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/**
* Tests that an initial sync that starts in the middle of a large transaction on a secondary
* is able to complete and apply the entire transaction.
*
* @tags: [
* exclude_from_large_txns,
* uses_transactions,
* ]
*/
(function() {
"use strict";
load("jstests/replsets/rslib.js"); // For reconnect()
load("jstests/libs/fail_point_util.js");
const replTest = new ReplSetTest({
nodes: [{}, {rsConfig: {priority: 0}}],
nodeOptions: {
setParameter:
// We want two entries in each oplog batch, so the beginning of the transaction is not
// the end of the batch.
{maxNumberOfTransactionOperationsInSingleOplogEntry: 1, bgSyncOplogFetcherBatchSize: 2}
},
});
replTest.startSet();
replTest.initiateWithHighElectionTimeout();
// We have to add and pause the initial sync node here, because we cannot re-initiate the set while
// the failpoints are held.
jsTestLog("Adding initial sync node");
const initialSyncNode = replTest.add({
rsConfig: {priority: 0, votes: 0},
setParameter: {
'initialSyncSourceReadPreference': 'secondary',
'failpoint.initialSyncHangBeforeChoosingSyncSource': tojson({mode: 'alwaysOn'}),
'logComponentVerbosity': tojsononeline({replication: {initialSync: 1}})
}
});
replTest.reInitiate();
const dbName = jsTest.name();
const collName = "coll";
const primary = replTest.getPrimary();
const testDB = primary.getDB(dbName);
const syncSource = replTest.nodes[1];
assert.commandWorked(testDB.runCommand({create: collName, writeConcern: {w: "majority"}}));
jsTest.log("Stop secondary oplog replication before the last operation in the transaction.");
// The stopReplProducerOnDocument failpoint ensures that secondary stops replicating before
// accepting the last two operations in the transaction.
const stopReplProducerOnDocumentFailPoint = configureFailPoint(
syncSource, "stopReplProducerOnDocument", {document: {"applyOps.o._id": "next-last in txn"}});
// This will cause us to pause batch application at a critical point, with "first in txn" and
// "next in txn" in the oplog but not applied.
const pauseBatchApplicationAfterWritingOplogEntriesFailPoint =
configureFailPoint(syncSource, "pauseBatchApplicationAfterWritingOplogEntries");
jsTestLog("Starting transaction");
const session = primary.startSession({causalConsistency: false});
const sessionDB = session.getDatabase(dbName);
session.startTransaction({writeConcern: {w: 1}});
assert.commandWorked(sessionDB.getCollection(collName).insert({_id: "first in txn"}));
assert.commandWorked(sessionDB.getCollection(collName).insert({_id: "next in txn"}));
assert.commandWorked(sessionDB.getCollection(collName).insert({_id: "next-last in txn"}));
assert.commandWorked(sessionDB.getCollection(collName).insert({_id: "last in txn"}));
jsTestLog("Committing transaction");
assert.commandWorked(session.commitTransaction_forTesting());
stopReplProducerOnDocumentFailPoint.wait();
pauseBatchApplicationAfterWritingOplogEntriesFailPoint.wait();
jsTestLog("Starting initial sync");
assert.commandWorked(initialSyncNode.adminCommand(
{configureFailPoint: "initialSyncHangBeforeChoosingSyncSource", mode: "off"}));
// The bug we're testing for is a race. The way we fix the race is to wait until it resolves.
// So it's very difficult to test it deterministically; if we use failpoints to force the race to
// happen, we'll just hang when the code is correct. Instead we hold the sync source in the
// condition that causes the race until we reach the point it's about to happen, then release
// it hoping it'll fail most of the time when the bug is present.
jsTestLog("Waiting to fetch the defaultBeginFetchingOplogEntry");
checkLog.containsJson(initialSyncNode, 6608900);
stopReplProducerOnDocumentFailPoint.off();
pauseBatchApplicationAfterWritingOplogEntriesFailPoint.off();
replTest.awaitSecondaryNodes();
replTest.awaitReplication();
// Make sure we got the transaction.
assert.eq(4, initialSyncNode.getDB(dbName)[collName].find().itcount());
printjson(initialSyncNode.getDB("local").oplog.rs.find().toArray());
replTest.stopSet();
})();
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