foundationdb/fdbserver/BlobManager.actor.cpp

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/*
* BlobManager.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.
*/
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#include <vector>
#include <unordered_map>
#include "contrib/fmt-8.0.1/include/fmt/format.h"
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#include "fdbclient/BlobGranuleCommon.h"
#include "fdbclient/BlobWorkerInterface.h"
#include "fdbclient/KeyRangeMap.h"
#include "fdbclient/ReadYourWrites.h"
#include "fdbclient/SystemData.h"
#include "fdbserver/BlobManagerInterface.h"
#include "fdbserver/Knobs.h"
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#include "fdbserver/QuietDatabase.h"
#include "fdbserver/WaitFailure.h"
#include "fdbserver/WorkerInterface.actor.h"
#include "flow/IRandom.h"
#include "flow/UnitTest.h"
#include "flow/actorcompiler.h" // has to be last include
#define BM_DEBUG true
// FIXME: change all BlobManagerData* to Reference<BlobManagerData> to avoid segfaults if core loop gets error
// TODO add comments + documentation
void handleClientBlobRange(KeyRangeMap<bool>* knownBlobRanges,
Arena& ar,
VectorRef<KeyRangeRef>* rangesToAdd,
VectorRef<KeyRangeRef>* rangesToRemove,
KeyRef rangeStart,
KeyRef rangeEnd,
bool rangeActive) {
if (BM_DEBUG) {
printf("db range [%s - %s): %s\n",
rangeStart.printable().c_str(),
rangeEnd.printable().c_str(),
rangeActive ? "T" : "F");
}
KeyRange keyRange(KeyRangeRef(rangeStart, rangeEnd));
auto allRanges = knownBlobRanges->intersectingRanges(keyRange);
for (auto& r : allRanges) {
if (r.value() != rangeActive) {
KeyRef overlapStart = (r.begin() > keyRange.begin) ? r.begin() : keyRange.begin;
KeyRef overlapEnd = (keyRange.end < r.end()) ? keyRange.end : r.end();
KeyRangeRef overlap(overlapStart, overlapEnd);
if (rangeActive) {
if (BM_DEBUG) {
printf("BM Adding client range [%s - %s)\n",
overlapStart.printable().c_str(),
overlapEnd.printable().c_str());
}
rangesToAdd->push_back_deep(ar, overlap);
} else {
if (BM_DEBUG) {
printf("BM Removing client range [%s - %s)\n",
overlapStart.printable().c_str(),
overlapEnd.printable().c_str());
}
rangesToRemove->push_back_deep(ar, overlap);
}
}
}
knownBlobRanges->insert(keyRange, rangeActive);
}
void updateClientBlobRanges(KeyRangeMap<bool>* knownBlobRanges,
RangeResult dbBlobRanges,
Arena& ar,
VectorRef<KeyRangeRef>* rangesToAdd,
VectorRef<KeyRangeRef>* rangesToRemove) {
if (BM_DEBUG) {
printf("Updating %d client blob ranges", dbBlobRanges.size() / 2);
for (int i = 0; i < dbBlobRanges.size() - 1; i += 2) {
printf(" [%s - %s)", dbBlobRanges[i].key.printable().c_str(), dbBlobRanges[i + 1].key.printable().c_str());
}
printf("\n");
}
// essentially do merge diff of current known blob ranges and new ranges, to assign new ranges to
// workers and revoke old ranges from workers
// basically, for any range that is set in results that isn't set in ranges, assign the range to the
// worker. for any range that isn't set in results that is set in ranges, revoke the range from the
// worker. and, update ranges to match results as you go
// FIXME: could change this to O(N) instead of O(NLogN) by doing a sorted merge instead of requesting the
// intersection for each insert, but this operation is pretty infrequent so it's probably not necessary
if (dbBlobRanges.size() == 0) {
// special case. Nothing in the DB, reset knownBlobRanges and revoke all existing ranges from workers
handleClientBlobRange(
knownBlobRanges, ar, rangesToAdd, rangesToRemove, normalKeys.begin, normalKeys.end, false);
} else {
if (dbBlobRanges[0].key > normalKeys.begin) {
handleClientBlobRange(
knownBlobRanges, ar, rangesToAdd, rangesToRemove, normalKeys.begin, dbBlobRanges[0].key, false);
}
for (int i = 0; i < dbBlobRanges.size() - 1; i++) {
if (dbBlobRanges[i].key >= normalKeys.end) {
if (BM_DEBUG) {
printf("Found invalid blob range start %s\n", dbBlobRanges[i].key.printable().c_str());
}
break;
}
bool active = dbBlobRanges[i].value == LiteralStringRef("1");
if (active) {
ASSERT(dbBlobRanges[i + 1].value == StringRef());
if (BM_DEBUG) {
printf("BM sees client range [%s - %s)\n",
dbBlobRanges[i].key.printable().c_str(),
dbBlobRanges[i + 1].key.printable().c_str());
}
}
KeyRef endKey = dbBlobRanges[i + 1].key;
if (endKey > normalKeys.end) {
if (BM_DEBUG) {
printf("Removing system keyspace from blob range [%s - %s)\n",
dbBlobRanges[i].key.printable().c_str(),
endKey.printable().c_str());
}
endKey = normalKeys.end;
}
handleClientBlobRange(
knownBlobRanges, ar, rangesToAdd, rangesToRemove, dbBlobRanges[i].key, endKey, active);
}
if (dbBlobRanges[dbBlobRanges.size() - 1].key < normalKeys.end) {
handleClientBlobRange(knownBlobRanges,
ar,
rangesToAdd,
rangesToRemove,
dbBlobRanges[dbBlobRanges.size() - 1].key,
normalKeys.end,
false);
}
}
knownBlobRanges->coalesce(normalKeys);
}
void getRanges(std::vector<std::pair<KeyRangeRef, bool>>& results, KeyRangeMap<bool>& knownBlobRanges) {
if (BM_DEBUG) {
printf("Getting ranges:\n");
}
auto allRanges = knownBlobRanges.ranges();
for (auto& r : allRanges) {
results.emplace_back(r.range(), r.value());
if (BM_DEBUG) {
printf(
" [%s - %s): %s\n", r.begin().printable().c_str(), r.end().printable().c_str(), r.value() ? "T" : "F");
}
}
}
struct RangeAssignmentData {
AssignRequestType type;
RangeAssignmentData() : type(AssignRequestType::Normal) {}
RangeAssignmentData(AssignRequestType type) : type(type) {}
};
struct RangeRevokeData {
bool dispose;
RangeRevokeData() {}
RangeRevokeData(bool dispose) : dispose(dispose) {}
};
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struct RangeAssignment {
bool isAssign;
KeyRange keyRange;
Optional<UID> worker;
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// I tried doing this with a union and it was just kind of messy
Optional<RangeAssignmentData> assign;
Optional<RangeRevokeData> revoke;
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};
// TODO: track worker's reads/writes eventually
struct BlobWorkerStats {
int numGranulesAssigned;
BlobWorkerStats(int numGranulesAssigned = 0) : numGranulesAssigned(numGranulesAssigned) {}
};
struct BlobManagerData {
UID id;
Database db;
Optional<Key> dcId;
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PromiseStream<Future<Void>> addActor;
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std::unordered_map<UID, BlobWorkerInterface> workersById;
std::unordered_map<UID, BlobWorkerStats> workerStats; // mapping between workerID -> workerStats
std::unordered_set<NetworkAddress> workerAddresses;
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std::unordered_set<UID> deadWorkers;
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KeyRangeMap<UID> workerAssignments;
KeyRangeMap<bool> knownBlobRanges;
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AsyncTrigger startRecruiting;
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Debouncer restartRecruiting;
std::set<NetworkAddress> recruitingLocalities; // the addrs of the workers being recruited on
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AsyncVar<int> recruitingStream;
int64_t epoch = -1;
int64_t seqNo = 1;
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Promise<Void> iAmReplaced;
// The order maintained here is important. The order ranges are put into the promise stream is the order they get
// assigned sequence numbers
PromiseStream<RangeAssignment> rangesToAssign;
BlobManagerData(UID id, Database db, Optional<Key> dcId)
: id(id), db(db), dcId(dcId), knownBlobRanges(false, normalKeys.end),
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restartRecruiting(SERVER_KNOBS->DEBOUNCE_RECRUITING_DELAY), recruitingStream(0) {}
~BlobManagerData() { printf("Destroying blob manager data for %s\n", id.toString().c_str()); }
};
ACTOR Future<Standalone<VectorRef<KeyRef>>> splitRange(Reference<ReadYourWritesTransaction> tr, KeyRange range) {
// TODO is it better to just pass empty metrics to estimated?
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// redo split if previous txn failed to calculate it
loop {
try {
if (BM_DEBUG) {
printf(
"Splitting new range [%s - %s)\n", range.begin.printable().c_str(), range.end.printable().c_str());
}
StorageMetrics estimated = wait(tr->getTransaction().getStorageMetrics(range, CLIENT_KNOBS->TOO_MANY));
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if (BM_DEBUG) {
fmt::print("Estimated bytes for [{0} - {1}): {2}\n",
range.begin.printable(),
range.end.printable(),
estimated.bytes);
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}
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if (estimated.bytes > SERVER_KNOBS->BG_SNAPSHOT_FILE_TARGET_BYTES) {
// printf(" Splitting range\n");
// only split on bytes
StorageMetrics splitMetrics;
splitMetrics.bytes = SERVER_KNOBS->BG_SNAPSHOT_FILE_TARGET_BYTES;
splitMetrics.bytesPerKSecond = splitMetrics.infinity;
splitMetrics.iosPerKSecond = splitMetrics.infinity;
splitMetrics.bytesReadPerKSecond = splitMetrics.infinity; // Don't split by readBandwidth
Standalone<VectorRef<KeyRef>> keys =
wait(tr->getTransaction().splitStorageMetrics(range, splitMetrics, estimated));
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ASSERT(keys.size() >= 2);
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return keys;
} else {
// printf(" Not splitting range\n");
Standalone<VectorRef<KeyRef>> keys;
keys.push_back_deep(keys.arena(), range.begin);
keys.push_back_deep(keys.arena(), range.end);
return keys;
}
} catch (Error& e) {
wait(tr->onError(e));
}
}
}
// Picks a worker with the fewest number of already assigned ranges.
// If there is a tie, picks one such worker at random.
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ACTOR Future<UID> pickWorkerForAssign(BlobManagerData* bmData) {
// wait until there are BWs to pick from
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while (bmData->workerStats.size() == 0) {
bmData->restartRecruiting.trigger();
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wait(bmData->recruitingStream.onChange());
}
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int minGranulesAssigned = INT_MAX;
std::vector<UID> eligibleWorkers;
for (auto const& worker : bmData->workerStats) {
UID currId = worker.first;
int granulesAssigned = worker.second.numGranulesAssigned;
if (granulesAssigned < minGranulesAssigned) {
eligibleWorkers.resize(0);
minGranulesAssigned = granulesAssigned;
eligibleWorkers.emplace_back(currId);
} else if (granulesAssigned == minGranulesAssigned) {
eligibleWorkers.emplace_back(currId);
}
}
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// pick a random worker out of the eligible workers
ASSERT(eligibleWorkers.size() > 0);
int idx = deterministicRandom()->randomInt(0, eligibleWorkers.size());
if (BM_DEBUG) {
printf("picked worker %s, which has a minimal number (%d) of granules assigned\n",
eligibleWorkers[idx].toString().c_str(),
minGranulesAssigned);
}
return eligibleWorkers[idx];
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}
ACTOR Future<Void> doRangeAssignment(BlobManagerData* bmData, RangeAssignment assignment, UID workerID, int64_t seqNo) {
if (BM_DEBUG) {
fmt::print("BM {0} {1} range [{2} - {3}) @ ({4}, {5})\n",
bmData->id.toString(),
assignment.isAssign ? "assigning" : "revoking",
assignment.keyRange.begin.printable(),
assignment.keyRange.end.printable(),
bmData->epoch,
seqNo);
}
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try {
state AssignBlobRangeReply rep;
if (assignment.isAssign) {
ASSERT(assignment.assign.present());
ASSERT(!assignment.revoke.present());
AssignBlobRangeRequest req;
req.keyRange = KeyRangeRef(StringRef(req.arena, assignment.keyRange.begin),
StringRef(req.arena, assignment.keyRange.end));
req.managerEpoch = bmData->epoch;
req.managerSeqno = seqNo;
req.type = assignment.assign.get().type;
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// if that worker isn't alive anymore, add the range back into the stream
if (bmData->workersById.count(workerID) == 0) {
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throw no_more_servers();
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}
AssignBlobRangeReply _rep = wait(bmData->workersById[workerID].assignBlobRangeRequest.getReply(req));
rep = _rep;
} else {
ASSERT(!assignment.assign.present());
ASSERT(assignment.revoke.present());
RevokeBlobRangeRequest req;
req.keyRange = KeyRangeRef(StringRef(req.arena, assignment.keyRange.begin),
StringRef(req.arena, assignment.keyRange.end));
req.managerEpoch = bmData->epoch;
req.managerSeqno = seqNo;
req.dispose = assignment.revoke.get().dispose;
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// if that worker isn't alive anymore, this is a noop
if (bmData->workersById.count(workerID)) {
AssignBlobRangeReply _rep = wait(bmData->workersById[workerID].revokeBlobRangeRequest.getReply(req));
rep = _rep;
} else {
return Void();
}
}
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if (!rep.epochOk) {
if (BM_DEBUG) {
printf("BM heard from BW that there is a new manager with higher epoch\n");
}
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if (bmData->iAmReplaced.canBeSet()) {
bmData->iAmReplaced.send(Void());
}
}
} catch (Error& e) {
if (e.code() == error_code_operation_cancelled) {
throw;
}
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// TODO confirm: using reliable delivery this should only trigger if the worker is marked as failed, right?
// So assignment needs to be retried elsewhere, and a revoke is trivially complete
if (assignment.isAssign) {
if (BM_DEBUG) {
printf("BM got error assigning range [%s - %s) to worker %s, requeueing\n",
assignment.keyRange.begin.printable().c_str(),
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assignment.keyRange.end.printable().c_str(),
workerID.toString().c_str());
}
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// re-send revoke to queue to handle range being un-assigned from that worker before the new one
RangeAssignment revokeOld;
revokeOld.isAssign = false;
revokeOld.worker = workerID;
revokeOld.keyRange = assignment.keyRange;
revokeOld.revoke = RangeRevokeData(false);
bmData->rangesToAssign.send(revokeOld);
// send assignment back to queue as is, clearing designated worker if present
assignment.worker.reset();
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bmData->rangesToAssign.send(assignment);
// FIXME: improvement would be to add history of failed workers to assignment so it can try other ones first
} else {
if (BM_DEBUG) {
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printf("BM got error revoking range [%s - %s) from worker",
assignment.keyRange.begin.printable().c_str(),
assignment.keyRange.end.printable().c_str());
}
if (assignment.revoke.get().dispose) {
if (BM_DEBUG) {
printf(", retrying for dispose\n");
}
// send assignment back to queue as is, clearing designated worker if present
assignment.worker.reset();
bmData->rangesToAssign.send(assignment);
//
} else {
if (BM_DEBUG) {
printf(", ignoring\n");
}
}
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}
}
return Void();
}
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ACTOR Future<Void> rangeAssigner(BlobManagerData* bmData) {
loop {
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// inject delay into range assignments
if (BUGGIFY_WITH_PROB(0.05)) {
wait(delay(deterministicRandom()->random01()));
}
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state RangeAssignment assignment = waitNext(bmData->rangesToAssign.getFuture());
state int64_t seqNo = bmData->seqNo;
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bmData->seqNo++;
// modify the in-memory assignment data structures, and send request off to worker
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state UID workerId;
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if (assignment.isAssign) {
// Ensure range isn't currently assigned anywhere, and there is only 1 intersecting range
auto currentAssignments = bmData->workerAssignments.intersectingRanges(assignment.keyRange);
int count = 0;
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for (auto i = currentAssignments.begin(); i != currentAssignments.end(); ++i) {
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/* TODO: rethink asserts here
if (assignment.assign.get().type == AssignRequestType::Continue) {
ASSERT(assignment.worker.present());
ASSERT(it.value() == assignment.worker.get());
} else {
ASSERT(it.value() == UID());
}
*/
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count++;
}
ASSERT(count == 1);
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if (assignment.worker.present() && assignment.worker.get().isValid()) {
workerId = assignment.worker.get();
} else {
if (BM_DEBUG) {
printf("About to pick worker for seqno %d in BM %s\n", seqNo, bmData->id.toString().c_str());
}
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UID _workerId = wait(pickWorkerForAssign(bmData));
if (BM_DEBUG) {
printf("Found worker BW %s for seqno %d\n", _workerId.toString().c_str(), seqNo);
}
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workerId = _workerId;
}
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bmData->workerAssignments.insert(assignment.keyRange, workerId);
// If we know about the worker and this is not a continue, then this is a new range for the worker
if (bmData->workerStats.count(workerId) && assignment.assign.get().type != AssignRequestType::Continue) {
bmData->workerStats[workerId].numGranulesAssigned += 1;
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}
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// FIXME: if range is assign, have some sort of semaphore for outstanding assignments so we don't assign
// a ton ranges at once and blow up FDB with reading initial snapshots.
bmData->addActor.send(doRangeAssignment(bmData, assignment, workerId, seqNo));
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} else {
// Revoking a range could be a large range that contains multiple ranges.
auto currentAssignments = bmData->workerAssignments.intersectingRanges(assignment.keyRange);
for (auto& it : currentAssignments) {
// ensure range doesn't truncate existing ranges
ASSERT(it.begin() >= assignment.keyRange.begin);
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ASSERT(it.end() <= assignment.keyRange.end);
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// It is fine for multiple disjoint sub-ranges to have the same sequence number since they were part of
// the same logical change
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if (bmData->workerStats.count(it.value())) {
bmData->workerStats[it.value()].numGranulesAssigned -= 1;
}
// revoke the range for the worker that owns it, not the worker specified in the revoke
bmData->addActor.send(doRangeAssignment(bmData, assignment, it.value(), seqNo));
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}
bmData->workerAssignments.insert(assignment.keyRange, UID());
}
}
}
ACTOR Future<Void> checkManagerLock(Reference<ReadYourWritesTransaction> tr, BlobManagerData* bmData) {
Optional<Value> currentLockValue = wait(tr->get(blobManagerEpochKey));
ASSERT(currentLockValue.present());
int64_t currentEpoch = decodeBlobManagerEpochValue(currentLockValue.get());
if (currentEpoch != bmData->epoch) {
ASSERT(currentEpoch > bmData->epoch);
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if (BM_DEBUG) {
fmt::print(
"BM {0} found new epoch {1} > {2} in lock check\n", bmData->id.toString(), currentEpoch, bmData->epoch);
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}
if (bmData->iAmReplaced.canBeSet()) {
bmData->iAmReplaced.send(Void());
}
throw granule_assignment_conflict();
}
tr->addReadConflictRange(singleKeyRange(blobManagerEpochKey));
return Void();
}
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// FIXME: this does all logic in one transaction. Adding a giant range to an existing database to blobify would
// require doing a ton of storage metrics calls, which we should split up across multiple transactions likely.
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ACTOR Future<Void> monitorClientRanges(BlobManagerData* bmData) {
loop {
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state Reference<ReadYourWritesTransaction> tr = makeReference<ReadYourWritesTransaction>(bmData->db);
if (BM_DEBUG) {
printf("Blob manager checking for range updates\n");
}
loop {
try {
tr->setOption(FDBTransactionOptions::ACCESS_SYSTEM_KEYS);
tr->setOption(FDBTransactionOptions::PRIORITY_SYSTEM_IMMEDIATE);
// TODO probably knobs here? This should always be pretty small though
RangeResult results = wait(krmGetRanges(
tr, blobRangeKeys.begin, KeyRange(normalKeys), 10000, GetRangeLimits::BYTE_LIMIT_UNLIMITED));
ASSERT(!results.more && results.size() < CLIENT_KNOBS->TOO_MANY);
state Arena ar;
ar.dependsOn(results.arena());
VectorRef<KeyRangeRef> rangesToAdd;
VectorRef<KeyRangeRef> rangesToRemove;
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updateClientBlobRanges(&bmData->knownBlobRanges, results, ar, &rangesToAdd, &rangesToRemove);
for (KeyRangeRef range : rangesToRemove) {
if (BM_DEBUG) {
printf("BM Got range to revoke [%s - %s)\n",
range.begin.printable().c_str(),
range.end.printable().c_str());
}
RangeAssignment ra;
ra.isAssign = false;
ra.keyRange = range;
ra.revoke = RangeRevokeData(true); // dispose=true
bmData->rangesToAssign.send(ra);
}
state std::vector<Future<Standalone<VectorRef<KeyRef>>>> splitFutures;
// Divide new ranges up into equal chunks by using SS byte sample
for (KeyRangeRef range : rangesToAdd) {
splitFutures.push_back(splitRange(tr, range));
}
for (auto f : splitFutures) {
Standalone<VectorRef<KeyRef>> splits = wait(f);
if (BM_DEBUG) {
printf("Split client range [%s - %s) into %d ranges:\n",
splits[0].printable().c_str(),
splits[splits.size() - 1].printable().c_str(),
splits.size() - 1);
}
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for (int i = 0; i < splits.size() - 1; i++) {
KeyRange range = KeyRange(KeyRangeRef(splits[i], splits[i + 1]));
// only add the client range if this is the first BM or it's not already assigned
if (bmData->epoch == 1 || bmData->workerAssignments.intersectingRanges(range).empty()) {
if (BM_DEBUG) {
printf(
" [%s - %s)\n", range.begin.printable().c_str(), range.end.printable().c_str());
}
RangeAssignment ra;
ra.isAssign = true;
ra.keyRange = range;
ra.assign = RangeAssignmentData(); // type=normal
bmData->rangesToAssign.send(ra);
}
}
}
state Future<Void> watchFuture = tr->watch(blobRangeChangeKey);
wait(tr->commit());
if (BM_DEBUG) {
printf("Blob manager done processing client ranges, awaiting update\n");
}
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wait(watchFuture);
break;
} catch (Error& e) {
if (BM_DEBUG) {
printf("Blob manager got error looking for range updates %s\n", e.name());
}
wait(tr->onError(e));
}
}
}
}
ACTOR Future<Void> maybeSplitRange(BlobManagerData* bmData,
UID currentWorkerId,
KeyRange granuleRange,
UID granuleID,
Version granuleStartVersion,
Version latestVersion) {
state Reference<ReadYourWritesTransaction> tr = makeReference<ReadYourWritesTransaction>(bmData->db);
state Standalone<VectorRef<KeyRef>> newRanges;
state int64_t newLockSeqno = -1;
// first get ranges to split
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Standalone<VectorRef<KeyRef>> _newRanges = wait(splitRange(tr, granuleRange));
newRanges = _newRanges;
if (newRanges.size() == 2) {
// not large enough to split, just reassign back to worker
if (BM_DEBUG) {
printf("Not splitting existing range [%s - %s). Continuing assignment to %s\n",
granuleRange.begin.printable().c_str(),
granuleRange.end.printable().c_str(),
currentWorkerId.toString().c_str());
}
RangeAssignment raContinue;
raContinue.isAssign = true;
raContinue.worker = currentWorkerId;
raContinue.keyRange = granuleRange;
raContinue.assign = RangeAssignmentData(AssignRequestType::Continue); // continue assignment and re-snapshot
bmData->rangesToAssign.send(raContinue);
return Void();
}
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if (BM_DEBUG) {
printf("Splitting range [%s - %s) into (%d):\n",
granuleRange.begin.printable().c_str(),
granuleRange.end.printable().c_str(),
newRanges.size() - 1);
for (int i = 0; i < newRanges.size(); i++) {
printf(" %s\n", newRanges[i].printable().c_str());
}
}
// Need to split range. Persist intent to split and split metadata to DB BEFORE sending split requests
loop {
try {
tr->reset();
tr->setOption(FDBTransactionOptions::Option::PRIORITY_SYSTEM_IMMEDIATE);
tr->setOption(FDBTransactionOptions::Option::ACCESS_SYSTEM_KEYS);
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ASSERT(newRanges.size() > 2);
// make sure we're still manager when this transaction gets committed
wait(checkManagerLock(tr, bmData));
// acquire lock for old granule to make sure nobody else modifies it
state Key lockKey = blobGranuleLockKeyFor(granuleRange);
Optional<Value> lockValue = wait(tr->get(lockKey));
ASSERT(lockValue.present());
std::tuple<int64_t, int64_t, UID> prevGranuleLock = decodeBlobGranuleLockValue(lockValue.get());
if (std::get<0>(prevGranuleLock) > bmData->epoch) {
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if (BM_DEBUG) {
fmt::print("BM {0} found a higher epoch {1} than {2} for granule lock of [{3} - {4})\n",
bmData->id.toString(),
std::get<0>(prevGranuleLock),
bmData->epoch,
granuleRange.begin.printable(),
granuleRange.end.printable());
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}
if (bmData->iAmReplaced.canBeSet()) {
bmData->iAmReplaced.send(Void());
}
return Void();
}
if (newLockSeqno == -1) {
newLockSeqno = bmData->seqNo;
bmData->seqNo++;
ASSERT(newLockSeqno > std::get<1>(prevGranuleLock));
} else {
// previous transaction could have succeeded but got commit_unknown_result
ASSERT(newLockSeqno >= std::get<1>(prevGranuleLock));
}
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// acquire granule lock so nobody else can make changes to this granule.
tr->set(lockKey, blobGranuleLockValueFor(bmData->epoch, newLockSeqno, std::get<2>(prevGranuleLock)));
// set up split metadata
for (int i = 0; i < newRanges.size() - 1; i++) {
UID newGranuleID = deterministicRandom()->randomUniqueID();
Key splitKey = blobGranuleSplitKeyFor(granuleID, newGranuleID);
tr->atomicOp(splitKey,
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blobGranuleSplitValueFor(BlobGranuleSplitState::Initialized),
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MutationRef::SetVersionstampedValue);
Key historyKey = blobGranuleHistoryKeyFor(KeyRangeRef(newRanges[i], newRanges[i + 1]), latestVersion);
Standalone<BlobGranuleHistoryValue> historyValue;
historyValue.granuleID = newGranuleID;
historyValue.parentGranules.push_back(historyValue.arena(),
std::pair(granuleRange, granuleStartVersion));
/*printf("Creating history entry [%s - %s) - [%lld - %lld)\n",
newRanges[i].printable().c_str(),
newRanges[i + 1].printable().c_str(),
granuleStartVersion,
latestVersion);*/
tr->set(historyKey, blobGranuleHistoryValueFor(historyValue));
}
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wait(tr->commit());
break;
} catch (Error& e) {
if (e.code() == error_code_granule_assignment_conflict) {
if (bmData->iAmReplaced.canBeSet()) {
bmData->iAmReplaced.send(Void());
}
return Void();
}
wait(tr->onError(e));
}
}
// transaction committed, send range assignments
// revoke from current worker
RangeAssignment raRevoke;
raRevoke.isAssign = false;
raRevoke.worker = currentWorkerId;
raRevoke.keyRange = granuleRange;
raRevoke.revoke = RangeRevokeData(false); // not a dispose
bmData->rangesToAssign.send(raRevoke);
for (int i = 0; i < newRanges.size() - 1; i++) {
// reassign new range and do handover of previous range
RangeAssignment raAssignSplit;
raAssignSplit.isAssign = true;
raAssignSplit.keyRange = KeyRangeRef(newRanges[i], newRanges[i + 1]);
raAssignSplit.assign = RangeAssignmentData();
// don't care who this range gets assigned to
bmData->rangesToAssign.send(raAssignSplit);
}
return Void();
}
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ACTOR Future<Void> deregisterBlobWorker(BlobManagerData* bmData, BlobWorkerInterface interf) {
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state Reference<ReadYourWritesTransaction> tr = makeReference<ReadYourWritesTransaction>(bmData->db);
loop {
tr->setOption(FDBTransactionOptions::ACCESS_SYSTEM_KEYS);
tr->setOption(FDBTransactionOptions::PRIORITY_SYSTEM_IMMEDIATE);
try {
Key blobWorkerListKey = blobWorkerListKeyFor(interf.id());
tr->addReadConflictRange(singleKeyRange(blobWorkerListKey));
tr->clear(blobWorkerListKey);
wait(tr->commit());
if (BM_DEBUG) {
printf("Deregistered blob worker %s\n", interf.id().toString().c_str());
}
return Void();
} catch (Error& e) {
if (BM_DEBUG) {
printf("Deregistering blob worker %s got error %s\n", interf.id().toString().c_str(), e.name());
}
wait(tr->onError(e));
}
}
}
ACTOR Future<Void> killBlobWorker(BlobManagerData* bmData, BlobWorkerInterface bwInterf, bool registered) {
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state UID bwId = bwInterf.id();
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// Remove blob worker from stats map so that when we try to find a worker to takeover the range,
// the one we just killed isn't considered.
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// Remove it from workersById also since otherwise that worker addr will remain excluded
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// when we try to recruit new blob workers.
if (registered) {
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bmData->deadWorkers.insert(bwId);
bmData->workerStats.erase(bwId);
bmData->workersById.erase(bwId);
bmData->workerAddresses.erase(bwInterf.stableAddress());
}
// Remove blob worker from persisted list of blob workers
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Future<Void> deregister = deregisterBlobWorker(bmData, bwInterf);
// restart recruiting to replace the dead blob worker
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bmData->restartRecruiting.trigger();
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// for every range owned by this blob worker, we want to
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// - send a revoke request for that range
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// - add the range back to the stream of ranges to be assigned
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if (BM_DEBUG) {
printf("Taking back ranges from BW %s\n", bwId.toString().c_str());
}
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// copy ranges into vector before sending, because send then modifies workerAssignments
state std::vector<KeyRange> rangesToMove;
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for (auto& it : bmData->workerAssignments.ranges()) {
if (it.cvalue() == bwId) {
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rangesToMove.push_back(it.range());
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}
}
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for (auto& it : rangesToMove) {
// Send revoke request
RangeAssignment raRevoke;
raRevoke.isAssign = false;
raRevoke.keyRange = it;
raRevoke.revoke = RangeRevokeData(false);
bmData->rangesToAssign.send(raRevoke);
// Add range back into the stream of ranges to be assigned
RangeAssignment raAssign;
raAssign.isAssign = true;
raAssign.worker = Optional<UID>();
raAssign.keyRange = it;
raAssign.assign = RangeAssignmentData(); // not a continue
bmData->rangesToAssign.send(raAssign);
}
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// Send halt to blob worker, with no expectation of hearing back
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if (BM_DEBUG) {
printf("Sending halt to BW %s\n", bwId.toString().c_str());
}
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bmData->addActor.send(
brokenPromiseToNever(bwInterf.haltBlobWorker.getReply(HaltBlobWorkerRequest(bmData->epoch, bmData->id))));
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wait(deregister);
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if (registered) {
bmData->deadWorkers.erase(bwId);
}
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return Void();
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}
ACTOR Future<Void> monitorBlobWorkerStatus(BlobManagerData* bmData, BlobWorkerInterface bwInterf) {
state KeyRangeMap<std::pair<int64_t, int64_t>> lastSeenSeqno;
// outer loop handles reconstructing stream if it got a retryable error
loop {
try {
state ReplyPromiseStream<GranuleStatusReply> statusStream =
bwInterf.granuleStatusStreamRequest.getReplyStream(GranuleStatusStreamRequest(bmData->epoch));
// read from stream until worker fails (should never get explicit end_of_stream)
loop {
GranuleStatusReply rep = waitNext(statusStream.getFuture());
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if (BM_DEBUG) {
fmt::print("BM {0} got status of [{1} - {2}) @ ({3}, {4}) from BW {5}: {6}\n",
bmData->epoch,
rep.granuleRange.begin.printable(),
rep.granuleRange.end.printable(),
rep.epoch,
rep.seqno,
bwInterf.id().toString(),
rep.doSplit ? "split" : "");
}
if (rep.epoch > bmData->epoch) {
if (BM_DEBUG) {
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printf("BM heard from BW %s that there is a new manager with higher epoch\n",
bwInterf.id().toString().c_str());
}
if (bmData->iAmReplaced.canBeSet()) {
bmData->iAmReplaced.send(Void());
}
} else if (rep.epoch < bmData->epoch) {
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// TODO: revoke the range from that worker? and send optimistic halt req to other (zombie) BM?
// it's optimistic because such a BM is not necessarily a zombie. it could have gotten killed
// properly but the BW that sent this reply was behind (i.e. it started the req when the old BM
// was in charge and finished by the time the new BM took over)
continue;
}
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// TODO maybe this won't be true eventually, but right now the only time the blob worker reports
// back is to split the range.
ASSERT(rep.doSplit);
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// only evaluate for split if this worker currently owns the granule in this blob manager's mapping
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auto currGranuleAssignment = bmData->workerAssignments.rangeContaining(rep.granuleRange.begin);
if (!(currGranuleAssignment.begin() == rep.granuleRange.begin &&
currGranuleAssignment.end() == rep.granuleRange.end &&
currGranuleAssignment.cvalue() == bwInterf.id())) {
continue;
}
auto lastReqForGranule = lastSeenSeqno.rangeContaining(rep.granuleRange.begin);
if (rep.granuleRange.begin == lastReqForGranule.begin() &&
rep.granuleRange.end == lastReqForGranule.end() && rep.epoch == lastReqForGranule.value().first &&
rep.seqno == lastReqForGranule.value().second) {
if (BM_DEBUG) {
fmt::print("Manager {0} received repeat status for the same granule [{1} - {2}), ignoring.",
bmData->epoch,
rep.granuleRange.begin.printable(),
rep.granuleRange.end.printable());
}
} else {
if (BM_DEBUG) {
fmt::print("Manager {0} evaluating [{1} - {2}) for split\n",
bmData->epoch,
rep.granuleRange.begin.printable().c_str(),
rep.granuleRange.end.printable().c_str());
}
lastSeenSeqno.insert(rep.granuleRange, std::pair(rep.epoch, rep.seqno));
bmData->addActor.send(maybeSplitRange(
bmData, bwInterf.id(), rep.granuleRange, rep.granuleID, rep.startVersion, rep.latestVersion));
}
}
} catch (Error& e) {
if (e.code() == error_code_operation_cancelled) {
throw e;
}
// TODO: figure out why waitFailure in monitorBlobWorker doesn't pick up the connection failure first
if (e.code() == error_code_connection_failed || e.code() == error_code_broken_promise) {
throw e;
}
// if we got an error constructing or reading from stream that is retryable, wait and retry.
ASSERT(e.code() != error_code_end_of_stream);
if (e.code() == error_code_request_maybe_delivered) {
wait(delay(FLOW_KNOBS->PREVENT_FAST_SPIN_DELAY));
continue;
} else {
if (BM_DEBUG) {
printf("BM got unexpected error %s monitoring BW %s status\n",
e.name(),
bwInterf.id().toString().c_str());
}
// TODO change back from SevError?
TraceEvent(SevError, "BWStatusMonitoringFailed", bmData->id)
.detail("BlobWorkerID", bwInterf.id())
.error(e);
throw e;
}
}
}
}
ACTOR Future<Void> monitorBlobWorker(BlobManagerData* bmData, BlobWorkerInterface bwInterf) {
try {
state Future<Void> waitFailure = waitFailureClient(bwInterf.waitFailure, SERVER_KNOBS->BLOB_WORKER_TIMEOUT);
state Future<Void> monitorStatus = monitorBlobWorkerStatus(bmData, bwInterf);
choose {
when(wait(waitFailure)) {
if (BM_DEBUG) {
fmt::print("BM {0} detected BW {1} is dead\n", bmData->epoch, bwInterf.id().toString());
}
TraceEvent("BlobWorkerFailed", bmData->id).detail("BlobWorkerID", bwInterf.id());
}
when(wait(monitorStatus)) {
ASSERT(false);
throw internal_error();
}
}
} catch (Error& e) {
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// will blob worker get cleaned up in this case?
if (e.code() == error_code_operation_cancelled) {
throw e;
}
// TODO: re-evaluate the expected errors here once wait failure issue is resolved
// Expected errors here are: [connection_failed, broken_promise]
if (e.code() != error_code_connection_failed && e.code() != error_code_broken_promise) {
if (BM_DEBUG) {
printf("BM got unexpected error %s monitoring BW %s\n", e.name(), bwInterf.id().toString().c_str());
}
// TODO change back from SevError?
TraceEvent(SevError, "BWMonitoringFailed", bmData->id).detail("BlobWorkerID", bwInterf.id()).error(e);
throw e;
}
}
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// kill the blob worker
wait(killBlobWorker(bmData, bwInterf, true));
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if (BM_DEBUG) {
printf("No longer monitoring BW %s\n", bwInterf.id().toString().c_str());
}
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return Void();
}
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ACTOR Future<Void> checkBlobWorkerList(BlobManagerData* bmData, Promise<Void> workerListReady) {
loop {
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// Get list of last known blob workers
// note: the list will include every blob worker that the old manager knew about,
// but it might also contain blob workers that died while the new manager was being recruited
std::vector<BlobWorkerInterface> blobWorkers = wait(getBlobWorkers(bmData->db));
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// add all blob workers to this new blob manager's records and start monitoring it
for (auto& worker : blobWorkers) {
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if (!bmData->deadWorkers.count(worker.id())) {
if (!bmData->workerAddresses.count(worker.stableAddress()) && worker.locality.dcId() == bmData->dcId) {
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bmData->workerAddresses.insert(worker.stableAddress());
bmData->workersById[worker.id()] = worker;
bmData->workerStats[worker.id()] = BlobWorkerStats();
bmData->addActor.send(monitorBlobWorker(bmData, worker));
} else if (!bmData->workersById.count(worker.id())) {
bmData->addActor.send(killBlobWorker(bmData, worker, false));
}
}
}
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if (workerListReady.canBeSet()) {
workerListReady.send(Void());
}
wait(delay(SERVER_KNOBS->BLOB_WORKERLIST_FETCH_INTERVAL));
}
}
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ACTOR Future<Void> recoverBlobManager(BlobManagerData* bmData) {
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state Promise<Void> workerListReady;
bmData->addActor.send(checkBlobWorkerList(bmData, workerListReady));
wait(workerListReady.getFuture());
// Once we acknowledge the existing blob workers, we can go ahead and recruit new ones
bmData->startRecruiting.trigger();
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// skip them rest of the algorithm for the first blob manager
if (bmData->epoch == 1) {
return Void();
}
// At this point, bmData->workersById is a list of all alive blob workers, but could also include some dead BWs.
// The algorithm below works as follows:
// 1. We get the existing granule mappings that were persisted by blob workers who were assigned ranges and
// add them to bmData->granuleAssignments, which is a key range map.
// Details: re-assignments might have happened between the time the mapping was last updated and now.
// For example, suppose a blob manager sends requests to the range assigner stream to move a granule G.
// However, before sending those requests off to the workers, the BM dies. So the persisting mapping
// still has G->oldWorker. The following algorithm will re-assign G to oldWorker (as long as it is also still
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// alive). Note that this is fine because it simply means that the range was not moved optimally, but it is
// still owned. In the above case, even if the revoke goes through, since we don't update the mapping during
// revokes, this is the same as the case above. Another case to consider is when a blob worker dies when the
// BM is recovering. Now the mapping at this time looks like G->deadBW. But the rangeAssigner handles this:
// we'll try to assign a range to a dead worker and fail and reassign it to the next best worker.
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//
// 2. We get the existing split intentions that were Started but not acknowledged by any blob workers and
// add them to our key range map, bmData->granuleAssignments. Note that we are adding them on top of
// the granule mappings and since we are using a key range map, we end up with the same set of shard
// boundaries as the old blob manager had. For these splits, we simply assign the range to the next
// best worker. This is not any worst than what the old blob manager would have done.
// Details: Note that this means that if a worker we intended to give a splitted range to dies
// before the new BM recovers, then we'll simply assign the range to the next best worker.
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//
// 3. For every range in our granuleAssignments, we send an assign request to the stream of requests,
// ultimately giving every range back to some worker (trying to mimic the state of the old BM).
// If the worker already had the range, this is a no-op. If the worker didn't have it, it will
// begin persisting it. The worker that had the same range before will now be at a lower seqno.
state KeyRangeMap<Optional<UID>> workerAssignments;
state Reference<ReadYourWritesTransaction> tr = makeReference<ReadYourWritesTransaction>(bmData->db);
// Step 1. Get the latest known mapping of granules to blob workers (i.e. assignments)
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state KeyRef beginKey = normalKeys.begin;
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loop {
try {
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tr->setOption(FDBTransactionOptions::ACCESS_SYSTEM_KEYS);
tr->setOption(FDBTransactionOptions::PRIORITY_SYSTEM_IMMEDIATE);
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wait(checkManagerLock(tr, bmData));
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// TODO: replace row limit with knob
KeyRange nextRange(KeyRangeRef(beginKey, normalKeys.end));
RangeResult results = wait(
krmGetRanges(tr, blobGranuleMappingKeys.begin, nextRange, 10000, GetRangeLimits::BYTE_LIMIT_UNLIMITED));
// Add the mappings to our in memory key range map
for (int rangeIdx = 0; rangeIdx < results.size() - 1; rangeIdx++) {
Key granuleStartKey = results[rangeIdx].key;
Key granuleEndKey = results[rangeIdx + 1].key;
if (results[rangeIdx].value.size()) {
// note: if the old owner is dead, we handle this in rangeAssigner
UID existingOwner = decodeBlobGranuleMappingValue(results[rangeIdx].value);
workerAssignments.insert(KeyRangeRef(granuleStartKey, granuleEndKey), existingOwner);
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}
}
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if (!results.more) {
break;
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}
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beginKey = results.readThrough.get();
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} catch (Error& e) {
wait(tr->onError(e));
}
}
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// Step 2. Get the latest known split intentions
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tr->reset();
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beginKey = blobGranuleSplitKeys.begin;
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loop {
try {
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tr->setOption(FDBTransactionOptions::ACCESS_SYSTEM_KEYS);
tr->setOption(FDBTransactionOptions::PRIORITY_SYSTEM_IMMEDIATE);
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wait(checkManagerLock(tr, bmData));
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// TODO: replace row limit with knob
RangeResult results = wait(tr->getRange(KeyRangeRef(beginKey, blobGranuleSplitKeys.end), 10000));
// Add the granules for the started split intentions to the in-memory key range map
for (auto split : results) {
UID parentGranuleID, granuleID;
BlobGranuleSplitState splitState;
Version version;
if (split.expectedSize() == 0) {
continue;
}
std::tie(parentGranuleID, granuleID) = decodeBlobGranuleSplitKey(split.key);
std::tie(splitState, version) = decodeBlobGranuleSplitValue(split.value);
const KeyRange range = blobGranuleSplitKeyRangeFor(parentGranuleID);
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if (splitState <= BlobGranuleSplitState::Initialized) {
// the empty UID signifies that we need to find an owner (worker) for this range
workerAssignments.insert(range, UID());
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}
}
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if (!results.more) {
break;
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}
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beginKey = results.readThrough.get();
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} catch (Error& e) {
wait(tr->onError(e));
}
}
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// Step 3. Send assign requests for all the granules and transfer assignments
// from local workerAssignments to bmData
for (auto& range : workerAssignments.intersectingRanges(normalKeys)) {
if (!range.value().present()) {
continue;
}
bmData->workerAssignments.insert(range.range(), range.value().get());
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RangeAssignment raAssign;
raAssign.isAssign = true;
raAssign.worker = range.value().get();
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raAssign.keyRange = range.range();
raAssign.assign = RangeAssignmentData(AssignRequestType::Reassign);
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bmData->rangesToAssign.send(raAssign);
}
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return Void();
}
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ACTOR Future<Void> chaosRangeMover(BlobManagerData* bmData) {
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ASSERT(g_network->isSimulated());
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loop {
wait(delay(30.0));
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if (g_simulator.speedUpSimulation) {
if (BM_DEBUG) {
printf("Range mover stopping\n");
}
return Void();
}
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if (bmData->workersById.size() > 1) {
int tries = 10;
while (tries > 0) {
tries--;
auto randomRange = bmData->workerAssignments.randomRange();
if (randomRange.value() != UID()) {
if (BM_DEBUG) {
printf("Range mover moving range [%s - %s): %s\n",
randomRange.begin().printable().c_str(),
randomRange.end().printable().c_str(),
randomRange.value().toString().c_str());
}
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// FIXME: with low probability, could immediately revoke it from the new assignment and move
// it back right after to test that race
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state KeyRange range = randomRange.range();
RangeAssignment revokeOld;
revokeOld.isAssign = false;
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revokeOld.keyRange = range;
revokeOld.revoke = RangeRevokeData(false);
bmData->rangesToAssign.send(revokeOld);
RangeAssignment assignNew;
assignNew.isAssign = true;
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assignNew.keyRange = range;
assignNew.assign = RangeAssignmentData(); // not a continue
bmData->rangesToAssign.send(assignNew);
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break;
}
}
if (tries == 0 && BM_DEBUG) {
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printf("Range mover couldn't find random range to move, skipping\n");
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}
} else if (BM_DEBUG) {
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printf("Range mover found %d workers, skipping\n", bmData->workerAssignments.size());
}
}
}
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// Returns the number of blob workers on addr
int numExistingBWOnAddr(BlobManagerData* self, const AddressExclusion& addr) {
int numExistingBW = 0;
for (auto& server : self->workersById) {
const NetworkAddress& netAddr = server.second.stableAddress();
AddressExclusion usedAddr(netAddr.ip, netAddr.port);
if (usedAddr == addr) {
++numExistingBW;
}
}
return numExistingBW;
}
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// Tries to recruit a blob worker on the candidateWorker process
ACTOR Future<Void> initializeBlobWorker(BlobManagerData* self, RecruitBlobWorkerReply candidateWorker) {
const NetworkAddress& netAddr = candidateWorker.worker.stableAddress();
AddressExclusion workerAddr(netAddr.ip, netAddr.port);
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self->recruitingStream.set(self->recruitingStream.get() + 1);
// Ask the candidateWorker to initialize a BW only if the worker does not have a pending request
if (numExistingBWOnAddr(self, workerAddr) == 0 &&
self->recruitingLocalities.count(candidateWorker.worker.stableAddress()) == 0) {
state UID interfaceId = deterministicRandom()->randomUniqueID();
state InitializeBlobWorkerRequest initReq;
initReq.reqId = deterministicRandom()->randomUniqueID();
initReq.interfaceId = interfaceId;
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// acknowledge that this worker is currently being recruited on
self->recruitingLocalities.insert(candidateWorker.worker.stableAddress());
TraceEvent("BMRecruiting")
.detail("State", "Sending request to worker")
.detail("WorkerID", candidateWorker.worker.id())
.detail("WorkerLocality", candidateWorker.worker.locality.toString())
.detail("Interf", interfaceId)
.detail("Addr", candidateWorker.worker.address());
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// send initialization request to worker (i.e. worker.actor.cpp)
// here, the worker will construct the blob worker at which point the BW will start!
Future<ErrorOr<InitializeBlobWorkerReply>> fRecruit =
candidateWorker.worker.blobWorker.tryGetReply(initReq, TaskPriority::BlobManager);
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// wait on the reply to the request
state ErrorOr<InitializeBlobWorkerReply> newBlobWorker = wait(fRecruit);
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// if the initialization failed in an unexpected way, then kill the BM.
// if it failed in an expected way, add some delay before we try to recruit again
// on this worker
if (newBlobWorker.isError()) {
TraceEvent(SevWarn, "BMRecruitmentError").error(newBlobWorker.getError());
if (!newBlobWorker.isError(error_code_recruitment_failed) &&
!newBlobWorker.isError(error_code_request_maybe_delivered)) {
throw newBlobWorker.getError();
}
wait(delay(SERVER_KNOBS->STORAGE_RECRUITMENT_DELAY, TaskPriority::BlobManager));
}
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// if the initialization succeeded, add the blob worker's interface to
// the blob manager's data and start monitoring the blob worker
if (newBlobWorker.present()) {
BlobWorkerInterface bwi = newBlobWorker.get().interf;
if (!self->deadWorkers.count(bwi.id())) {
if (!self->workerAddresses.count(bwi.stableAddress()) && bwi.locality.dcId() == self->dcId) {
self->workerAddresses.insert(bwi.stableAddress());
self->workersById[bwi.id()] = bwi;
self->workerStats[bwi.id()] = BlobWorkerStats();
self->addActor.send(monitorBlobWorker(self, bwi));
} else if (!self->workersById.count(bwi.id())) {
self->addActor.send(killBlobWorker(self, bwi, false));
}
}
TraceEvent("BMRecruiting")
.detail("State", "Finished request")
.detail("WorkerID", candidateWorker.worker.id())
.detail("WorkerLocality", candidateWorker.worker.locality.toString())
.detail("Interf", interfaceId)
.detail("Addr", candidateWorker.worker.address());
}
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// acknowledge that this worker is not actively being recruited on anymore.
// if the initialization did succeed, then this worker will still be excluded
// since it was added to workersById.
self->recruitingLocalities.erase(candidateWorker.worker.stableAddress());
}
// try to recruit more blob workers
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self->recruitingStream.set(self->recruitingStream.get() - 1);
self->restartRecruiting.trigger();
return Void();
}
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// Recruits blob workers in a loop
ACTOR Future<Void> blobWorkerRecruiter(
BlobManagerData* self,
Reference<IAsyncListener<RequestStream<RecruitBlobWorkerRequest>>> recruitBlobWorker) {
state Future<RecruitBlobWorkerReply> fCandidateWorker;
state RecruitBlobWorkerRequest lastRequest;
// wait until existing blob workers have been acknowledged so we don't break recruitment invariants
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loop choose {
when(wait(self->startRecruiting.onTrigger())) { break; }
}
loop {
try {
state RecruitBlobWorkerRequest recruitReq;
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// workers that are used by existing blob workers should be excluded
for (auto const& [bwId, bwInterf] : self->workersById) {
auto addr = bwInterf.stableAddress();
AddressExclusion addrExcl(addr.ip, addr.port);
recruitReq.excludeAddresses.emplace_back(addrExcl);
}
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// workers that are used by blob workers that are currently being recruited should be excluded
for (auto addr : self->recruitingLocalities) {
recruitReq.excludeAddresses.emplace_back(AddressExclusion(addr.ip, addr.port));
}
TraceEvent("BMRecruiting").detail("State", "Sending request to CC");
if (!fCandidateWorker.isValid() || fCandidateWorker.isReady() ||
recruitReq.excludeAddresses != lastRequest.excludeAddresses) {
lastRequest = recruitReq;
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// send req to cluster controller to get back a candidate worker we can recruit on
fCandidateWorker =
brokenPromiseToNever(recruitBlobWorker->get().getReply(recruitReq, TaskPriority::BlobManager));
}
choose {
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// when we get back a worker we can use, we will try to initialize a blob worker onto that
// process
when(RecruitBlobWorkerReply candidateWorker = wait(fCandidateWorker)) {
self->addActor.send(initializeBlobWorker(self, candidateWorker));
}
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// when the CC changes, so does the request stream so we need to restart recruiting here
when(wait(recruitBlobWorker->onChange())) { fCandidateWorker = Future<RecruitBlobWorkerReply>(); }
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// signal used to restart the loop and try to recruit the next blob worker
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when(wait(self->restartRecruiting.onTrigger())) {}
}
wait(delay(FLOW_KNOBS->PREVENT_FAST_SPIN_DELAY, TaskPriority::BlobManager));
} catch (Error& e) {
if (e.code() != error_code_timed_out) {
throw;
}
TEST(true); // Blob worker recruitment timed out
}
}
}
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ACTOR Future<Void> blobManager(BlobManagerInterface bmInterf,
Reference<AsyncVar<ServerDBInfo> const> dbInfo,
int64_t epoch) {
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state BlobManagerData self(deterministicRandom()->randomUniqueID(),
openDBOnServer(dbInfo, TaskPriority::DefaultEndpoint, LockAware::True),
bmInterf.locality.dcId());
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state Future<Void> collection = actorCollection(self.addActor.getFuture());
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if (BM_DEBUG) {
printf("Blob manager starting...\n");
}
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self.epoch = epoch;
// make sure the epoch hasn't gotten stale
state Reference<ReadYourWritesTransaction> tr = makeReference<ReadYourWritesTransaction>(self.db);
tr->setOption(FDBTransactionOptions::ACCESS_SYSTEM_KEYS);
tr->setOption(FDBTransactionOptions::PRIORITY_SYSTEM_IMMEDIATE);
try {
wait(checkManagerLock(tr, &self));
} catch (Error& e) {
if (BM_DEBUG) {
printf("Blob manager lock check got unexpected error %s. Dying...\n", e.name());
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}
return Void();
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}
if (BM_DEBUG) {
fmt::print("Blob manager acquired lock at epoch {}\n", epoch);
}
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// although we start the recruiter, we wait until existing workers are ack'd
auto recruitBlobWorker = IAsyncListener<RequestStream<RecruitBlobWorkerRequest>>::create(
dbInfo, [](auto const& info) { return info.clusterInterface.recruitBlobWorker; });
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self.addActor.send(blobWorkerRecruiter(&self, recruitBlobWorker));
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// we need to recover the old blob manager's state (e.g. granule assignments) before
// before the new blob manager does anything
wait(recoverBlobManager(&self));
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self.addActor.send(monitorClientRanges(&self));
self.addActor.send(rangeAssigner(&self));
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if (BUGGIFY) {
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self.addActor.send(chaosRangeMover(&self));
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}
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// TODO probably other things here eventually
try {
loop choose {
when(wait(self.iAmReplaced.getFuture())) {
if (BM_DEBUG) {
printf("Blob Manager exiting because it is replaced\n");
}
break;
}
when(HaltBlobManagerRequest req = waitNext(bmInterf.haltBlobManager.getFuture())) {
req.reply.send(Void());
TraceEvent("BlobManagerHalted", bmInterf.id()).detail("ReqID", req.requesterID);
break;
}
when(wait(collection)) {
TraceEvent("BlobManagerActorCollectionError");
ASSERT(false);
throw internal_error();
}
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}
} catch (Error& err) {
TraceEvent("BlobManagerDied", bmInterf.id()).error(err, true);
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}
return Void();
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}
// Test:
// start empty
// DB has [A - B). That should show up in knownBlobRanges and should be in added
// DB has nothing. knownBlobRanges should be empty and [A - B) should be in removed
// DB has [A - B) and [C - D). They should both show up in knownBlobRanges and added.
// DB has [A - D). It should show up coalesced in knownBlobRanges, and [B - C) should be in added.
// DB has [A - C). It should show up coalesced in knownBlobRanges, and [C - D) should be in removed.
// DB has [B - C). It should show up coalesced in knownBlobRanges, and [A - B) should be removed.
// DB has [B - D). It should show up coalesced in knownBlobRanges, and [C - D) should be removed.
// DB has [A - D). It should show up coalesced in knownBlobRanges, and [A - B) should be removed.
// DB has [A - B) and [C - D). They should show up in knownBlobRanges, and [B - C) should be in removed.
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// DB has [B - C). It should show up in knownBlobRanges, [B - C) should be in added, and [A - B) and [C - D) should
// be in removed.
TEST_CASE(":/blobmanager/updateranges") {
KeyRangeMap<bool> knownBlobRanges(false, normalKeys.end);
Arena ar;
VectorRef<KeyRangeRef> added;
VectorRef<KeyRangeRef> removed;
StringRef active = LiteralStringRef("1");
StringRef inactive = StringRef();
RangeResult dbDataEmpty;
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std::vector<std::pair<KeyRangeRef, bool>> kbrRanges;
StringRef keyA = StringRef(ar, LiteralStringRef("A"));
StringRef keyB = StringRef(ar, LiteralStringRef("B"));
StringRef keyC = StringRef(ar, LiteralStringRef("C"));
StringRef keyD = StringRef(ar, LiteralStringRef("D"));
// db data setup
RangeResult dbDataAB;
dbDataAB.emplace_back(ar, keyA, active);
dbDataAB.emplace_back(ar, keyB, inactive);
RangeResult dbDataAC;
dbDataAC.emplace_back(ar, keyA, active);
dbDataAC.emplace_back(ar, keyC, inactive);
RangeResult dbDataAD;
dbDataAD.emplace_back(ar, keyA, active);
dbDataAD.emplace_back(ar, keyD, inactive);
RangeResult dbDataBC;
dbDataBC.emplace_back(ar, keyB, active);
dbDataBC.emplace_back(ar, keyC, inactive);
RangeResult dbDataBD;
dbDataBD.emplace_back(ar, keyB, active);
dbDataBD.emplace_back(ar, keyD, inactive);
RangeResult dbDataCD;
dbDataCD.emplace_back(ar, keyC, active);
dbDataCD.emplace_back(ar, keyD, inactive);
RangeResult dbDataAB_CD;
dbDataAB_CD.emplace_back(ar, keyA, active);
dbDataAB_CD.emplace_back(ar, keyB, inactive);
dbDataAB_CD.emplace_back(ar, keyC, active);
dbDataAB_CD.emplace_back(ar, keyD, inactive);
// key ranges setup
KeyRangeRef rangeAB = KeyRangeRef(keyA, keyB);
KeyRangeRef rangeAC = KeyRangeRef(keyA, keyC);
KeyRangeRef rangeAD = KeyRangeRef(keyA, keyD);
KeyRangeRef rangeBC = KeyRangeRef(keyB, keyC);
KeyRangeRef rangeBD = KeyRangeRef(keyB, keyD);
KeyRangeRef rangeCD = KeyRangeRef(keyC, keyD);
KeyRangeRef rangeStartToA = KeyRangeRef(normalKeys.begin, keyA);
KeyRangeRef rangeStartToB = KeyRangeRef(normalKeys.begin, keyB);
KeyRangeRef rangeStartToC = KeyRangeRef(normalKeys.begin, keyC);
KeyRangeRef rangeBToEnd = KeyRangeRef(keyB, normalKeys.end);
KeyRangeRef rangeCToEnd = KeyRangeRef(keyC, normalKeys.end);
KeyRangeRef rangeDToEnd = KeyRangeRef(keyD, normalKeys.end);
// actual test
getRanges(kbrRanges, knownBlobRanges);
ASSERT(kbrRanges.size() == 1);
ASSERT(kbrRanges[0].first == normalKeys);
ASSERT(!kbrRanges[0].second);
// DB has [A - B)
kbrRanges.clear();
added.clear();
removed.clear();
updateClientBlobRanges(&knownBlobRanges, dbDataAB, ar, &added, &removed);
ASSERT(added.size() == 1);
ASSERT(added[0] == rangeAB);
ASSERT(removed.size() == 0);
getRanges(kbrRanges, knownBlobRanges);
ASSERT(kbrRanges.size() == 3);
ASSERT(kbrRanges[0].first == rangeStartToA);
ASSERT(!kbrRanges[0].second);
ASSERT(kbrRanges[1].first == rangeAB);
ASSERT(kbrRanges[1].second);
ASSERT(kbrRanges[2].first == rangeBToEnd);
ASSERT(!kbrRanges[2].second);
// DB has nothing
kbrRanges.clear();
added.clear();
removed.clear();
updateClientBlobRanges(&knownBlobRanges, dbDataEmpty, ar, &added, &removed);
ASSERT(added.size() == 0);
ASSERT(removed.size() == 1);
ASSERT(removed[0] == rangeAB);
getRanges(kbrRanges, knownBlobRanges);
ASSERT(kbrRanges[0].first == normalKeys);
ASSERT(!kbrRanges[0].second);
// DB has [A - B) and [C - D)
kbrRanges.clear();
added.clear();
removed.clear();
updateClientBlobRanges(&knownBlobRanges, dbDataAB_CD, ar, &added, &removed);
ASSERT(added.size() == 2);
ASSERT(added[0] == rangeAB);
ASSERT(added[1] == rangeCD);
ASSERT(removed.size() == 0);
getRanges(kbrRanges, knownBlobRanges);
ASSERT(kbrRanges.size() == 5);
ASSERT(kbrRanges[0].first == rangeStartToA);
ASSERT(!kbrRanges[0].second);
ASSERT(kbrRanges[1].first == rangeAB);
ASSERT(kbrRanges[1].second);
ASSERT(kbrRanges[2].first == rangeBC);
ASSERT(!kbrRanges[2].second);
ASSERT(kbrRanges[3].first == rangeCD);
ASSERT(kbrRanges[3].second);
ASSERT(kbrRanges[4].first == rangeDToEnd);
ASSERT(!kbrRanges[4].second);
// DB has [A - D)
kbrRanges.clear();
added.clear();
removed.clear();
updateClientBlobRanges(&knownBlobRanges, dbDataAD, ar, &added, &removed);
ASSERT(added.size() == 1);
ASSERT(added[0] == rangeBC);
ASSERT(removed.size() == 0);
getRanges(kbrRanges, knownBlobRanges);
ASSERT(kbrRanges.size() == 3);
ASSERT(kbrRanges[0].first == rangeStartToA);
ASSERT(!kbrRanges[0].second);
ASSERT(kbrRanges[1].first == rangeAD);
ASSERT(kbrRanges[1].second);
ASSERT(kbrRanges[2].first == rangeDToEnd);
ASSERT(!kbrRanges[2].second);
// DB has [A - C)
kbrRanges.clear();
added.clear();
removed.clear();
updateClientBlobRanges(&knownBlobRanges, dbDataAC, ar, &added, &removed);
ASSERT(added.size() == 0);
ASSERT(removed.size() == 1);
ASSERT(removed[0] == rangeCD);
getRanges(kbrRanges, knownBlobRanges);
ASSERT(kbrRanges.size() == 3);
ASSERT(kbrRanges[0].first == rangeStartToA);
ASSERT(!kbrRanges[0].second);
ASSERT(kbrRanges[1].first == rangeAC);
ASSERT(kbrRanges[1].second);
ASSERT(kbrRanges[2].first == rangeCToEnd);
ASSERT(!kbrRanges[2].second);
// DB has [B - C)
kbrRanges.clear();
added.clear();
removed.clear();
updateClientBlobRanges(&knownBlobRanges, dbDataBC, ar, &added, &removed);
ASSERT(added.size() == 0);
ASSERT(removed.size() == 1);
ASSERT(removed[0] == rangeAB);
getRanges(kbrRanges, knownBlobRanges);
ASSERT(kbrRanges.size() == 3);
ASSERT(kbrRanges[0].first == rangeStartToB);
ASSERT(!kbrRanges[0].second);
ASSERT(kbrRanges[1].first == rangeBC);
ASSERT(kbrRanges[1].second);
ASSERT(kbrRanges[2].first == rangeCToEnd);
ASSERT(!kbrRanges[2].second);
// DB has [B - D)
kbrRanges.clear();
added.clear();
removed.clear();
updateClientBlobRanges(&knownBlobRanges, dbDataBD, ar, &added, &removed);
ASSERT(added.size() == 1);
ASSERT(added[0] == rangeCD);
ASSERT(removed.size() == 0);
getRanges(kbrRanges, knownBlobRanges);
ASSERT(kbrRanges.size() == 3);
ASSERT(kbrRanges[0].first == rangeStartToB);
ASSERT(!kbrRanges[0].second);
ASSERT(kbrRanges[1].first == rangeBD);
ASSERT(kbrRanges[1].second);
ASSERT(kbrRanges[2].first == rangeDToEnd);
ASSERT(!kbrRanges[2].second);
// DB has [A - D)
kbrRanges.clear();
added.clear();
removed.clear();
updateClientBlobRanges(&knownBlobRanges, dbDataAD, ar, &added, &removed);
ASSERT(added.size() == 1);
ASSERT(added[0] == rangeAB);
ASSERT(removed.size() == 0);
getRanges(kbrRanges, knownBlobRanges);
ASSERT(kbrRanges.size() == 3);
ASSERT(kbrRanges[0].first == rangeStartToA);
ASSERT(!kbrRanges[0].second);
ASSERT(kbrRanges[1].first == rangeAD);
ASSERT(kbrRanges[1].second);
ASSERT(kbrRanges[2].first == rangeDToEnd);
ASSERT(!kbrRanges[2].second);
// DB has [A - B) and [C - D)
kbrRanges.clear();
added.clear();
removed.clear();
updateClientBlobRanges(&knownBlobRanges, dbDataAB_CD, ar, &added, &removed);
ASSERT(added.size() == 0);
ASSERT(removed.size() == 1);
ASSERT(removed[0] == rangeBC);
getRanges(kbrRanges, knownBlobRanges);
ASSERT(kbrRanges.size() == 5);
ASSERT(kbrRanges[0].first == rangeStartToA);
ASSERT(!kbrRanges[0].second);
ASSERT(kbrRanges[1].first == rangeAB);
ASSERT(kbrRanges[1].second);
ASSERT(kbrRanges[2].first == rangeBC);
ASSERT(!kbrRanges[2].second);
ASSERT(kbrRanges[3].first == rangeCD);
ASSERT(kbrRanges[3].second);
ASSERT(kbrRanges[4].first == rangeDToEnd);
ASSERT(!kbrRanges[4].second);
// DB has [B - C)
kbrRanges.clear();
added.clear();
removed.clear();
updateClientBlobRanges(&knownBlobRanges, dbDataBC, ar, &added, &removed);
ASSERT(added.size() == 1);
ASSERT(added[0] == rangeBC);
ASSERT(removed.size() == 2);
ASSERT(removed[0] == rangeAB);
ASSERT(removed[1] == rangeCD);
getRanges(kbrRanges, knownBlobRanges);
ASSERT(kbrRanges.size() == 3);
ASSERT(kbrRanges[0].first == rangeStartToB);
ASSERT(!kbrRanges[0].second);
ASSERT(kbrRanges[1].first == rangeBC);
ASSERT(kbrRanges[1].second);
ASSERT(kbrRanges[2].first == rangeCToEnd);
ASSERT(!kbrRanges[2].second);
return Void();
}