mongodb/jstests/noPassthrough/wt_cache_full_multi_oplog_txns.js

/**
 * Fills WiredTiger cache during steady state oplog application.
 * @tags: [requires_replication, requires_wiredtiger]
 */
(function() {
    'use strict';

    const rst = new ReplSetTest({
        nodes: [
            {
              slowms: 30000,  // Don't log slow operations on primary.
            },
            {
              // Disallow elections on secondary.
              rsConfig: {
                  priority: 0,
                  votes: 0,
              },
            },
        ],
        nodeOptions: {
            // Constrain the storage engine cache size to make it easier to fill it up with
            // unflushed modifications.
            wiredTigerCacheSizeGB: 1,
        },
    });
    const nodes = rst.startSet();
    rst.initiate();

    const primary = rst.getPrimary();
    const mydb = primary.getDB('test');
    const coll = mydb.getCollection('t');

    const numDocs = 2;
    const minDocSizeMB = 10;

    for (let i = 0; i < numDocs; ++i) {
        assert.writeOK(
            coll.save({_id: i, i: 0, x: 'x'.repeat(minDocSizeMB * 1024 * 1024)},
                      {writeConcern: {w: nodes.length, wtimeout: ReplSetTest.kDefaultTimeoutMS}}));
    }
    assert.eq(numDocs, coll.find().itcount());

    const numUpdates = 500;
    const secondary = rst.getSecondary();
    const batchOpsLimit =
        assert.commandWorked(secondary.adminCommand({getParameter: 1, replBatchLimitOperations: 1}))
            .replBatchLimitOperations;
    jsTestLog('Oplog application on secondary ' + secondary.host + ' is limited to ' +
              batchOpsLimit + ' operations per batch.');

    jsTestLog('Buffering ' + numUpdates + ' updates to ' + numDocs + ' documents on secondary.');
    const session = primary.startSession();
    const sessionDB = session.getDatabase(mydb.getName());
    const sessionColl = sessionDB.getCollection(coll.getName());
    session.startTransaction();
    for (let i = 0; i < numDocs; ++i) {
        for (let j = 0; j < numUpdates; ++j) {
            assert.writeOK(sessionColl.update({_id: i}, {$inc: {i: 1}}));
        }
    }
    assert.commandWorked(session.commitTransaction_forTesting());
    session.endSession();

    jsTestLog('Applying updates on secondary ' + secondary.host);

    // If the secondary is unable to apply all the operations in the unprepared transaction within
    // a single batch with the constrained cache settings, the replica set will not reach a stable
    // state.
    rst.awaitReplication();

    rst.stopSet();
})();