diff options
Diffstat (limited to 'jstests/replsets')
-rw-r--r-- | jstests/replsets/query_with_txn_prepared.js | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/jstests/replsets/query_with_txn_prepared.js b/jstests/replsets/query_with_txn_prepared.js new file mode 100644 index 00000000000..fcf05002310 --- /dev/null +++ b/jstests/replsets/query_with_txn_prepared.js @@ -0,0 +1,63 @@ +/** + * This test attempts to reproduce the bug described in SERVER-48002. This is a best-effort test + * that will not detect this bug on every run, even if a bug exists. + * + * Snapshot isolation cannot be guaranteed for operations that ignore prepare conflicts. + * This means that two reads of the same record in the same snapshot can return different results. + * In practice, the DataCorruptionDetected assertion added by SERVER-40620 will trigger if an index + * points to a non-existent record. + * + * Queries that ignore prepare conflicts and use an index to satisfy a read can read a key from an + * index and fetch a record that appears to go missing within the same snapshot. This may happen + * when the collection read races with a prepared transaction that commits and deletes the record. + * + * + * @tags: [ + * uses_prepare_transaction, + * uses_transactions, + * ] + */ +(function() { +"use strict"; + +const replTest = new ReplSetTest({nodes: 2}); +replTest.startSet(); +replTest.initiate(); + +const primary = replTest.getPrimary(); +const dbName = "query_with_txn_prepared"; +const collName = "coll"; + +assert.commandWorked(primary.getDB(dbName)[collName].createIndexes([{x: 1}])); + +const transactionShell = startParallelShell(function() { + load("jstests/core/txns/libs/prepare_helpers.js"); // For PrepareHelpers. + + while (db.getSiblingDB("query_with_txn_prepared")["stopQueries"].find().count() == 0) { + for (let i = 0; i < 100; ++i) { + const session = db.getMongo().startSession(); + const sessionColl = session.getDatabase("query_with_txn_prepared")["coll"]; + + session.startTransaction({readConcern: {level: "majority"}}); + if (Math.random() < 0.5) { + assert.commandWorked(sessionColl.update({x: 1}, {x: 1}, {upsert: true})); + } else { + assert.commandWorked(sessionColl.remove({x: 1})); + } + + const prepareTimestamp = PrepareHelpers.prepareTransaction(session); + assert.commandWorked(PrepareHelpers.commitTransaction(session, prepareTimestamp)); + } + } +}, primary.port); + +for (let i = 0; i < 2000; ++i) { + const result = primary.getDB(dbName)[collName].find({x: 1}).toArray(); + assert([0, 1].includes(result.length), result); +} + +assert.commandWorked(primary.getDB(dbName)["stopQueries"].insert({stop: 1})); +transactionShell(); + +replTest.stopSet(); +}()); |