--- a/test/jdk/java/util/concurrent/tck/LongAccumulatorTest.java	Sat Sep 14 11:26:26 2019 -0700
+++ b/test/jdk/java/util/concurrent/tck/LongAccumulatorTest.java	Sat Sep 14 11:26:26 2019 -0700
@@ -150,7 +150,7 @@
             = new LongAccumulator((x, y) -> x + y, 0L);
         final int nThreads = ThreadLocalRandom.current().nextInt(1, 5);
         final Phaser phaser = new Phaser(nThreads + 1);
-        final int incs = 1_000_000;
+        final int incs = expensiveTests ? 1_000_000 : 100_000;
         final long total = nThreads * incs/2L * (incs - 1); // Gauss
         final Runnable task = () -> {
             phaser.arriveAndAwaitAdvance();