Minimal reproducer using only find() to demonstrate fast count updates from uncommitted transactions being leaked diff --git a/jstests/noPassthrough/repro.js b/jstests/noPassthrough/repro.js new file mode 100644 index 00000000000..d54c5e98a8e --- /dev/ null +++ b/jstests/noPassthrough/repro.js @@ -0,0 +1,42 @@ + import {configureFailPoint} from "jstests/libs/fail_point_util.js" ; + import {funWithArgs} from "jstests/libs/parallel_shell_helpers.js" ; + import {ReplSetTest} from "jstests/libs/replsettest.js" ; + +let rst = new ReplSetTest({ + name: jsTestName(), + nodes: 1, +}); +rst.startSet(); +rst.initiate(); +let primary = rst.getPrimary(); + +let db = primary.getDB( "test" ); +let coll = db.getCollection( "test" ); + + // Insert some data and check that fast count is correct. + for (let i = 0; i < 5; i++) { + assert .commandWorked(coll.insert({_id: i})); +} + + assert (coll.find().count() == 5); + assert (coll.find().itcount() == 5); + + // Begin a transaction, hang after notifying the WiredTigerSizeStorer of a change. +let fp = configureFailPoint(primary, "WTHangAfterFastCountUpdate" ); +let awaitInsert = + startParallelShell(funWithArgs(function(dbName, collName) { + assert .commandWorked(db.getSiblingDB(dbName)[collName].insert({_id: 5})); + }, db.getName(), coll.getName()), primary.port); +fp.wait(); + + assert (coll.find().count() == 6); // Should be 5 at this point. + assert (coll.find().itcount() == 5); + + // Commit the transaction. +fp.off(); +awaitInsert(); + + assert (coll.find().count() == 6); + assert (coll.find().itcount() == 6); + +rst.stopSet(); diff --git a/src/mongo/db/storage/wiredtiger/wiredtiger_record_store.cpp b/src/mongo/db/storage/wiredtiger/wiredtiger_record_store.cpp index bfa5b99b2ea..b9e0cd05556 100644 --- a/src/mongo/db/storage/wiredtiger/wiredtiger_record_store.cpp +++ b/src/mongo/db/storage/wiredtiger/wiredtiger_record_store.cpp @@ -216,6 +216,7 @@ MONGO_FAIL_POINT_DEFINE(WTCompactRecordStoreEBUSY); MONGO_FAIL_POINT_DEFINE(WTRecordStoreUassertOutOfOrder); MONGO_FAIL_POINT_DEFINE(WTWriteConflictException); MONGO_FAIL_POINT_DEFINE(WTWriteConflictExceptionForReads); +MONGO_FAIL_POINT_DEFINE(WTHangAfterFastCountUpdate); StatusWith<std::string> WiredTigerRecordStore::parseOptionsField( const BSONObj options) { StringBuilder ss; @@ -1033,6 +1034,10 @@ Status WiredTigerRecordStore::_insertRecords(OperationContext* opCtx, } _changeNumRecordsAndDataSize(opCtx, nRecords, totalLength); + if (MONGO_unlikely(WTHangAfterFastCountUpdate.shouldFail())) { + WTHangAfterFastCountUpdate.pauseWhileSet(opCtx); + } + if (_oplog && _oplog->getTruncateMarkers()) { // records[nRecords - 1] is the record in the oplog with the highest recordId. auto wall = [&] {