--- /dev/null 2018-06-10 19:57:01.244702788 +0200 +++ new/test/hotspot/jtreg/gc/epsilon/TestManyThreads.java 2018-06-11 09:34:22.823029730 +0200 @@ -0,0 +1,79 @@ +/* + * Copyright (c) 2017, 2018, Red Hat, Inc. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +/** + * @test TestManyThreads + * @key gc + * @requires vm.gc.Epsilon + * @summary Test allocations from many threads + * + * @run main/othervm -Xmx128m -Xss512k -XX:-UseTLAB -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC TestManyThreads + * @run main/othervm -Xmx128m -Xss512k -Xint -XX:-UseTLAB -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC TestManyThreads + * @run main/othervm -Xmx128m -Xss512k -Xbatch -Xcomp -XX:-UseTLAB -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC TestManyThreads + * @run main/othervm -Xmx128m -Xss512k -Xbatch -Xcomp -XX:TieredStopAtLevel=1 -XX:-UseTLAB -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC TestManyThreads + * @run main/othervm -Xmx128m -Xss512k -Xbatch -Xcomp -XX:-TieredCompilation -XX:-UseTLAB -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC TestManyThreads + * + * @run main/othervm -Xmx128m -Xss512k -XX:+UseTLAB -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC TestManyThreads + * @run main/othervm -Xmx128m -Xss512k -Xint -XX:+UseTLAB -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC TestManyThreads + * @run main/othervm -Xmx128m -Xss512k -Xbatch -Xcomp -XX:+UseTLAB -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC TestManyThreads + * @run main/othervm -Xmx128m -Xss512k -Xbatch -Xcomp -XX:TieredStopAtLevel=1 -XX:+UseTLAB -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC TestManyThreads + * @run main/othervm -Xmx128m -Xss512k -Xbatch -Xcomp -XX:-TieredCompilation -XX:+UseTLAB -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC TestManyThreads + */ + +import java.util.concurrent.atomic.*; + +public class TestManyThreads { + + static int COUNT = Integer.getInteger("count", 128); // 128 * 4M max tlabs = 512M, would overflow without TLAB sizing + + static volatile Object sink; + static volatile Throwable failed; + static final AtomicInteger allocated = new AtomicInteger(); + + public static void workload() { + try { + sink = new Object(); + allocated.incrementAndGet(); + Thread.sleep(3600 * 1000); + } catch (Throwable e) { + failed = e; + } + } + + public static void main(String[] args) throws Throwable { + for (int c = 0; c < COUNT; c++) { + Thread t = new Thread(TestManyThreads::workload); + t.setDaemon(true); + t.start(); + } + + while ((failed == null) && (allocated.get() != COUNT)) { + Thread.sleep(100); + } + + if (failed != null) { + throw failed; + } + } + +}