/
resharding_coordinator_service.cpp
2053 lines (1785 loc) · 96.6 KB
/
resharding_coordinator_service.cpp
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/**
* Copyright (C) 2020-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#include "mongo/db/s/resharding/resharding_coordinator_service.h"
#include "mongo/base/string_data.h"
#include "mongo/bson/bsonobj.h"
#include "mongo/bson/json.h"
#include "mongo/db/auth/authorization_session_impl.h"
#include "mongo/db/dbdirectclient.h"
#include "mongo/db/logical_session_cache.h"
#include "mongo/db/ops/write_ops.h"
#include "mongo/db/repl/primary_only_service.h"
#include "mongo/db/repl/repl_client_info.h"
#include "mongo/db/repl/wait_for_majority_service.h"
#include "mongo/db/s/balancer/balance_stats.h"
#include "mongo/db/s/balancer/balancer_policy.h"
#include "mongo/db/s/config/initial_split_policy.h"
#include "mongo/db/s/config/sharding_catalog_manager.h"
#include "mongo/db/s/resharding/resharding_coordinator_commit_monitor.h"
#include "mongo/db/s/resharding/resharding_future_util.h"
#include "mongo/db/s/resharding/resharding_server_parameters_gen.h"
#include "mongo/db/s/resharding/resharding_util.h"
#include "mongo/db/s/sharding_data_transform_cumulative_metrics.h"
#include "mongo/db/s/sharding_data_transform_metrics.h"
#include "mongo/db/s/sharding_ddl_util.h"
#include "mongo/db/s/sharding_logging.h"
#include "mongo/db/s/sharding_util.h"
#include "mongo/db/storage/duplicate_key_error_info.h"
#include "mongo/db/vector_clock.h"
#include "mongo/db/write_concern_options.h"
#include "mongo/logv2/log.h"
#include "mongo/rpc/get_status_from_command_result.h"
#include "mongo/s/catalog/type_chunk.h"
#include "mongo/s/catalog/type_tags.h"
#include "mongo/s/grid.h"
#include "mongo/s/request_types/abort_reshard_collection_gen.h"
#include "mongo/s/request_types/commit_reshard_collection_gen.h"
#include "mongo/s/request_types/drop_collection_if_uuid_not_matching_gen.h"
#include "mongo/s/request_types/flush_resharding_state_change_gen.h"
#include "mongo/s/request_types/flush_routing_table_cache_updates_gen.h"
#include "mongo/s/shard_id.h"
#include "mongo/s/write_ops/batched_command_request.h"
#include "mongo/s/write_ops/batched_command_response.h"
#include "mongo/util/assert_util.h"
#include "mongo/util/fail_point.h"
#include "mongo/util/future_util.h"
#include "mongo/util/string_map.h"
#include "mongo/util/uuid.h"
#define MONGO_LOGV2_DEFAULT_COMPONENT ::mongo::logv2::LogComponent::kResharding
namespace mongo {
namespace {
using namespace fmt::literals;
MONGO_FAIL_POINT_DEFINE(reshardingPauseCoordinatorAfterPreparingToDonate);
MONGO_FAIL_POINT_DEFINE(reshardingPauseCoordinatorBeforeInitializing);
MONGO_FAIL_POINT_DEFINE(reshardingPauseCoordinatorBeforeCloning);
MONGO_FAIL_POINT_DEFINE(reshardingPauseCoordinatorBeforeBlockingWrites);
MONGO_FAIL_POINT_DEFINE(reshardingPauseCoordinatorBeforeDecisionPersisted);
MONGO_FAIL_POINT_DEFINE(reshardingPauseCoordinatorBeforeRemovingStateDoc);
MONGO_FAIL_POINT_DEFINE(reshardingPauseCoordinatorBeforeCompletion);
MONGO_FAIL_POINT_DEFINE(reshardingPauseCoordinatorBeforeStartingErrorFlow);
MONGO_FAIL_POINT_DEFINE(reshardingPauseCoordinatorBeforePersistingStateTransition);
MONGO_FAIL_POINT_DEFINE(pauseBeforeTellDonorToRefresh);
MONGO_FAIL_POINT_DEFINE(pauseBeforeInsertCoordinatorDoc);
const std::string kReshardingCoordinatorActiveIndexName = "ReshardingCoordinatorActiveIndex";
const Backoff kExponentialBackoff(Seconds(1), Milliseconds::max());
const WriteConcernOptions kMajorityWriteConcern{
WriteConcernOptions::kMajority, WriteConcernOptions::SyncMode::UNSET, Seconds(0)};
bool shouldStopAttemptingToCreateIndex(Status status, const CancellationToken& token) {
return status.isOK() || token.isCanceled();
}
Date_t getCurrentTime() {
const auto svcCtx = cc().getServiceContext();
return svcCtx->getFastClockSource()->now();
}
void assertNumDocsModifiedMatchesExpected(const BatchedCommandRequest& request,
const BSONObj& response,
int expected) {
auto numDocsModified = response.getIntField("n");
uassert(5030401,
str::stream() << "Expected to match " << expected << " docs, but only matched "
<< numDocsModified << " for write request " << request.toString(),
expected == numDocsModified);
}
void appendShardEntriesToSetBuilder(const ReshardingCoordinatorDocument& coordinatorDoc,
BSONObjBuilder& setBuilder) {
BSONArrayBuilder donorShards(
setBuilder.subarrayStart(ReshardingCoordinatorDocument::kDonorShardsFieldName));
for (const auto& donorShard : coordinatorDoc.getDonorShards()) {
donorShards.append(donorShard.toBSON());
}
donorShards.doneFast();
BSONArrayBuilder recipientShards(
setBuilder.subarrayStart(ReshardingCoordinatorDocument::kRecipientShardsFieldName));
for (const auto& recipientShard : coordinatorDoc.getRecipientShards()) {
recipientShards.append(recipientShard.toBSON());
}
recipientShards.doneFast();
}
void unsetInitializingFields(BSONObjBuilder& updateBuilder) {
BSONObjBuilder unsetBuilder(updateBuilder.subobjStart("$unset"));
unsetBuilder.append(ReshardingCoordinatorDocument::kPresetReshardedChunksFieldName, "");
unsetBuilder.append(ReshardingCoordinatorDocument::kZonesFieldName, "");
unsetBuilder.doneFast();
}
using resharding_metrics::getIntervalEndFieldName;
using resharding_metrics::getIntervalStartFieldName;
using DocT = ReshardingCoordinatorDocument;
const auto metricsPrefix = resharding_metrics::getMetricsPrefix<DocT>();
void buildStateDocumentCloneMetricsForUpdate(BSONObjBuilder& bob, ReshardingMetrics* metrics) {
bob.append(getIntervalStartFieldName<DocT>(ReshardingRecipientMetrics::kDocumentCopyFieldName),
metrics->getCopyingBegin());
}
void buildStateDocumentApplyMetricsForUpdate(BSONObjBuilder& bob, ReshardingMetrics* metrics) {
bob.append(getIntervalEndFieldName<DocT>(ReshardingRecipientMetrics::kDocumentCopyFieldName),
metrics->getCopyingEnd());
bob.append(
getIntervalEndFieldName<DocT>(ReshardingRecipientMetrics::kOplogApplicationFieldName),
metrics->getApplyingBegin());
}
void buildStateDocumentBlockingWritesMetricsForUpdate(BSONObjBuilder& bob,
ReshardingMetrics* metrics) {
bob.append(
getIntervalEndFieldName<DocT>(ReshardingRecipientMetrics::kOplogApplicationFieldName),
metrics->getApplyingEnd());
}
void buildStateDocumentMetricsForUpdate(BSONObjBuilder& bob,
ReshardingMetrics* metrics,
CoordinatorStateEnum newState) {
switch (newState) {
case CoordinatorStateEnum::kCloning:
buildStateDocumentCloneMetricsForUpdate(bob, metrics);
return;
case CoordinatorStateEnum::kApplying:
buildStateDocumentApplyMetricsForUpdate(bob, metrics);
return;
case CoordinatorStateEnum::kBlockingWrites:
buildStateDocumentBlockingWritesMetricsForUpdate(bob, metrics);
return;
default:
return;
}
}
void writeToCoordinatorStateNss(OperationContext* opCtx,
ReshardingMetrics* metrics,
const ReshardingCoordinatorDocument& coordinatorDoc,
TxnNumber txnNumber) {
BatchedCommandRequest request([&] {
auto nextState = coordinatorDoc.getState();
switch (nextState) {
case CoordinatorStateEnum::kInitializing:
// Insert the new coordinator document.
return BatchedCommandRequest::buildInsertOp(
NamespaceString::kConfigReshardingOperationsNamespace,
std::vector<BSONObj>{coordinatorDoc.toBSON()});
case CoordinatorStateEnum::kDone:
// Remove the coordinator document.
return BatchedCommandRequest::buildDeleteOp(
NamespaceString::kConfigReshardingOperationsNamespace,
BSON("_id" << coordinatorDoc.getReshardingUUID()), // query
false // multi
);
default: {
// Partially update the coordinator document.
BSONObjBuilder updateBuilder;
{
BSONObjBuilder setBuilder(updateBuilder.subobjStart("$set"));
// Always update the state field.
setBuilder.append(ReshardingCoordinatorDocument::kStateFieldName,
CoordinatorState_serializer(coordinatorDoc.getState()));
if (auto cloneTimestamp = coordinatorDoc.getCloneTimestamp()) {
// If the cloneTimestamp exists, include it in the update.
setBuilder.append(ReshardingCoordinatorDocument::kCloneTimestampFieldName,
*cloneTimestamp);
}
if (auto abortReason = coordinatorDoc.getAbortReason()) {
// If the abortReason exists, include it in the update.
setBuilder.append(ReshardingCoordinatorDocument::kAbortReasonFieldName,
*abortReason);
}
if (auto approxBytesToCopy = coordinatorDoc.getApproxBytesToCopy()) {
// If the approxBytesToCopy exists, include it in the update.
setBuilder.append(
ReshardingCoordinatorDocument::kApproxBytesToCopyFieldName,
*approxBytesToCopy);
}
if (auto approxDocumentsToCopy = coordinatorDoc.getApproxDocumentsToCopy()) {
// If the approxDocumentsToCopy exists, include it in the update.
setBuilder.append(
ReshardingCoordinatorDocument::kApproxDocumentsToCopyFieldName,
*approxDocumentsToCopy);
}
buildStateDocumentMetricsForUpdate(setBuilder, metrics, nextState);
if (nextState == CoordinatorStateEnum::kPreparingToDonate) {
appendShardEntriesToSetBuilder(coordinatorDoc, setBuilder);
setBuilder.doneFast();
unsetInitializingFields(updateBuilder);
}
}
return BatchedCommandRequest::buildUpdateOp(
NamespaceString::kConfigReshardingOperationsNamespace,
BSON("_id" << coordinatorDoc.getReshardingUUID()),
updateBuilder.obj(),
false, // upsert
false // multi
);
}
}
}());
auto expectedNumModified = (request.getBatchType() == BatchedCommandRequest::BatchType_Insert)
? boost::none
: boost::make_optional(1);
auto res = ShardingCatalogManager::get(opCtx)->writeToConfigDocumentInTxn(
opCtx, NamespaceString::kConfigReshardingOperationsNamespace, request, txnNumber);
if (expectedNumModified) {
assertNumDocsModifiedMatchesExpected(request, res, *expectedNumModified);
}
}
/**
* Creates reshardingFields.recipientFields for the resharding operation. Note: these should not
* change once the operation has begun.
*/
TypeCollectionRecipientFields constructRecipientFields(
const ReshardingCoordinatorDocument& coordinatorDoc) {
std::vector<DonorShardFetchTimestamp> donorShards;
for (const auto& donor : coordinatorDoc.getDonorShards()) {
DonorShardFetchTimestamp donorFetchTimestamp(donor.getId());
donorFetchTimestamp.setMinFetchTimestamp(donor.getMutableState().getMinFetchTimestamp());
donorShards.push_back(std::move(donorFetchTimestamp));
}
TypeCollectionRecipientFields recipientFields(
std::move(donorShards),
coordinatorDoc.getSourceUUID(),
coordinatorDoc.getSourceNss(),
resharding::gReshardingMinimumOperationDurationMillis.load());
resharding::emplaceCloneTimestampIfExists(recipientFields, coordinatorDoc.getCloneTimestamp());
resharding::emplaceApproxBytesToCopyIfExists(
recipientFields, coordinatorDoc.getReshardingApproxCopySizeStruct());
return recipientFields;
}
BSONObj createReshardingFieldsUpdateForOriginalNss(
OperationContext* opCtx,
const ReshardingCoordinatorDocument& coordinatorDoc,
boost::optional<OID> newCollectionEpoch,
boost::optional<Timestamp> newCollectionTimestamp) {
auto nextState = coordinatorDoc.getState();
switch (nextState) {
case CoordinatorStateEnum::kInitializing: {
// Append 'reshardingFields' to the config.collections entry for the original nss
TypeCollectionReshardingFields originalEntryReshardingFields(
coordinatorDoc.getReshardingUUID());
originalEntryReshardingFields.setState(coordinatorDoc.getState());
originalEntryReshardingFields.setStartTime(coordinatorDoc.getStartTime());
return BSON("$set" << BSON(CollectionType::kReshardingFieldsFieldName
<< originalEntryReshardingFields.toBSON()
<< CollectionType::kUpdatedAtFieldName
<< opCtx->getServiceContext()->getPreciseClockSource()->now()
<< CollectionType::kAllowMigrationsFieldName << false));
}
case CoordinatorStateEnum::kPreparingToDonate: {
TypeCollectionDonorFields donorFields(coordinatorDoc.getTempReshardingNss(),
coordinatorDoc.getReshardingKey(),
resharding::extractShardIdsFromParticipantEntries(
coordinatorDoc.getRecipientShards()));
BSONObjBuilder updateBuilder;
{
BSONObjBuilder setBuilder(updateBuilder.subobjStart("$set"));
{
setBuilder.append(CollectionType::kReshardingFieldsFieldName + "." +
TypeCollectionReshardingFields::kStateFieldName,
CoordinatorState_serializer(nextState));
setBuilder.append(CollectionType::kReshardingFieldsFieldName + "." +
TypeCollectionReshardingFields::kDonorFieldsFieldName,
donorFields.toBSON());
setBuilder.append(CollectionType::kUpdatedAtFieldName,
opCtx->getServiceContext()->getPreciseClockSource()->now());
}
setBuilder.doneFast();
}
return updateBuilder.obj();
}
case CoordinatorStateEnum::kCommitting: {
// Update the config.collections entry for the original nss to reflect the new sharded
// collection. Set 'uuid' to the reshardingUUID, 'key' to the new shard key,
// 'lastmodEpoch' to newCollectionEpoch, and 'timestamp' to newCollectionTimestamp. Also
// update the 'state' field and add the 'recipientFields' to the 'reshardingFields'
// section.
auto recipientFields = constructRecipientFields(coordinatorDoc);
BSONObj setFields =
BSON("uuid" << coordinatorDoc.getReshardingUUID() << "key"
<< coordinatorDoc.getReshardingKey().toBSON() << "lastmodEpoch"
<< newCollectionEpoch.get() << "lastmod"
<< opCtx->getServiceContext()->getPreciseClockSource()->now()
<< "reshardingFields.state"
<< CoordinatorState_serializer(coordinatorDoc.getState()).toString()
<< "reshardingFields.recipientFields" << recipientFields.toBSON());
if (newCollectionTimestamp.has_value()) {
setFields = setFields.addFields(BSON("timestamp" << newCollectionTimestamp.get()));
}
return BSON("$set" << setFields);
}
case mongo::CoordinatorStateEnum::kDone:
// Remove 'reshardingFields' from the config.collections entry
return BSON(
"$unset" << BSON(CollectionType::kReshardingFieldsFieldName
<< "" << CollectionType::kAllowMigrationsFieldName << "")
<< "$set"
<< BSON(CollectionType::kUpdatedAtFieldName
<< opCtx->getServiceContext()->getPreciseClockSource()->now()));
default: {
// Update the 'state' field, and 'abortReason' field if it exists, in the
// 'reshardingFields' section.
BSONObjBuilder updateBuilder;
{
BSONObjBuilder setBuilder(updateBuilder.subobjStart("$set"));
setBuilder.append("reshardingFields.state",
CoordinatorState_serializer(nextState).toString());
setBuilder.append("lastmod",
opCtx->getServiceContext()->getPreciseClockSource()->now());
if (auto abortReason = coordinatorDoc.getAbortReason()) {
// If the abortReason exists, include it in the update.
setBuilder.append("reshardingFields.abortReason", *abortReason);
auto abortStatus = resharding::getStatusFromAbortReason(coordinatorDoc);
setBuilder.append("reshardingFields.userCanceled",
abortStatus == ErrorCodes::ReshardCollectionAborted);
}
setBuilder.doneFast();
if (coordinatorDoc.getAbortReason()) {
updateBuilder.append("$unset",
BSON(CollectionType::kAllowMigrationsFieldName << ""));
}
}
return updateBuilder.obj();
}
}
}
void updateConfigCollectionsForOriginalNss(OperationContext* opCtx,
const ReshardingCoordinatorDocument& coordinatorDoc,
boost::optional<OID> newCollectionEpoch,
boost::optional<Timestamp> newCollectionTimestamp,
TxnNumber txnNumber) {
auto writeOp = createReshardingFieldsUpdateForOriginalNss(
opCtx, coordinatorDoc, newCollectionEpoch, newCollectionTimestamp);
auto request = BatchedCommandRequest::buildUpdateOp(
CollectionType::ConfigNS,
BSON(CollectionType::kNssFieldName << coordinatorDoc.getSourceNss().ns()), // query
writeOp,
false, // upsert
false // multi
);
auto res = ShardingCatalogManager::get(opCtx)->writeToConfigDocumentInTxn(
opCtx, CollectionType::ConfigNS, request, txnNumber);
assertNumDocsModifiedMatchesExpected(request, res, 1 /* expected */);
}
void writeToConfigCollectionsForTempNss(OperationContext* opCtx,
const ReshardingCoordinatorDocument& coordinatorDoc,
boost::optional<ChunkVersion> chunkVersion,
boost::optional<const BSONObj&> collation,
TxnNumber txnNumber) {
BatchedCommandRequest request([&] {
auto nextState = coordinatorDoc.getState();
switch (nextState) {
case CoordinatorStateEnum::kPreparingToDonate: {
// Insert new entry for the temporary nss into config.collections
auto collType = resharding::createTempReshardingCollectionType(
opCtx, coordinatorDoc, chunkVersion.get(), collation.get());
return BatchedCommandRequest::buildInsertOp(
CollectionType::ConfigNS, std::vector<BSONObj>{collType.toBSON()});
}
case CoordinatorStateEnum::kCloning: {
// Update the 'state', 'donorShards', 'approxCopySize', and 'cloneTimestamp' fields
// in the 'reshardingFields.recipient' section
BSONArrayBuilder donorShardsBuilder;
for (const auto& donor : coordinatorDoc.getDonorShards()) {
DonorShardFetchTimestamp donorShardFetchTimestamp(donor.getId());
donorShardFetchTimestamp.setMinFetchTimestamp(
donor.getMutableState().getMinFetchTimestamp());
donorShardsBuilder.append(donorShardFetchTimestamp.toBSON());
}
return BatchedCommandRequest::buildUpdateOp(
CollectionType::ConfigNS,
BSON(CollectionType::kNssFieldName
<< coordinatorDoc.getTempReshardingNss().ns()),
BSON("$set" << BSON(
"reshardingFields.state"
<< CoordinatorState_serializer(nextState).toString()
<< "reshardingFields.recipientFields.approxDocumentsToCopy"
<< coordinatorDoc.getApproxDocumentsToCopy().get()
<< "reshardingFields.recipientFields.approxBytesToCopy"
<< coordinatorDoc.getApproxBytesToCopy().get()
<< "reshardingFields.recipientFields.cloneTimestamp"
<< coordinatorDoc.getCloneTimestamp().get()
<< "reshardingFields.recipientFields.donorShards"
<< donorShardsBuilder.arr() << "lastmod"
<< opCtx->getServiceContext()->getPreciseClockSource()->now())),
false, // upsert
false // multi
);
}
case CoordinatorStateEnum::kCommitting:
// Remove the entry for the temporary nss
return BatchedCommandRequest::buildDeleteOp(
CollectionType::ConfigNS,
BSON(CollectionType::kNssFieldName
<< coordinatorDoc.getTempReshardingNss().ns()),
false // multi
);
default: {
// Update the 'state' field, and 'abortReason' field if it exists, in the
// 'reshardingFields' section.
BSONObjBuilder updateBuilder;
{
BSONObjBuilder setBuilder(updateBuilder.subobjStart("$set"));
setBuilder.append("reshardingFields.state",
CoordinatorState_serializer(nextState).toString());
setBuilder.append("lastmod",
opCtx->getServiceContext()->getPreciseClockSource()->now());
if (auto abortReason = coordinatorDoc.getAbortReason()) {
setBuilder.append("reshardingFields.abortReason", *abortReason);
auto abortStatus = resharding::getStatusFromAbortReason(coordinatorDoc);
setBuilder.append("reshardingFields.userCanceled",
abortStatus == ErrorCodes::ReshardCollectionAborted);
}
}
return BatchedCommandRequest::buildUpdateOp(
CollectionType::ConfigNS,
BSON(CollectionType::kNssFieldName
<< coordinatorDoc.getTempReshardingNss().ns()),
updateBuilder.obj(),
true, // upsert
false // multi
);
}
}
}());
auto expectedNumModified = (request.getBatchType() == BatchedCommandRequest::BatchType_Insert)
? boost::none
: boost::make_optional(1);
auto res = ShardingCatalogManager::get(opCtx)->writeToConfigDocumentInTxn(
opCtx, CollectionType::ConfigNS, request, txnNumber);
if (expectedNumModified) {
assertNumDocsModifiedMatchesExpected(request, res, *expectedNumModified);
}
}
void insertChunkAndTagDocsForTempNss(OperationContext* opCtx,
const std::vector<ChunkType>& initialChunks,
std::vector<BSONObj> newZones) {
// Insert new initial chunk documents for temp nss
std::vector<BSONObj> initialChunksBSON(initialChunks.size());
std::transform(initialChunks.begin(),
initialChunks.end(),
initialChunksBSON.begin(),
[](ChunkType chunk) { return chunk.toConfigBSON(); });
ShardingCatalogManager::get(opCtx)->insertConfigDocuments(
opCtx, ChunkType::ConfigNS, std::move(initialChunksBSON));
ShardingCatalogManager::get(opCtx)->insertConfigDocuments(opCtx, TagsType::ConfigNS, newZones);
}
// Requires that there be no session information on the opCtx.
void removeChunkAndTagsDocs(OperationContext* opCtx,
const BSONObj& tagsQuery,
const UUID& collUUID) {
// Remove all chunk documents for the original nss. We do not know how many chunk docs
// currently exist, so cannot pass a value for expectedNumModified
const auto chunksQuery = BSON(ChunkType::collectionUUID() << collUUID);
const auto tagDeleteOperationHint = BSON(TagsType::ns() << 1 << TagsType::min() << 1);
const auto catalogClient = Grid::get(opCtx)->catalogClient();
uassertStatusOK(catalogClient->removeConfigDocuments(
opCtx, ChunkType::ConfigNS, chunksQuery, kMajorityWriteConcern));
uassertStatusOK(catalogClient->removeConfigDocuments(
opCtx, TagsType::ConfigNS, tagsQuery, kMajorityWriteConcern, tagDeleteOperationHint));
}
void updateChunkAndTagsDocsForTempNss(OperationContext* opCtx,
const ReshardingCoordinatorDocument& coordinatorDoc,
OID newCollectionEpoch,
TxnNumber txnNumber) {
auto hint = BSON("ns" << 1 << "min" << 1);
auto tagsRequest = BatchedCommandRequest::buildUpdateOp(
TagsType::ConfigNS,
BSON(TagsType::ns(coordinatorDoc.getTempReshardingNss().ns())), // query
BSON("$set" << BSON("ns" << coordinatorDoc.getSourceNss().ns())), // update
false, // upsert
true, // multi
hint // hint
);
// Update the 'ns' field to be the original collection namespace for all tags documents that
// currently have 'ns' as the temporary collection namespace
auto tagsRes = ShardingCatalogManager::get(opCtx)->writeToConfigDocumentInTxn(
opCtx, TagsType::ConfigNS, tagsRequest, txnNumber);
}
/**
* Executes metadata changes in a transaction without bumping the collection version.
*/
void executeMetadataChangesInTxn(
OperationContext* opCtx,
unique_function<void(OperationContext*, TxnNumber)> changeMetadataFunc) {
ShardingCatalogManager::withTransaction(opCtx,
NamespaceString::kConfigReshardingOperationsNamespace,
std::move(changeMetadataFunc),
ShardingCatalogClient::kLocalWriteConcern);
}
BSONObj makeFlushRoutingTableCacheUpdatesCmd(const NamespaceString& nss) {
auto cmd = FlushRoutingTableCacheUpdatesWithWriteConcern(nss);
cmd.setSyncFromConfig(true);
cmd.setDbName(nss.db());
return cmd.toBSON(
BSON(WriteConcernOptions::kWriteConcernField << kMajorityWriteConcern.toBSON()));
}
ReshardingMetrics::CoordinatorState toMetricsState(CoordinatorStateEnum state) {
return ReshardingMetrics::CoordinatorState(state);
}
} // namespace
namespace resharding {
CollectionType createTempReshardingCollectionType(
OperationContext* opCtx,
const ReshardingCoordinatorDocument& coordinatorDoc,
const ChunkVersion& chunkVersion,
const BSONObj& collation) {
CollectionType collType(coordinatorDoc.getTempReshardingNss(),
chunkVersion.epoch(),
chunkVersion.getTimestamp(),
opCtx->getServiceContext()->getPreciseClockSource()->now(),
coordinatorDoc.getReshardingUUID(),
coordinatorDoc.getReshardingKey());
collType.setDefaultCollation(collation);
TypeCollectionReshardingFields tempEntryReshardingFields(coordinatorDoc.getReshardingUUID());
tempEntryReshardingFields.setState(coordinatorDoc.getState());
tempEntryReshardingFields.setStartTime(coordinatorDoc.getStartTime());
auto recipientFields = constructRecipientFields(coordinatorDoc);
tempEntryReshardingFields.setRecipientFields(std::move(recipientFields));
collType.setReshardingFields(std::move(tempEntryReshardingFields));
collType.setAllowMigrations(false);
return collType;
}
void cleanupSourceConfigCollections(OperationContext* opCtx,
const ReshardingCoordinatorDocument& coordinatorDoc) {
using Doc = Document;
using Arr = std::vector<Value>;
using V = Value;
auto createTagFilter = [](const V value) {
return V{Doc{{"$map",
V{Doc{{"input", V{Doc{{"$objectToArray", value}}}},
{"in", V{StringData("$$this.k")}}}}}}};
};
auto skipNewTagsFilter = Doc{
{"$ne",
Arr{createTagFilter(V{StringData("$min")}),
createTagFilter(V{Doc{{"$literal", coordinatorDoc.getReshardingKey().toBSON()}}})}}};
const auto removeTagsQuery =
BSON(TagsType::ns(coordinatorDoc.getSourceNss().ns()) << "$expr" << skipNewTagsFilter);
removeChunkAndTagsDocs(opCtx, removeTagsQuery, coordinatorDoc.getSourceUUID());
}
void writeDecisionPersistedState(OperationContext* opCtx,
ReshardingMetrics* metrics,
const ReshardingCoordinatorDocument& coordinatorDoc,
OID newCollectionEpoch,
Timestamp newCollectionTimestamp) {
// No need to bump originalNss version because its epoch will be changed.
executeMetadataChangesInTxn(
opCtx,
[&metrics, &coordinatorDoc, &newCollectionEpoch, &newCollectionTimestamp](
OperationContext* opCtx, TxnNumber txnNumber) {
// Update the config.reshardingOperations entry
writeToCoordinatorStateNss(opCtx, metrics, coordinatorDoc, txnNumber);
// Remove the config.collections entry for the temporary collection
writeToConfigCollectionsForTempNss(
opCtx, coordinatorDoc, boost::none, boost::none, txnNumber);
// Update the config.collections entry for the original namespace to reflect the new
// shard key, new epoch, and new UUID
updateConfigCollectionsForOriginalNss(
opCtx, coordinatorDoc, newCollectionEpoch, newCollectionTimestamp, txnNumber);
updateChunkAndTagsDocsForTempNss(opCtx, coordinatorDoc, newCollectionEpoch, txnNumber);
});
}
void insertCoordDocAndChangeOrigCollEntry(OperationContext* opCtx,
ReshardingMetrics* metrics,
const ReshardingCoordinatorDocument& coordinatorDoc) {
ShardingCatalogManager::get(opCtx)->bumpCollectionVersionAndChangeMetadataInTxn(
opCtx,
coordinatorDoc.getSourceNss(),
[&](OperationContext* opCtx, TxnNumber txnNumber) {
auto doc = ShardingCatalogManager::get(opCtx)->findOneConfigDocumentInTxn(
opCtx,
CollectionType::ConfigNS,
txnNumber,
BSON(CollectionType::kNssFieldName << coordinatorDoc.getSourceNss().ns()));
uassert(5808200,
str::stream() << "config.collection entry not found for "
<< coordinatorDoc.getSourceNss().ns(),
doc);
CollectionType configCollDoc(*doc);
uassert(5808201,
str::stream() << "collection " << CollectionType::kAllowMigrationsFieldName
<< " setting is already set to false",
configCollDoc.getAllowMigrations());
// Insert the coordinator document to config.reshardingOperations.
invariant(coordinatorDoc.getActive());
try {
writeToCoordinatorStateNss(opCtx, metrics, coordinatorDoc, txnNumber);
} catch (const ExceptionFor<ErrorCodes::DuplicateKey>& ex) {
auto extraInfo = ex.extraInfo<DuplicateKeyErrorInfo>();
if (extraInfo->getKeyPattern().woCompare(BSON("active" << 1)) == 0) {
uasserted(ErrorCodes::ReshardCollectionInProgress,
str::stream()
<< "Only one resharding operation is allowed to be active at a "
"time, aborting resharding op for "
<< coordinatorDoc.getSourceNss());
}
throw;
}
// Update the config.collections entry for the original collection to include
// 'reshardingFields'
updateConfigCollectionsForOriginalNss(
opCtx, coordinatorDoc, boost::none, boost::none, txnNumber);
},
ShardingCatalogClient::kLocalWriteConcern);
}
void writeParticipantShardsAndTempCollInfo(
OperationContext* opCtx,
ReshardingMetrics* metrics,
const ReshardingCoordinatorDocument& updatedCoordinatorDoc,
std::vector<ChunkType> initialChunks,
std::vector<BSONObj> zones) {
const auto tagsQuery = BSON(TagsType::ns(updatedCoordinatorDoc.getTempReshardingNss().ns()));
removeChunkAndTagsDocs(opCtx, tagsQuery, updatedCoordinatorDoc.getReshardingUUID());
insertChunkAndTagDocsForTempNss(opCtx, initialChunks, zones);
ShardingCatalogManager::get(opCtx)->bumpCollectionVersionAndChangeMetadataInTxn(
opCtx,
updatedCoordinatorDoc.getSourceNss(),
[&](OperationContext* opCtx, TxnNumber txnNumber) {
// Insert the config.collections entry for the temporary resharding collection. The
// chunks all have the same epoch, so picking the last chunk here is arbitrary.
invariant(initialChunks.size() != 0);
auto chunkVersion = initialChunks.back().getVersion();
writeToConfigCollectionsForTempNss(
opCtx, updatedCoordinatorDoc, chunkVersion, CollationSpec::kSimpleSpec, txnNumber);
// Update on-disk state to reflect latest state transition.
writeToCoordinatorStateNss(opCtx, metrics, updatedCoordinatorDoc, txnNumber);
updateConfigCollectionsForOriginalNss(
opCtx, updatedCoordinatorDoc, boost::none, boost::none, txnNumber);
},
ShardingCatalogClient::kLocalWriteConcern);
}
void writeStateTransitionAndCatalogUpdatesThenBumpShardVersions(
OperationContext* opCtx,
ReshardingMetrics* metrics,
const ReshardingCoordinatorDocument& coordinatorDoc) {
// Run updates to config.reshardingOperations and config.collections in a transaction
auto nextState = coordinatorDoc.getState();
std::vector<NamespaceString> collNames = {coordinatorDoc.getSourceNss()};
if (nextState < CoordinatorStateEnum::kCommitting) {
collNames.emplace_back(coordinatorDoc.getTempReshardingNss());
}
ShardingCatalogManager::get(opCtx)->bumpMultipleCollectionVersionsAndChangeMetadataInTxn(
opCtx,
collNames,
[&](OperationContext* opCtx, TxnNumber txnNumber) {
// Update the config.reshardingOperations entry
writeToCoordinatorStateNss(opCtx, metrics, coordinatorDoc, txnNumber);
// Update the config.collections entry for the original collection
updateConfigCollectionsForOriginalNss(
opCtx, coordinatorDoc, boost::none, boost::none, txnNumber);
// Update the config.collections entry for the temporary resharding collection. If we've
// already successfully committed that the operation will succeed, we've removed the
// entry for the temporary collection and updated the entry with original namespace to
// have the new shard key, UUID, and epoch
if (nextState < CoordinatorStateEnum::kCommitting) {
writeToConfigCollectionsForTempNss(
opCtx, coordinatorDoc, boost::none, boost::none, txnNumber);
}
},
ShardingCatalogClient::kLocalWriteConcern);
}
void removeCoordinatorDocAndReshardingFields(OperationContext* opCtx,
ReshardingMetrics* metrics,
const ReshardingCoordinatorDocument& coordinatorDoc,
boost::optional<Status> abortReason) {
// If the coordinator needs to abort and isn't in kInitializing, additional collections need to
// be cleaned up in the final transaction. Otherwise, cleanup for abort and success are the
// same.
const bool wasDecisionPersisted =
coordinatorDoc.getState() == CoordinatorStateEnum::kCommitting;
invariant((wasDecisionPersisted && !abortReason) || abortReason);
ReshardingCoordinatorDocument updatedCoordinatorDoc = coordinatorDoc;
updatedCoordinatorDoc.setState(CoordinatorStateEnum::kDone);
emplaceTruncatedAbortReasonIfExists(updatedCoordinatorDoc, abortReason);
const auto tagsQuery = BSON(TagsType::ns(coordinatorDoc.getTempReshardingNss().ns()));
// Once the decision has been persisted, the coordinator would have modified the
// config.chunks and config.collections entry. This means that the UUID of the
// non-temp collection is now the UUID of what was previously the UUID of the temp
// collection. So don't try to call remove as it will end up removing the metadata
// for the real collection.
if (!wasDecisionPersisted) {
const auto catalogClient = Grid::get(opCtx)->catalogClient();
uassertStatusOK(catalogClient->removeConfigDocuments(
opCtx,
CollectionType::ConfigNS,
BSON(CollectionType::kNssFieldName << coordinatorDoc.getTempReshardingNss().ns()),
kMajorityWriteConcern));
removeChunkAndTagsDocs(opCtx, tagsQuery, coordinatorDoc.getReshardingUUID());
}
ShardingCatalogManager::get(opCtx)->bumpCollectionVersionAndChangeMetadataInTxn(
opCtx,
updatedCoordinatorDoc.getSourceNss(),
[&](OperationContext* opCtx, TxnNumber txnNumber) {
// Remove entry for this resharding operation from config.reshardingOperations
writeToCoordinatorStateNss(opCtx, metrics, updatedCoordinatorDoc, txnNumber);
// Remove the resharding fields from the config.collections entry
updateConfigCollectionsForOriginalNss(
opCtx, updatedCoordinatorDoc, boost::none, boost::none, txnNumber);
},
ShardingCatalogClient::kLocalWriteConcern);
metrics->onStateTransition(toMetricsState(coordinatorDoc.getState()),
toMetricsState(updatedCoordinatorDoc.getState()));
}
} // namespace resharding
ChunkVersion ReshardingCoordinatorExternalState::calculateChunkVersionForInitialChunks(
OperationContext* opCtx) {
const auto now = VectorClock::get(opCtx)->getTime();
const auto timestamp = now.clusterTime().asTimestamp();
return ChunkVersion({OID::gen(), timestamp}, {1, 0});
}
std::vector<DonorShardEntry> constructDonorShardEntries(const std::set<ShardId>& donorShardIds) {
std::vector<DonorShardEntry> donorShards;
std::transform(donorShardIds.begin(),
donorShardIds.end(),
std::back_inserter(donorShards),
[](const ShardId& shardId) -> DonorShardEntry {
DonorShardContext donorCtx;
donorCtx.setState(DonorStateEnum::kUnused);
return DonorShardEntry{shardId, std::move(donorCtx)};
});
return donorShards;
}
std::vector<RecipientShardEntry> constructRecipientShardEntries(
const std::set<ShardId>& recipientShardIds) {
std::vector<RecipientShardEntry> recipientShards;
std::transform(recipientShardIds.begin(),
recipientShardIds.end(),
std::back_inserter(recipientShards),
[](const ShardId& shardId) -> RecipientShardEntry {
RecipientShardContext recipientCtx;
recipientCtx.setState(RecipientStateEnum::kUnused);
return RecipientShardEntry{shardId, std::move(recipientCtx)};
});
return recipientShards;
}
ReshardingCoordinatorExternalState::ParticipantShardsAndChunks
ReshardingCoordinatorExternalStateImpl::calculateParticipantShardsAndChunks(
OperationContext* opCtx, const ReshardingCoordinatorDocument& coordinatorDoc) {
const auto cm = uassertStatusOK(
Grid::get(opCtx)->catalogCache()->getShardedCollectionRoutingInfoWithRefresh(
opCtx, coordinatorDoc.getSourceNss()));
std::set<ShardId> donorShardIds;
cm.getAllShardIds(&donorShardIds);
std::set<ShardId> recipientShardIds;
std::vector<ChunkType> initialChunks;
// The database primary must always be a recipient to ensure it ends up with consistent
// collection metadata.
recipientShardIds.emplace(cm.dbPrimary());
if (const auto& chunks = coordinatorDoc.getPresetReshardedChunks()) {
auto version = calculateChunkVersionForInitialChunks(opCtx);
// Use the provided shardIds from presetReshardedChunks to construct the
// recipient list.
for (const auto& reshardedChunk : *chunks) {
recipientShardIds.emplace(reshardedChunk.getRecipientShardId());
initialChunks.emplace_back(coordinatorDoc.getReshardingUUID(),
ChunkRange{reshardedChunk.getMin(), reshardedChunk.getMax()},
version,
reshardedChunk.getRecipientShardId());
version.incMinor();
}
} else {
int numInitialChunks = coordinatorDoc.getNumInitialChunks()
? *coordinatorDoc.getNumInitialChunks()
: cm.numChunks();
ShardKeyPattern shardKey(coordinatorDoc.getReshardingKey());
const auto tempNs = coordinatorDoc.getTempReshardingNss();
boost::optional<std::vector<mongo::TagsType>> parsedZones;
auto rawBSONZones = coordinatorDoc.getZones();
if (rawBSONZones && rawBSONZones->size() != 0) {
parsedZones.emplace();
parsedZones->reserve(rawBSONZones->size());
for (const auto& zone : *rawBSONZones) {
ChunkRange range(zone.getMin(), zone.getMax());
TagsType tag(
coordinatorDoc.getTempReshardingNss(), zone.getZone().toString(), range);
parsedZones->push_back(tag);
}
}
auto initialSplitter = ReshardingSplitPolicy::make(opCtx,
coordinatorDoc.getSourceNss(),
tempNs,
shardKey,
numInitialChunks,
std::move(parsedZones));
// Note: The resharding initial split policy doesn't care about what is the real primary
// shard, so just pass in a random shard.
const SplitPolicyParams splitParams{coordinatorDoc.getReshardingUUID(),
*donorShardIds.begin()};
auto splitResult = initialSplitter.createFirstChunks(opCtx, shardKey, splitParams);
initialChunks = std::move(splitResult.chunks);
for (const auto& chunk : initialChunks) {
recipientShardIds.insert(chunk.getShard());
}
}
return {constructDonorShardEntries(donorShardIds),
constructRecipientShardEntries(recipientShardIds),
initialChunks};
}
void ReshardingCoordinatorExternalStateImpl::sendCommandToShards(
OperationContext* opCtx,
StringData dbName,
const BSONObj& command,
const std::vector<ShardId>& shardIds,
const std::shared_ptr<executor::TaskExecutor>& executor) {
sharding_ddl_util::sendAuthenticatedCommandToShards(opCtx, dbName, command, shardIds, executor);
}
ThreadPool::Limits ReshardingCoordinatorService::getThreadPoolLimits() const {
ThreadPool::Limits threadPoolLimit;
threadPoolLimit.maxThreads = resharding::gReshardingCoordinatorServiceMaxThreadCount;
return threadPoolLimit;
}
std::shared_ptr<repl::PrimaryOnlyService::Instance> ReshardingCoordinatorService::constructInstance(
BSONObj initialState) {
return std::make_shared<ReshardingCoordinator>(
this,
ReshardingCoordinatorDocument::parse(IDLParserErrorContext("ReshardingCoordinatorStateDoc"),
std::move(initialState)),
std::make_shared<ReshardingCoordinatorExternalStateImpl>(),
_serviceContext);
}
ExecutorFuture<void> ReshardingCoordinatorService::_rebuildService(
std::shared_ptr<executor::ScopedTaskExecutor> executor, const CancellationToken& token) {
return AsyncTry([this] {
auto nss = getStateDocumentsNS();
AllowOpCtxWhenServiceRebuildingBlock allowOpCtxBlock(Client::getCurrent());
auto opCtxHolder = cc().makeOperationContext();
auto opCtx = opCtxHolder.get();
DBDirectClient client(opCtx);
BSONObj result;
client.runCommand(
nss.db().toString(),