lib/runners/base_runner.js
function () {
    var memory = Math.round(process.memoryUsage().rss / (1024 * 1024));

    if (!this.memoryWarning && memory > this.getMaxMemory()) {
      this.memoryWarning = true;
      console.log("\nWarning! Memory usage exceeded " + this.getMaxMemory() + 'MB for test suite ' +
        process.env.WORKER_TEST + '. ' +
        'Please split these tests into smaller suites.');
    }
  }
function () {
    var memory = Math.round(process.memoryUsage().rss / (1024 * 1024));

    if (!this.memoryWarning && memory > this.getMaxMemory()) {
      this.memoryWarning = true;
      console.log("\nWarning! Memory usage exceeded " + this.getMaxMemory() + 'MB for test suite ' +
        process.env.WORKER_TEST + '. ' +
        'Please split these tests into smaller suites.');
    }
  }
BaseRunner.checkMemory()