diff options
| -rw-r--r-- | src/mongo/db/s/shard_filtering_metadata_refresh.cpp | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/src/mongo/db/s/shard_filtering_metadata_refresh.cpp b/src/mongo/db/s/shard_filtering_metadata_refresh.cpp index 67aac77d941..c9270415e48 100644 --- a/src/mongo/db/s/shard_filtering_metadata_refresh.cpp +++ b/src/mongo/db/s/shard_filtering_metadata_refresh.cpp @@ -133,6 +133,24 @@ Status refreshDbMetadata(OperationContext* opCtx, const auto swDbMetadata = Grid::get(opCtx)->catalogCache()->getDatabaseWithRefresh(opCtx, dbName.db()); + // Before setting the database metadata, exit early if the database version received by the + // config server is not newer than the cached one. This is a best-effort optimization to reduce + // the number of possible threads convoying on the exclusive lock below. + { + Lock::DBLock dbLock(opCtx, dbName, MODE_IS); + const auto cachedDbVersion = DatabaseHolder::get(opCtx)->getDbVersion(opCtx, dbName); + if (swDbMetadata.isOK() && swDbMetadata.getValue()->getVersion() <= cachedDbVersion) { + LOGV2_DEBUG(7079300, + 2, + "Skip setting cached database metadata as there are no updates", + "db"_attr = dbName, + "cachedDbVersion"_attr = *cachedDbVersion, + "refreshedDbVersion"_attr = swDbMetadata.getValue()->getVersion()); + + return Status::OK(); + } + } + Lock::DBLock dbLock(opCtx, dbName, MODE_X); auto* dss = DatabaseShardingState::get(opCtx, dbName.db()); const auto dssLock = DatabaseShardingState::DSSLock::lockExclusive(opCtx, dss); |