MyOwner", lock.myOwner.toString())
.detail("Writer", lastWriter.toString());
}
return Void();
} else if (currentOwner == lock.myOwner) {
if (isWrite) {
// Touch the lock, preventing overlapping attempts to take it
BinaryWriter wrLastWrite(Unversioned());
wrLastWrite << deterministicRandom()->randomUniqueID();
tr->set(moveKeysLockWriteKey, wrLastWrite.toValue());
// Make this transaction self-conflicting so the database will not execute it twice with the same write key
tr->makeSelfConflicting();
}
return Void();
} else {
TEST(true); // checkMoveKeysLock: Conflict with new owner
throw movekeys_conflict();
}
}
Future<Void> checkMoveKeysLockReadOnly(Transaction* tr, MoveKeysLock lock, const DDEnabledState* ddEnabledState) {
return checkMoveKeysLock(tr, lock, ddEnabledState, false);
}
ACTOR Future<Optional<UID>> checkReadWrite(Future<ErrorOr<GetShardStateReply>> fReply, UID uid, Version version) {
ErrorOr<GetShardStateReply> reply = wait(fReply);
if (!reply.present() || reply.get().first < version)
return Optional<UID>();
return Optional<UID>(uid);
}
Future<Void> removeOldDestinations(Reference<ReadYourWritesTransaction> tr,
UID oldDest,
VectorRef<KeyRangeRef> shards,
KeyRangeRef currentKeys) {
KeyRef beginKey = currentKeys.begin;
vector<Future<Void>> actors;
for (int i = 0; i < shards.size(); i++) {
if (beginKey < shards[i].begin)
actors.push_back(krmSetRangeCoalescing(
tr, serverKeysPrefixFor(oldDest), KeyRangeRef(beginKey, shards[i].begin), allKeys, serverKeysFalse));
beginKey = shards[i].end;
}
if (beginKey < currentKeys.end)
actors.push_back(krmSetRangeCoalescing(
tr, serverKeysPrefixFor(oldDest), KeyRangeRef(beginKey, currentKeys.end), allKeys, serverKeysFalse));
return waitForAll(actors);
}
ACTOR Future<vector<UID>> addReadWriteDestinations(KeyRangeRef shard,
vector<StorageServerInterface> srcInterfs,
vector<StorageServerInterface> destInterfs,
Version version,
int desiredHealthy,
int maxServers) {
if (srcInterfs.size() >= maxServers) {
return vector<UID>();
}
state vector<Future<Optional<UID>>> srcChecks;
srcChecks.reserve(srcInterfs.size());
for (int s = 0; s < srcInterfs.size(); s++) {
srcChecks.push_back(checkReadWrite(srcInterfs[s].getShardState.getReplyUnlessFailedFor(
GetShardStateRequest(shard, GetShardStateRequest::NO_WAIT),
SERVER_KNOBS->SERVER_READY_QUORUM_INTERVAL,
0,
TaskPriority::MoveKeys),
srcInterfs[s].id(),
0));
}
state vector<Future<Optional<UID>>> destChecks;
destChecks.reserve(destInterfs.size());
for (int s = 0; s < destInterfs.size(); s++) {
destChecks.push_back(checkReadWrite(destInterfs[s].getShardState.getReplyUnlessFailedFor(
GetShardStateRequest(shard, GetShardStateRequest::NO_WAIT),
SERVER_KNOBS->SERVER_READY_QUORUM_INTERVAL,
0,
TaskPriority::MoveKeys),
destInterfs[s].id(),
version));
}
wait(waitForAll(srcChecks) && waitForAll(destChecks));
int healthySrcs = 0;
for (auto it : srcChecks) {
if (it.get().present()) {
healthySrcs++;
}
}
vector<UID> result;
int totalDesired = std::min<int>(desiredHealthy - healthySrcs, maxServers - srcInterfs.size());
for (int s = 0; s < destInterfs.size() && result.size() < totalDesired; s++) {
if (destChecks[s].get().present()) {
result.push_back(destChecks[s].get().get());
}
}
return result;
}
ACTOR Future<vector<vector<UID>>> additionalSources(RangeResult shards,
Reference<ReadYourWritesTransaction> tr,
int desiredHealthy,
int maxServers) {
state RangeResult UIDtoTagMap = wait(tr->getRange(serverTagKeys, CLIENT_KNOBS->TOO_MANY));
ASSERT(!UIDtoTagMap.more && UIDtoTagMap.size() < CLIENT_KNOBS->TOO_MANY);
vector<Future<Optional<Value>>> serverListEntries;
std::set<UID> fetching;
for (int i = 0; i < shards.size() - 1; ++i) {
vector<UID> src;
vector<UID> dest;
decodeKeyServersValue(UIDtoTagMap, shards[i].value, src, dest);
for (int s = 0; s < src.size(); s++) {
if (!fetching.count(src[s])) {
fetching.insert(src[s]);
serverListEntries.push_back(tr->get(serverListKeyFor(src[s])));
}
}
for (int s = 0; s < dest.size(); s++) {
if (!fetching.count(dest[s])) {
fetching.insert(dest[s]);
serverListEntries.push_back(tr->get(serverListKeyFor(dest[s])));
}
}
}
vector<Optional<Value>> serverListValues = wait(getAll(serverListEntries));
std::map<UID, StorageServerInterface> ssiMap;
for (int s = 0; s < serverListValues.size(); s++) {
StorageServerInterface ssi = decodeServerListValue(serverListValues[s].get());
ssiMap[ssi.id()] = ssi;
}
vector<Future<vector<UID>>> allChecks;
for (int i = 0; i < shards.size() - 1; ++i) {
KeyRangeRef rangeIntersectKeys(shards[i].key, shards[i + 1].key);
vector<UID> src;
vector<UID> dest;
vector<StorageServerInterface> srcInterfs;
vector<StorageServerInterface> destInterfs;
decodeKeyServersValue(UIDtoTagMap, shards[i].value, src, dest);
srcInterfs.reserve(src.size());
for (int s = 0; s < src.size(); s++) {
srcInterfs.push_back(ssiMap[src[s]]);
}
for (int s = 0; s < dest.size(); s++) {
if (std::find(src.begin(), src.end(), dest[s]) == src.end()) {
destInterfs.push_back(ssiMap[dest[s]]);
}
}
allChecks.push_back(addReadWriteDestinations(
rangeIntersectKeys, srcInterfs, destInterfs, tr->getReadVersion().get(), desiredHealthy, maxServers));
}
vector<vector<UID>> result = wait(getAll(allChecks));
return result;
}
ACTOR Future<Void> logWarningAfter(const char* context, double duration, vector<UID> servers) {
state double startTime = now();
loop {
wait(delay(duration));
TraceEvent(SevWarnAlways, context).detail("Duration", now() - startTime).detail("Servers", describe(servers));
}
}
// keyServer: map from keys to destination servers
// serverKeys: two-dimension map: [servers][keys], value is the servers' state of having the keys: active(not-have),
// complete(already has), ""(). Set keyServers[keys].dest = servers Set serverKeys[servers][keys] = active for each
// subrange of keys that the server did not already have, complete for each subrange that it already has Set
// serverKeys[dest][keys] = "" for the dest servers of each existing shard in keys (unless that destination is a member
// of servers OR if the source list is sufficiently degraded)
ACTOR static Future<Void> startMoveKeys(Database occ,
KeyRange keys,
vector<UID> servers,
MoveKeysLock lock,
FlowLock* startMoveKeysLock,
UID relocationIntervalId,
std::map<UID, StorageServerInterface>* tssMapping,
const DDEnabledState* ddEnabledState) {
state TraceInterval interval("RelocateShard_StartMoveKeys");
state Future<Void> warningLogger = logWarningAfter("StartMoveKeysTooLong", 600, servers);
// state TraceInterval waitInterval("");
wait(startMoveKeysLock->take(TaskPriority::DataDistributionLaunch));
state FlowLock::Releaser releaser(*startMoveKeysLock);
state bool loadedTssMapping = false;
TraceEvent(SevDebug, interval.begin(), relocationIntervalId);
try {
state Key begin = keys.begin;
state int batches = 0;
state int shards = 0;
state int maxRetries = 0;
// If it's multiple transaction, how do we achieve atomicity?
// This process can be split up into multiple transactions if there are too many existing overlapping shards
// In that case, each iteration of this loop will have begin set to the end of the last processed shard
while (begin < keys.end) {
TEST(begin > keys.begin); // Multi-transactional startMoveKeys
batches++;
// RYW to optimize re-reading the same key ranges
state Reference<ReadYourWritesTransaction> tr = makeReference<ReadYourWritesTransaction>(occ);
state int retries = 0;
loop {
try {
retries++;
// Keep track of old dests that may need to have ranges removed from serverKeys
state std::set<UID> oldDests;
// Keep track of shards for all src servers so that we can preserve their values in serverKeys
state Map<UID, VectorRef<KeyRangeRef>> shardMap;
tr->getTransaction().info.taskID = TaskPriority::MoveKeys;
tr->setOption(FDBTransactionOptions::PRIORITY_SYSTEM_IMMEDIATE);
tr->setOption(FDBTransactionOptions::ACCESS_SYSTEM_KEYS);
wait(checkMoveKeysLock(&(tr->getTransaction()), lock, ddEnabledState));
if (!loadedTssMapping) {
// share transaction for loading tss mapping with the rest of start move keys
wait(readTSSMappingRYW(tr, tssMapping));
loadedTssMapping = true;
}
vector<Future<Optional<Value>>> serverListEntries;
serverListEntries.reserve(servers.size());
for (int s = 0; s < servers.size(); s++)
serverListEntries.push_back(tr->get(serverListKeyFor(servers[s])));
state vector<Optional<Value>> serverListValues = wait(getAll(serverListEntries));
for (int s = 0; s < serverListValues.size(); s++) {
if (!serverListValues[s].present()) {
// Attempt to move onto a server that isn't in serverList (removed or never added to the
// database) This can happen (why?) and is handled by the data distribution algorithm
// FIXME: Answer why this can happen?
TEST(true); // start move keys moving to a removed server
throw move_to_removed_server();
}
}
// Get all existing shards overlapping keys (exclude any that have been processed in a previous
// iteration of the outer loop)
state KeyRange currentKeys = KeyRangeRef(begin, keys.end);
state RangeResult old = wait(krmGetRanges(tr,
keyServersPrefix,
currentKeys,
SERVER_KNOBS->MOVE_KEYS_KRM_LIMIT,
SERVER_KNOBS->MOVE_KEYS_KRM_LIMIT_BYTES));
// Determine the last processed key (which will be the beginning for the next iteration)
state Key endKey = old.end()[-1].key;
currentKeys = KeyRangeRef(currentKeys.begin, endKey);
// TraceEvent("StartMoveKeysBatch", relocationIntervalId)
// .detail("KeyBegin", currentKeys.begin.toString())
// .detail("KeyEnd", currentKeys.end.toString());
// printf("Moving '%s'-'%s' (%d) to %d servers\n", keys.begin.toString().c_str(),
// keys.end.toString().c_str(), old.size(), servers.size()); for(int i=0; i<old.size(); i++)
// printf("'%s': '%s'\n", old[i].key.toString().c_str(), old[i].value.toString().c_str());
// Check that enough servers for each shard are in the correct state
state RangeResult UIDtoTagMap = wait(tr->getRange(serverTagKeys, CLIENT_KNOBS->TOO_MANY));
ASSERT(!UIDtoTagMap.more && UIDtoTagMap.size() < CLIENT_KNOBS->TOO_MANY);
vector<vector<UID>> addAsSource = wait(additionalSources(
old, tr, servers.size(), SERVER_KNOBS->MAX_ADDED_SOURCES_MULTIPLIER * servers.size()));
// For each intersecting range, update keyServers[range] dest to be servers and clear existing dest
// servers from serverKeys
for (int i = 0; i < old.size() - 1; ++i) {
KeyRangeRef rangeIntersectKeys(old[i].key, old[i + 1].key);
vector<UID> src;
vector<UID> dest;
decodeKeyServersValue(UIDtoTagMap, old[i].value, src, dest);
// TraceEvent("StartMoveKeysOldRange", relocationIntervalId)
// .detail("KeyBegin", rangeIntersectKeys.begin.toString())
// .detail("KeyEnd", rangeIntersectKeys.end.toString())
// .detail("OldSrc", describe(src))
// .detail("OldDest", describe(dest))
// .detail("ReadVersion", tr->getReadVersion().get());
for (auto& uid : addAsSource[i]) {
src.push_back(uid);
}
uniquify(src);
// Update dest servers for this range to be equal to servers
krmSetPreviouslyEmptyRange(&(tr->getTransaction()),
keyServersPrefix,
rangeIntersectKeys,
keyServersValue(UIDtoTagMap, src, servers),
old[i + 1].value);
// Track old destination servers. They may be removed from serverKeys soon, since they are
// about to be overwritten in keyServers
for (auto s = dest.begin(); s != dest.end(); ++s) {
oldDests.insert(*s);
// TraceEvent("StartMoveKeysOldDestAdd", relocationIntervalId).detail("Server", *s);
}
// Keep track of src shards so that we can preserve their values when we overwrite serverKeys
for (auto& uid : src) {
shardMap[uid].push_back(old.arena(), rangeIntersectKeys);
// TraceEvent("StartMoveKeysShardMapAdd", relocationIntervalId).detail("Server", uid);
}
}
state std::set<UID>::iterator oldDest;
// Remove old dests from serverKeys. In order for krmSetRangeCoalescing to work correctly in the
// same prefix for a single transaction, we must do most of the coalescing ourselves. Only the
// shards on the boundary of currentRange are actually coalesced with the ranges outside of
// currentRange. For all shards internal to currentRange, we overwrite all consecutive keys whose
// value is or should be serverKeysFalse in a single write
vector<Future<Void>> actors;
for (oldDest = oldDests.begin(); oldDest != oldDests.end(); ++oldDest)
if (std::find(servers.begin(), servers.end(), *oldDest) == servers.end())
actors.push_back(removeOldDestinations(tr, *oldDest, shardMap[*oldDest], currentKeys));
// Update serverKeys to include keys (or the currently processed subset of keys) for each SS in
// servers
for (int i = 0; i < servers.size(); i++) {
// Since we are setting this for the entire range, serverKeys and keyServers aren't guaranteed
// to have the same shard boundaries If that invariant was important, we would have to move this
// inside the loop above and also set it for the src servers
actors.push_back(krmSetRangeCoalescing(
tr, serverKeysPrefixFor(servers[i]), currentKeys, allKeys, serverKeysTrue));
}
wait(waitForAll(actors));
wait(tr->commit());
/*TraceEvent("StartMoveKeysCommitDone", relocationIntervalId)
.detail("CommitVersion", tr.getCommittedVersion())
.detail("ShardsInBatch", old.size() - 1);*/
begin = endKey;
shards += old.size() - 1;
break;
} catch (Error& e) {
state Error err = e;
if (err.code() == error_code_move_to_removed_server)
throw;
wait(tr->onError(e));
if (retries % 10 == 0) {
TraceEvent(
retries == 50 ? SevWarnAlways : SevWarn, "StartMoveKeysRetrying", relocationIntervalId)
.error(err)
.detail("Keys", keys)
.detail("BeginKey", begin)
.detail("NumTries", retries);
}
}
}
if (retries > maxRetries) {
maxRetries = retries;
}
}
// printf("Committed moving '%s'-'%s' (version %lld)\n", keys.begin.toString().c_str(),
// keys.end.toString().c_str(), tr->getCommittedVersion());
TraceEvent(SevDebug, interval.end(), relocationIntervalId)
.detail("Batches", batches)
.detail("Shards", shards)
.detail("MaxRetries", maxRetries);
} catch (Error& e) {
TraceEvent(SevDebug, interval.end(), relocationIntervalId).error(e, true);
throw;
}
return Void();
}
ACTOR Future<Void> waitForShardReady(StorageServerInterface server,
KeyRange keys,
Version minVersion,
GetShardStateRequest::waitMode mode) {
loop {
try {
GetShardStateReply rep =
wait(server.getShardState.getReply(GetShardStateRequest(keys, mode), TaskPriority::MoveKeys));
if (rep.first >= minVersion) {
return Void();
}
wait(delayJittered(SERVER_KNOBS->SHARD_READY_DELAY, TaskPriority::MoveKeys));
} catch (Error& e) {
if (e.code() != error_code_timed_out) {
if (e.code() != error_code_broken_promise)
throw e;
wait(Never()); // Never return: A storage server which has failed will never be ready
throw internal_error(); // does not happen
}
}
}
}
// best effort to also wait for TSS on data move
ACTOR Future<Void> checkFetchingState(Database cx,
vector<UID> dest,
KeyRange keys,
Promise<Void> dataMovementComplete,
UID relocationIntervalId,
std::map<UID, StorageServerInterface> tssMapping) {
state Transaction tr(cx);
loop {
try {
if (BUGGIFY)
wait(delay(5));
tr.info.taskID = TaskPriority::MoveKeys;
tr.setOption(FDBTransactionOptions::PRIORITY_SYSTEM_IMMEDIATE);
vector<Future<Optional<Value>>> serverListEntries;
serverListEntries.reserve(dest.size());
for (int s = 0; s < dest.size(); s++)
serverListEntries.push_back(tr.get(serverListKeyFor(dest[s])));
state vector<Optional<Value>> serverListValues = wait(getAll(serverListEntries));
vector<Future<Void>> requests;
state vector<Future<Void>> tssRequests;
for (int s = 0; s < serverListValues.size(); s++) {
if (!serverListValues[s].present()) {
// FIXME: Is this the right behavior? dataMovementComplete will never be sent!
TEST(true); // check fetching state moved to removed server
throw move_to_removed_server();
}
auto si = decodeServerListValue(serverListValues[s].get());
ASSERT(si.id() == dest[s]);
requests.push_back(
waitForShardReady(si, keys, tr.getReadVersion().get(), GetShardStateRequest::FETCHING));
auto tssPair = tssMapping.find(si.id());
if (tssPair != tssMapping.end()) {
tssRequests.push_back(waitForShardReady(
tssPair->second, keys, tr.getReadVersion().get(), GetShardStateRequest::FETCHING));
}
}
wait(timeoutError(waitForAll(requests), SERVER_KNOBS->SERVER_READY_QUORUM_TIMEOUT, TaskPriority::MoveKeys));
// If normal servers return normally, give TSS data movement a bit of a chance, but don't block on it, and
// ignore errors in tss requests
if (tssRequests.size()) {
wait(timeout(waitForAllReady(tssRequests),
SERVER_KNOBS->SERVER_READY_QUORUM_TIMEOUT / 2,
Void(),
TaskPriority::MoveKeys));
}
dataMovementComplete.send(Void());
return Void();
} catch (Error& e) {
if (e.code() == error_code_timed_out)
tr.reset();
else
wait(tr.onError(e));
}
}
}
// Set keyServers[keys].src = keyServers[keys].dest and keyServers[keys].dest=[], return when successful
// keyServers[k].dest must be the same for all k in keys
// Set serverKeys[dest][keys] = true; serverKeys[src][keys] = false for all src not in dest
// Should be cancelled and restarted if keyServers[keys].dest changes (?so this is no longer true?)
ACTOR static Future<Void> finishMoveKeys(Database occ,
KeyRange keys,
vector<UID> destinationTeam,
MoveKeysLock lock,
FlowLock* finishMoveKeysParallelismLock,
bool hasRemote,
UID relocationIntervalId,
std::map<UID, StorageServerInterface> tssMapping,
const DDEnabledState* ddEnabledState) {
state TraceInterval interval("RelocateShard_FinishMoveKeys");
state TraceInterval waitInterval("");
state Future<Void> warningLogger = logWarningAfter("FinishMoveKeysTooLong", 600, destinationTeam);
state Key begin = keys.begin;
state Key endKey;
state int retries = 0;
state FlowLock::Releaser releaser;
state std::vector<std::pair<UID, UID>> tssToKill;
state std::unordered_set<UID> tssToIgnore;
// try waiting for tss for a 2 loops, give up if they're stuck to not affect the rest of the cluster
state int waitForTSSCounter = 2;
ASSERT(!destinationTeam.empty());
try {
TraceEvent(SevDebug, interval.begin(), relocationIntervalId)
.detail("KeyBegin", keys.begin)
.detail("KeyEnd", keys.end);
// This process can be split up into multiple transactions if there are too many existing overlapping shards
// In that case, each iteration of this loop will have begin set to the end of the last processed shard
while (begin < keys.end) {
TEST(begin > keys.begin); // Multi-transactional finishMoveKeys
state Transaction tr(occ);
// printf("finishMoveKeys( '%s'-'%s' )\n", begin.toString().c_str(), keys.end.toString().c_str());
loop {
try {
if (tssToKill.size()) {
TEST(true); // killing TSS because they were unavailable for movekeys
// Kill tss BEFORE committing main txn so that client requests don't make it to the tss when it
// has a different shard set than its pair use a different RYW transaction since i'm too lazy
// (and don't want to add bugs) by changing whole method to RYW. Also, using a different
// transaction makes it commit earlier which we may need to guarantee causality of tss getting
// removed before client sends a request to this key range on the new SS
wait(removeTSSPairsFromCluster(occ, tssToKill));
for (auto& tssPair : tssToKill) {
TraceEvent(SevWarnAlways, "TSS_KillMoveKeys").detail("TSSID", tssPair.second);
tssToIgnore.insert(tssPair.second);
}
tssToKill.clear();
}
tr.info.taskID = TaskPriority::MoveKeys;
tr.setOption(FDBTransactionOptions::PRIORITY_SYSTEM_IMMEDIATE);
releaser.release();
wait(finishMoveKeysParallelismLock->take(TaskPriority::DataDistributionLaunch));
releaser = FlowLock::Releaser(*finishMoveKeysParallelismLock);
wait(checkMoveKeysLock(&tr, lock, ddEnabledState));
state KeyRange currentKeys = KeyRangeRef(begin, keys.end);
state RangeResult UIDtoTagMap = wait(tr.getRange(serverTagKeys, CLIENT_KNOBS->TOO_MANY));
ASSERT(!UIDtoTagMap.more && UIDtoTagMap.size() < CLIENT_KNOBS->TOO_MANY);
state RangeResult keyServers = wait(krmGetRanges(&tr,
keyServersPrefix,
currentKeys,
SERVER_KNOBS->MOVE_KEYS_KRM_LIMIT,
SERVER_KNOBS->MOVE_KEYS_KRM_LIMIT_BYTES));
// Determine the last processed key (which will be the beginning for the next iteration)
endKey = keyServers.end()[-1].key;
currentKeys = KeyRangeRef(currentKeys.begin, endKey);
// printf(" finishMoveKeys( '%s'-'%s' ): read keyServers at %lld\n", keys.begin.toString().c_str(),
// keys.end.toString().c_str(), tr.getReadVersion().get());
// Decode and sanity check the result (dest must be the same for all ranges)
bool alreadyMoved = true;
state vector<UID> dest;
state std::set<UID> allServers;
state std::set<UID> intendedTeam(destinationTeam.begin(), destinationTeam.end());
state vector<UID> src;
vector<UID> completeSrc;
// Iterate through the beginning of keyServers until we find one that hasn't already been processed
int currentIndex;
for (currentIndex = 0; currentIndex < keyServers.size() - 1 && alreadyMoved; currentIndex++) {
decodeKeyServersValue(UIDtoTagMap, keyServers[currentIndex].value, src, dest);
std::set<UID> srcSet;
for (int s = 0; s < src.size(); s++) {
srcSet.insert(src[s]);
}
if (currentIndex == 0) {
completeSrc = src;
} else {
for (int i = 0; i < completeSrc.size(); i++) {
if (!srcSet.count(completeSrc[i])) {
swapAndPop(&completeSrc, i--);
}
}
}
std::set<UID> destSet;
for (int s = 0; s < dest.size(); s++) {
destSet.insert(dest[s]);
}
allServers.insert(srcSet.begin(), srcSet.end());
allServers.insert(destSet.begin(), destSet.end());
// Because marking a server as failed can shrink a team, do not check for exact equality
// Instead, check for a subset of the intended team, which also covers the equality case
bool isSubset =
std::includes(intendedTeam.begin(), intendedTeam.end(), srcSet.begin(), srcSet.end());
alreadyMoved = destSet.empty() && isSubset;
if (destSet != intendedTeam && !alreadyMoved) {
TraceEvent(SevWarn, "MoveKeysDestTeamNotIntended", relocationIntervalId)
.detail("KeyBegin", keys.begin)
.detail("KeyEnd", keys.end)
.detail("IterationBegin", begin)
.detail("IterationEnd", endKey)
.detail("SrcSet", describe(srcSet))
.detail("DestSet", describe(destSet))
.detail("IntendedTeam", describe(intendedTeam))
.detail("KeyServers", keyServers);
// ASSERT( false );
ASSERT(!dest.empty()); // The range has already been moved, but to a different dest (or
// maybe dest was cleared)
intendedTeam.clear();
for (int i = 0; i < dest.size(); i++)
intendedTeam.insert(dest[i]);
} else if (alreadyMoved) {
dest.clear();
src.clear();
TEST(true); // FinishMoveKeys first key in iteration sub-range has already been processed
}
}
// Process the rest of the key servers
for (; currentIndex < keyServers.size() - 1; currentIndex++) {
vector<UID> src2, dest2;
decodeKeyServersValue(UIDtoTagMap, keyServers[currentIndex].value, src2, dest2);
std::set<UID> srcSet;
for (int s = 0; s < src2.size(); s++)
srcSet.insert(src2[s]);
for (int i = 0; i < completeSrc.size(); i++) {
if (!srcSet.count(completeSrc[i])) {
swapAndPop(&completeSrc, i--);
}
}
allServers.insert(srcSet.begin(), srcSet.end());
// Because marking a server as failed can shrink a team, do not check for exact equality
// Instead, check for a subset of the intended team, which also covers the equality case
bool isSubset =
std::includes(intendedTeam.begin(), intendedTeam.end(), srcSet.begin(), srcSet.end());
alreadyMoved = dest2.empty() && isSubset;
if (dest2 != dest && !alreadyMoved) {
TraceEvent(SevError, "FinishMoveKeysError", relocationIntervalId)
.detail("Reason", "dest mismatch")
.detail("Dest", describe(dest))
.detail("Dest2", describe(dest2));
ASSERT(false);
}
}
if (!dest.size()) {
TEST(true); // A previous finishMoveKeys for this range committed just as it was cancelled to
// start this one?
TraceEvent("FinishMoveKeysNothingToDo", relocationIntervalId)
.detail("KeyBegin", keys.begin)
.detail("KeyEnd", keys.end)
.detail("IterationBegin", begin)
.detail("IterationEnd", endKey);
begin = keyServers.end()[-1].key;
break;
}
waitInterval = TraceInterval("RelocateShard_FinishMoveKeysWaitDurable");
TraceEvent(SevDebug, waitInterval.begin(), relocationIntervalId)
.detail("KeyBegin", keys.begin)
.detail("KeyEnd", keys.end);
// Wait for a durable quorum of servers in destServers to have keys available (readWrite)
// They must also have at least the transaction read version so they can't "forget" the shard
// between
// now and when this transaction commits.
state vector<Future<Void>> serverReady; // only for count below
state vector<Future<Void>> tssReady; // for waiting in parallel with tss
state vector<StorageServerInterface> tssReadyInterfs;
state vector<UID> newDestinations;
std::set<UID> completeSrcSet(completeSrc.begin(), completeSrc.end());
for (auto& it : dest) {
if (!hasRemote || !completeSrcSet.count(it)) {
newDestinations.push_back(it);
}
}
// for smartQuorum
state vector<StorageServerInterface> storageServerInterfaces;
vector<Future<Optional<Value>>> serverListEntries;
serverListEntries.reserve(newDestinations.size());
for (int s = 0; s < newDestinations.size(); s++)
serverListEntries.push_back(tr.get(serverListKeyFor(newDestinations[s])));
state vector<Optional<Value>> serverListValues = wait(getAll(serverListEntries));
releaser.release();
for (int s = 0; s < serverListValues.size(); s++) {
ASSERT(serverListValues[s]
.present()); // There should always be server list entries for servers in keyServers
auto si = decodeServerListValue(serverListValues[s].get());
ASSERT(si.id() == newDestinations[s]);
storageServerInterfaces.push_back(si);
}
// update client info in case tss mapping changed or server got updated
// Wait for new destination servers to fetch the keys
serverReady.reserve(storageServerInterfaces.size());
tssReady.reserve(storageServerInterfaces.size());
tssReadyInterfs.reserve(storageServerInterfaces.size());
for (int s = 0; s < storageServerInterfaces.size(); s++) {
serverReady.push_back(waitForShardReady(storageServerInterfaces[s],
keys,
tr.getReadVersion().get(),
GetShardStateRequest::READABLE));
auto tssPair = tssMapping.find(storageServerInterfaces[s].id());
if (tssPair != tssMapping.end() && waitForTSSCounter > 0 &&
!tssToIgnore.count(tssPair->second.id())) {
tssReadyInterfs.push_back(tssPair->second);
tssReady.push_back(waitForShardReady(
tssPair->second, keys, tr.getReadVersion().get(), GetShardStateRequest::READABLE));
}
}
// Wait for all storage server moves, and explicitly swallow errors for tss ones with
// waitForAllReady If this takes too long the transaction will time out and retry, which is ok
wait(timeout(waitForAll(serverReady) && waitForAllReady(tssReady),
SERVER_KNOBS->SERVER_READY_QUORUM_TIMEOUT,
Void(),
TaskPriority::MoveKeys));
// Check to see if we're waiting only on tss. If so, decrement the waiting counter.
// If the waiting counter is zero, kill the slow/non-responsive tss processes before finalizing the
// data move.
if (tssReady.size()) {
bool allSSDone = true;
for (auto& f : serverReady) {
allSSDone &= f.isReady() && !f.isError();
if (!allSSDone) {
break;
}
}
if (allSSDone) {
bool anyTssNotDone = false;
for (auto& f : tssReady) {
if (!f.isReady() || f.isError()) {
anyTssNotDone = true;
waitForTSSCounter--;
break;
}
}
if (anyTssNotDone && waitForTSSCounter == 0) {
for (int i = 0; i < tssReady.size(); i++) {
if (!tssReady[i].isReady() || tssReady[i].isError()) {
tssToKill.push_back(
std::pair(tssReadyInterfs[i].tssPairID.get(), tssReadyInterfs[i].id()));
}
}
// repeat loop and go back to start to kill tss' before continuing on
continue;
}
}
}
int count = dest.size() - newDestinations.size();
for (int s = 0; s < serverReady.size(); s++)
count += serverReady[s].isReady() && !serverReady[s].isError();
int tssCount = 0;
for (int s = 0; s < tssReady.size(); s++)
tssCount += tssReady[s].isReady() && !tssReady[s].isError();
/*if (tssReady.size()) {
printf(" fMK: [%s - %s) moved data to %d/%d servers and %d/%d tss\n",
begin.toString().c_str(),
keys.end.toString().c_str(),
count,
serverReady.size(),
tssCount,
tssReady.size());
} else {
printf(" fMK: [%s - %s) moved data to %d/%d servers\n",
begin.toString().c_str(),
keys.end.toString().c_str(),
count,
serverReady.size());
}*/
TraceEvent(SevDebug, waitInterval.end(), relocationIntervalId).detail("ReadyServers", count);
if (count == dest.size()) {
// update keyServers, serverKeys
// SOMEDAY: Doing these in parallel is safe because none of them overlap or touch (one per
// server)
wait(krmSetRangeCoalescing(
&tr, keyServersPrefix, currentKeys, keys, keyServersValue(UIDtoTagMap, dest)));
std::set<UID>::iterator asi = allServers.begin();
std::vector<Future<Void>> actors;
while (asi != allServers.end()) {
bool destHasServer = std::find(dest.begin(), dest.end(), *asi) != dest.end();
actors.push_back(krmSetRangeCoalescing(&tr,
serverKeysPrefixFor(*asi),
currentKeys,
allKeys,
destHasServer ? serverKeysTrue : serverKeysFalse));
++asi;
}
wait(waitForAll(actors));
wait(tr.commit());
begin = endKey;
break;
}
tr.reset();
} catch (Error& error) {
if (error.code() == error_code_actor_cancelled)
throw;
state Error err = error;
wait(tr.onError(error));
retries++;
if (retries % 10 == 0) {
TraceEvent(retries == 20 ? SevWarnAlways : SevWarn,
"RelocateShard_FinishMoveKeysRetrying",
relocationIntervalId)
.error(err)
.detail("KeyBegin", keys.begin)
.detail("KeyEnd", keys.end)
.detail("IterationBegin", begin)
.detail("IterationEnd", endKey);
}
}
}
}
TraceEvent(SevDebug, interval.end(), relocationIntervalId);
} catch (Error& e) {
TraceEvent(SevDebug, interval.end(), relocationIntervalId).error(e, true);
throw;
}
return Void();
}
ACTOR Future<std::pair<Version, Tag>> addStorageServer(Database cx, StorageServerInterface server) {
state Reference<ReadYourWritesTransaction> tr = makeReference<ReadYourWritesTransaction>(cx);
state KeyBackedMap<UID, UID> tssMapDB = KeyBackedMap<UID, UID>(tssMappingKeys.begin);
state int maxSkipTags = 1;
loop {
try {
tr->setOption(FDBTransactionOptions::ACCESS_SYSTEM_KEYS);
// FIXME: don't fetch tag localities, all tags, and history tags if tss. Just fetch pair's tag
state Future<RangeResult> fTagLocalities = tr->getRange(tagLocalityListKeys, CLIENT_KNOBS->TOO_MANY);
state Future<Optional<Value>> fv = tr->get(serverListKeyFor(server.id()));
state Future<Optional<Value>> fExclProc = tr->get(
StringRef(encodeExcludedServersKey(AddressExclusion(server.address().ip, server.address().port))));
state Future<Optional<Value>> fExclIP =
tr->get(StringRef(encodeExcludedServersKey(AddressExclusion(server.address().ip))));
state Future<Optional<Value>> fFailProc = tr->get(
StringRef(encodeFailedServersKey(AddressExclusion(server.address().ip, server.address().port))));
state Future<Optional<Value>> fFailIP =
tr->get(StringRef(encodeFailedServersKey(AddressExclusion(server.address().ip))));
state Future<Optional<Value>> fExclProc2 =
server.secondaryAddress().present()
? tr->get(StringRef(encodeExcludedServersKey(
AddressExclusion(server.secondaryAddress().get().ip, server.secondaryAddress().get().port))))
: Future<Optional<Value>>(Optional<Value>());
state Future<Optional<Value>> fExclIP2 =
server.secondaryAddress().present()
? tr->get(StringRef(encodeExcludedServersKey(AddressExclusion(server.secondaryAddress().get().ip))))
: Future<Optional<Value>>(Optional<Value>());
state Future<Optional<Value>> fFailProc2 =
server.secondaryAddress().present()
? tr->get(StringRef(encodeFailedServersKey(
AddressExclusion(server.secondaryAddress().get().ip, server.secondaryAddress().get().port))))
: Future<Optional<Value>>(Optional<Value>());
state Future<Optional<Value>> fFailIP2 =
server.secondaryAddress().present()
? tr->get(StringRef(encodeFailedServersKey(AddressExclusion(server.secondaryAddress().get().ip))))
: Future<Optional<Value>>(Optional<Value>());
state Future<RangeResult> fTags = tr->getRange(serverTagKeys, CLIENT_KNOBS->TOO_MANY, true);
state Future<RangeResult> fHistoryTags = tr->getRange(serverTagHistoryKeys, CLIENT_KNOBS->TOO_MANY, true);
wait(success(fTagLocalities) && success(fv) && success(fTags) && success(fHistoryTags) &&
success(fExclProc) && success(fExclIP) && success(fFailProc) && success(fFailIP) &&
success(fExclProc2) && success(fExclIP2) && success(fFailProc2) && success(fFailIP2));
// If we have been added to the excluded/failed state servers list, we have to fail
if (fExclProc.get().present() || fExclIP.get().present() || fFailProc.get().present() ||
fFailIP.get().present() || fExclProc2.get().present() || fExclIP2.get().present() ||
fFailProc2.get().present() || fFailIP2.get().present()) {
throw recruitment_failed();
}
if (fTagLocalities.get().more || fTags.get().more || fHistoryTags.get().more)
ASSERT(false);
state Tag tag;
if (server.isTss()) {
bool foundTag = false;
for (auto& it : fTags.get()) {
UID key = decodeServerTagKey(it.key);
if (key == server.tssPairID.get()) {
tag = decodeServerTagValue(it.value);
foundTag = true;
break;
}
}
if (!foundTag) {
throw recruitment_failed();
}
tssMapDB.set(tr, server.tssPairID.get(), server.id());
} else {
int8_t maxTagLocality = 0;
state int8_t locality = -1;
for (auto& kv : fTagLocalities.get()) {
int8_t loc = decodeTagLocalityListValue(kv.value);
if (decodeTagLocalityListKey(kv.key) == server.locality.dcId()) {
locality = loc;
break;
}
maxTagLocality = std::max(maxTagLocality, loc);
}
if (locality == -1) {
locality = maxTagLocality + 1;
if (locality < 0) {
throw recruitment_failed();
}
tr->set(tagLocalityListKeyFor(server.locality.dcId()), tagLocalityListValue(locality));
}
int skipTags = deterministicRandom()->randomInt(0, maxSkipTags);
state uint16_t tagId = 0;
std::vector<uint16_t> usedTags;
for (auto& it : fTags.get()) {
Tag t = decodeServerTagValue(it.value);
if (t.locality == locality) {
usedTags.push_back(t.id);
}
}
for (auto& it : fHistoryTags.get()) {
Tag t = decodeServerTagValue(it.value);
if (t.locality == locality) {
usedTags.push_back(t.id);
}
}
std::sort(usedTags.begin(), usedTags.end());
int usedIdx = 0;
for (; usedTags.size() > 0 && tagId <= usedTags.end()[-1]; tagId++) {
if (tagId < usedTags[usedIdx]) {
if (skipTags == 0)
break;
skipTags--;
} else {
usedIdx++;
}
}
tagId += skipTags;
tag = Tag(locality, tagId);
tr->set(serverTagKeyFor(server.id()), serverTagValue(tag));
KeyRange conflictRange = singleKeyRange(serverTagConflictKeyFor(tag));
tr->addReadConflictRange(conflictRange);
tr->addWriteConflictRange(conflictRange);
if (SERVER_KNOBS->TSS_HACK_IDENTITY_MAPPING) {
// THIS SHOULD NEVER BE ENABLED IN ANY NON-TESTING ENVIRONMENT
TraceEvent(SevError, "TSSIdentityMappingEnabled");
tssMapDB.set(tr, server.id(), server.id());
}
}
tr->set(serverListKeyFor(server.id()), serverListValue(server));
wait(tr->commit());
return std::make_pair(tr->getCommittedVersion(), tag);
} catch (Error& e) {
if (e.code() == error_code_commit_unknown_result)
throw recruitment_failed(); // There is a remote possibility that we successfully added ourselves and
// then someone removed us, so we have to fail
if (e.code() == error_code_not_committed) {
maxSkipTags = SERVER_KNOBS->MAX_SKIP_TAGS;
}
wait(tr->onError(e));
}
}
}
// A SS can be removed only if all data (shards) on the SS have been moved away from the SS.
ACTOR Future<bool> canRemoveStorageServer(Reference<ReadYourWritesTransaction> tr, UID serverID) {
RangeResult keys = wait(krmGetRanges(tr, serverKeysPrefixFor(serverID), allKeys, 2));
ASSERT(keys.size() >= 2);
if (keys[0].value == keys[1].value && keys[1].key != allKeys.end) {
TraceEvent("ServerKeysCoalescingError", serverID)
.detail("Key1", keys[0].key)
.detail("Key2", keys[1].key)
.detail("Value", keys[0].value);
ASSERT(false);
}
// Return true if the entire range is false. Since these values are coalesced, we can return false if there is more
// than one result
return keys[0].value == serverKeysFalse && keys[1].key == allKeys.end;
}
ACTOR Future<Void> removeStorageServer(Database cx,
UID serverID,
Optional<UID> tssPairID,
MoveKeysLock lock,
const DDEnabledState* ddEnabledState) {
state KeyBackedMap<UID, UID> tssMapDB = KeyBackedMap<UID, UID>(tssMappingKeys.begin);
state Reference<ReadYourWritesTransaction> tr = makeReference<ReadYourWritesTransaction>(cx);
state bool retry = false;
state int noCanRemoveCount = 0;
loop {
try {
tr->setOption(FDBTransactionOptions::PRIORITY_SYSTEM_IMMEDIATE);
tr->setOption(FDBTransactionOptions::ACCESS_SYSTEM_KEYS);
wait(checkMoveKeysLock(&(tr->getTransaction()), lock, ddEnabledState));
TraceEvent("RemoveStorageServerLocked")
.detail("ServerID", serverID)
.detail("Version", tr->getReadVersion().get());
state bool canRemove = wait(canRemoveStorageServer(tr, serverID));
if (!canRemove) {
TEST(true); // The caller had a transaction in flight that assigned keys to the server. Wait for it to
// reverse its mistake.
TraceEvent(SevWarn, "NoCanRemove").detail("Count", noCanRemoveCount++).detail("ServerID", serverID);
wait(delayJittered(SERVER_KNOBS->REMOVE_RETRY_DELAY, TaskPriority::DataDistributionLaunch));
tr->reset();
TraceEvent("RemoveStorageServerRetrying").detail("CanRemove", canRemove);
} else {
state Future<Optional<Value>> fListKey = tr->get(serverListKeyFor(serverID));
state Future<RangeResult> fTags = tr->getRange(serverTagKeys, CLIENT_KNOBS->TOO_MANY);
state Future<RangeResult> fHistoryTags = tr->getRange(serverTagHistoryKeys, CLIENT_KNOBS->TOO_MANY);
state Future<RangeResult> fTagLocalities = tr->getRange(tagLocalityListKeys, CLIENT_KNOBS->TOO_MANY);
state Future<RangeResult> fTLogDatacenters = tr->getRange(tLogDatacentersKeys, CLIENT_KNOBS->TOO_MANY);
wait(success(fListKey) && success(fTags) && success(fHistoryTags) && success(fTagLocalities) &&
success(fTLogDatacenters));
if (!fListKey.get().present()) {
if (retry) {
TEST(true); // Storage server already removed after retrying transaction
return Void();
}
ASSERT(false); // Removing an already-removed server? A never added server?
}
int8_t locality = -100;
std::set<int8_t> allLocalities;
for (auto& it : fTags.get()) {
UID sId = decodeServerTagKey(it.key);
Tag t = decodeServerTagValue(it.value);
if (sId == serverID) {
locality = t.locality;
} else {
allLocalities.insert(t.locality);
}
}
for (auto& it : fHistoryTags.get()) {
Tag t = decodeServerTagValue(it.value);
allLocalities.insert(t.locality);
}
std::map<Optional<Value>, int8_t> dcId_locality;
for (auto& kv : fTagLocalities.get()) {
dcId_locality[decodeTagLocalityListKey(kv.key)] = decodeTagLocalityListValue(kv.value);
}
for (auto& it : fTLogDatacenters.get()) {
allLocalities.insert(dcId_locality[decodeTLogDatacentersKey(it.key)]);
}
if (locality >= 0 && !allLocalities.count(locality)) {
for (auto& it : fTagLocalities.get()) {
if (locality == decodeTagLocalityListValue(it.value)) {
tr->clear(it.key);
break;
}
}
}
tr->clear(serverListKeyFor(serverID));
tr->clear(serverTagKeyFor(serverID)); // A tss uses this to communicate shutdown but it never has a
// server tag key set in the first place
tr->clear(serverTagHistoryRangeFor(serverID));
if (SERVER_KNOBS->TSS_HACK_IDENTITY_MAPPING) {
// THIS SHOULD NEVER BE ENABLED IN ANY NON-TESTING ENVIRONMENT
TraceEvent(SevError, "TSSIdentityMappingEnabled");
tssMapDB.erase(tr, serverID);
} else if (tssPairID.present()) {
// remove the TSS from the mapping
tssMapDB.erase(tr, tssPairID.get());
// remove the TSS from quarantine, if it was in quarantine
Key tssQuarantineKey = tssQuarantineKeyFor(serverID);
Optional<Value> tssInQuarantine = wait(tr->get(tssQuarantineKey));
if (tssInQuarantine.present()) {
tr->clear(tssQuarantineKeyFor(serverID));
}
}
retry = true;
wait(tr->commit());
return Void();
}
} catch (Error& e) {
state Error err = e;
wait(tr->onError(e));
TraceEvent("RemoveStorageServerRetrying").error(err);
}
}
}
// Remove the server from keyServer list and set serverKeysFalse to the server's serverKeys list.
// Changes to keyServer and serverKey must happen symmetrically in a transaction.
ACTOR Future<Void> removeKeysFromFailedServer(Database cx,
UID serverID,
MoveKeysLock lock,
const DDEnabledState* ddEnabledState) {
state Key begin = allKeys.begin;
// Multi-transactional removal in case of large number of shards, concern in violating 5s transaction limit
while (begin < allKeys.end) {
state Transaction tr(cx);
loop {
try {
tr.info.taskID = TaskPriority::MoveKeys;
tr.setOption(FDBTransactionOptions::PRIORITY_SYSTEM_IMMEDIATE);
wait(checkMoveKeysLock(&tr, lock, ddEnabledState));
TraceEvent("RemoveKeysFromFailedServerLocked")
.detail("ServerID", serverID)
.detail("Version", tr.getReadVersion().get())
.detail("Begin", begin);
// Get all values of keyServers and remove serverID from every occurrence
// Very inefficient going over every entry in keyServers
// No shortcut because keyServers and serverKeys are not guaranteed same shard boundaries
state RangeResult UIDtoTagMap = wait(tr.getRange(serverTagKeys, CLIENT_KNOBS->TOO_MANY));
ASSERT(!UIDtoTagMap.more && UIDtoTagMap.size() < CLIENT_KNOBS->TOO_MANY);
state RangeResult keyServers = wait(krmGetRanges(&tr,
keyServersPrefix,
KeyRangeRef(begin, allKeys.end),
SERVER_KNOBS->MOVE_KEYS_KRM_LIMIT,
SERVER_KNOBS->MOVE_KEYS_KRM_LIMIT_BYTES));
state KeyRange currentKeys = KeyRangeRef(begin, keyServers.end()[-1].key);
for (int i = 0; i < keyServers.size() - 1; ++i) {
auto it = keyServers[i];
vector<UID> src;
vector<UID> dest;
decodeKeyServersValue(UIDtoTagMap, it.value, src, dest);
// The failed server is not present
if (std::find(src.begin(), src.end(), serverID) == src.end() &&
std::find(dest.begin(), dest.end(), serverID) == dest.end()) {
continue;
}
// Update the vectors to remove failed server then set the value again
// Dest is usually empty, but keep this in case there is parallel data movement
src.erase(std::remove(src.begin(), src.end(), serverID), src.end());
dest.erase(std::remove(dest.begin(), dest.end(), serverID), dest.end());
TraceEvent(SevDebug, "FailedServerSetKey", serverID)
.detail("Key", it.key)
.detail("ValueSrc", describe(src))
.detail("ValueDest", describe(dest));
tr.set(keyServersKey(it.key), keyServersValue(UIDtoTagMap, src, dest));
}
// Set entire range for our serverID in serverKeys keyspace to false to signal erasure
TraceEvent(SevDebug, "FailedServerSetRange", serverID)
.detail("Begin", currentKeys.begin)
.detail("End", currentKeys.end);
wait(krmSetRangeCoalescing(&tr, serverKeysPrefixFor(serverID), currentKeys, allKeys, serverKeysFalse));
wait(tr.commit());
TraceEvent(SevDebug, "FailedServerCommitSuccess", serverID)
.detail("Begin", currentKeys.begin)
.detail("End", currentKeys.end)
.detail("CommitVersion", tr.getCommittedVersion());
// Update beginning of next iteration's range
begin = currentKeys.end;
break;
} catch (Error& e) {
TraceEvent("FailedServerError", serverID).error(e);
wait(tr.onError(e));
}
}
}
return Void();
}
ACTOR Future<Void> moveKeys(Database cx,
KeyRange keys,
vector<UID> destinationTeam,
vector<UID> healthyDestinations,
MoveKeysLock lock,
Promise<Void> dataMovementComplete,
FlowLock* startMoveKeysParallelismLock,
FlowLock* finishMoveKeysParallelismLock,
bool hasRemote,
UID relocationIntervalId,
const DDEnabledState* ddEnabledState) {
ASSERT(destinationTeam.size());
std::sort(destinationTeam.begin(), destinationTeam.end());
state std::map<UID, StorageServerInterface> tssMapping;
wait(startMoveKeys(cx,
keys,
destinationTeam,
lock,
startMoveKeysParallelismLock,
relocationIntervalId,
&tssMapping,
ddEnabledState));
state Future<Void> completionSignaller =
checkFetchingState(cx, healthyDestinations, keys, dataMovementComplete, relocationIntervalId, tssMapping);
wait(finishMoveKeys(cx,
keys,
destinationTeam,
lock,
finishMoveKeysParallelismLock,
hasRemote,
relocationIntervalId,
tssMapping,
ddEnabledState));
// This is defensive, but make sure that we always say that the movement is complete before moveKeys completes
completionSignaller.cancel();
if (!dataMovementComplete.isSet())
dataMovementComplete.send(Void());
return Void();
}
// Called by the master server to write the very first transaction to the database
// establishing a set of shard servers and all invariants of the systemKeys.
void seedShardServers(Arena& arena, CommitTransactionRef& tr, vector<StorageServerInterface> servers) {
std::map<Optional<Value>, Tag> dcId_locality;
std::map<UID, Tag> server_tag;
int8_t nextLocality = 0;
for (auto& s : servers) {
if (!dcId_locality.count(s.locality.dcId())) {
tr.set(arena, tagLocalityListKeyFor(s.locality.dcId()), tagLocalityListValue(nextLocality));
dcId_locality[s.locality.dcId()] = Tag(nextLocality, 0);
nextLocality++;
}
Tag& t = dcId_locality[s.locality.dcId()];
server_tag[s.id()] = Tag(t.locality, t.id);
t.id++;
}
std::sort(servers.begin(), servers.end());
// This isn't strictly necessary, but make sure this is the first transaction
tr.read_snapshot = 0;
tr.read_conflict_ranges.push_back_deep(arena, allKeys);
for (auto& s : servers) {
tr.set(arena, serverTagKeyFor(s.id()), serverTagValue(server_tag[s.id()]));
tr.set(arena, serverListKeyFor(s.id()), serverListValue(s));
if (SERVER_KNOBS->TSS_HACK_IDENTITY_MAPPING) {
// THIS SHOULD NEVER BE ENABLED IN ANY NON-TESTING ENVIRONMENT
TraceEvent(SevError, "TSSIdentityMappingEnabled");
// hack key-backed map here since we can't really change CommitTransactionRef to a RYW transaction
Key uidRef = Codec<UID>::pack(s.id()).pack();
tr.set(arena, uidRef.withPrefix(tssMappingKeys.begin), uidRef);
}
}
std::vector<Tag> serverTags;
std::vector<UID> serverSrcUID;
serverTags.reserve(servers.size());
for (auto& s : servers) {
serverTags.push_back(server_tag[s.id()]);
serverSrcUID.push_back(s.id());
}
auto ksValue = CLIENT_KNOBS->TAG_ENCODE_KEY_SERVERS ? keyServersValue(serverTags)
: keyServersValue(RangeResult(), serverSrcUID);
// We have to set this range in two blocks, because the master tracking of "keyServersLocations" depends on a change
// to a specific
// key (keyServersKeyServersKey)
krmSetPreviouslyEmptyRange(tr, arena, keyServersPrefix, KeyRangeRef(KeyRef(), allKeys.end), ksValue, Value());
for (auto& s : servers) {
krmSetPreviouslyEmptyRange(tr, arena, serverKeysPrefixFor(s.id()), allKeys, serverKeysTrue, serverKeysFalse);
}
}