mongo/jstests/parallel/insert.js

// perform inserts in parallel from several clients
load('jstests/libs/parallelTester.js');

f = db.jstests_parallel_insert;
f.drop();
f.ensureIndex({who: 1});

Random.setRandomSeed();

t = new ParallelTester();

for (id = 0; id < 10; ++id) {
    var g = new EventGenerator(id, "jstests_parallel_insert", Random.randInt(20));
    for (j = 0; j < 1000; ++j) {
        if (j % 50 == 0) {
            g.addCheckCount(j, {who: id});
        }
        g.addInsert({i: j, who: id});
    }
    t.add(EventGenerator.dispatch, g.getEvents());
}

t.run("one or more tests failed");

assert(f.validate().valid);