8204210: Implementation: JEP 333: ZGC: A Scalable Low-Latency Garbage Collector (Experimental)
Reviewed-by: pliden, stefank, eosterlund, ehelin, sjohanss, rbackman, coleenp, ihse, jgeorge, lmesnik, rkennke
Contributed-by: per.liden@oracle.com, stefan.karlsson@oracle.com, erik.osterlund@oracle.com, mikael.gerdin@oracle.com, kim.barrett@oracle.com, nils.eliasson@oracle.com, rickard.backman@oracle.com, rwestrel@redhat.com, coleen.phillimore@oracle.com, robbin.ehn@oracle.com, gerard.ziemski@oracle.com, hugh.wilkinson@intel.com, sandhya.viswanathan@intel.com, bill.npo.wheeler@intel.com, vinay.k.awasthi@intel.com, yasuenag@gmail.com
/*
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*
* This code is distributed in the hope that it will be useful, but WITHOUT
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* 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).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
import utils.*;
/*
* @test
* @summary Test checks output displayed with jstat -gcnew.
* Test scenario:
* test several times provokes garbage collection in the debuggee application and after each garbage
* collection runs jstat. jstat should show that after garbage collection number of GC events and garbage
* collection time increase.
* @requires vm.gc != "Z"
* @modules java.base/jdk.internal.misc
* @library /test/lib
* @library ../share
* @run main/othervm -XX:+UsePerfData -Xmx128M GcNewTest
*/
public class GcNewTest {
public static void main(String[] args) throws Exception {
// We will be running "jstat -gc" tool
JstatGcNewTool jstatGcTool = new JstatGcNewTool(ProcessHandle.current().pid());
// Run once and get the results asserting that they are reasonable
JstatGcNewResults measurement1 = jstatGcTool.measure();
measurement1.assertConsistency();
GcProvoker gcProvoker = new GcProvoker();
// Provoke GC and run the tool again
gcProvoker.provokeGc();
JstatGcNewResults measurement2 = jstatGcTool.measure();
measurement2.assertConsistency();
// Assert the increase in GC events and time between the measurements
assertThat(measurement2.getFloatValue("YGC") > measurement1.getFloatValue("YGC"), "YGC didn't increase between measurements 1 and 2");
assertThat(measurement2.getFloatValue("YGCT") > measurement1.getFloatValue("YGCT"), "YGCT time didn't increase between measurements 1 and 2");
// Provoke GC and run the tool again
gcProvoker.provokeGc();
JstatGcNewResults measurement3 = jstatGcTool.measure();
measurement3.assertConsistency();
// Assert the increase in GC events and time between the measurements
assertThat(measurement3.getFloatValue("YGC") > measurement2.getFloatValue("YGC"), "YGC didn't increase between measurements 1 and 2");
assertThat(measurement3.getFloatValue("YGCT") > measurement2.getFloatValue("YGCT"), "YGCT time didn't increase between measurements 1 and 2");
}
private static void assertThat(boolean result, String message) {
if (!result) {
throw new RuntimeException(message);
};
}
}