test/jdk/sun/management/HotspotRuntimeMBean/GetSafepointSyncTime.java

*** 1,7 ****
  /*
!  * Copyright (c) 2003, 2015, Oracle and/or its affiliates. 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.
--- 1,7 ----
  /*
!  * Copyright (c) 2003, 2018, Oracle and/or its affiliates. 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.
*** 21,31 ****
   * questions.
   */
  
  /*
   * @test
!  * @bug     4858522
   * @summary Basic unit test of HotspotRuntimeMBean.getSafepointSyncTime()
   * @author  Steve Bohne
   *
   * @run main/othervm -XX:+UsePerfData GetSafepointSyncTime
   */
--- 21,31 ----
   * questions.
   */
  
  /*
   * @test
!  * @bug     4858522 8174734
   * @summary Basic unit test of HotspotRuntimeMBean.getSafepointSyncTime()
   * @author  Steve Bohne
   *
   * @run main/othervm -XX:+UsePerfData GetSafepointSyncTime
   */
*** 41,93 ****
      private static HotspotRuntimeMBean mbean =
          (HotspotRuntimeMBean)ManagementFactoryHelper.getHotspotRuntimeMBean();
  
      private static final long NUM_THREAD_DUMPS = 300;
  
!     // Careful with these values.
!     private static final long MIN_VALUE_FOR_PASS = 1;
!     private static final long MAX_VALUE_FOR_PASS = Long.MAX_VALUE;
  
      public static void main(String args[]) throws Exception {
          long count = mbean.getSafepointCount();
!         long value = mbean.getSafepointSyncTime();
  
-         // Thread.getAllStackTraces() should cause safepoints.
-         // If this test is failing because it doesn't,
-         // MIN_VALUE_FOR_PASS should be reset to 0
          for (int i = 0; i < NUM_THREAD_DUMPS; i++) {
              Thread.getAllStackTraces();
          }
  
          long count1 = mbean.getSafepointCount();
!         long value1 = mbean.getSafepointSyncTime();
  
!         System.out.format("Safepoint count=%d (diff=%d), sync time=%d ms (diff=%d)%n",
!                           count1, count1-count, value1, value1-value);
  
!         if (value1 < MIN_VALUE_FOR_PASS || value1 > MAX_VALUE_FOR_PASS) {
!             throw new RuntimeException("Safepoint sync time " +
!                                        "illegal value: " + value1 + " ms " +
!                                        "(MIN = " + MIN_VALUE_FOR_PASS + "; " +
!                                        "MAX = " + MAX_VALUE_FOR_PASS + ")");
!         }
  
          for (int i = 0; i < NUM_THREAD_DUMPS; i++) {
              Thread.getAllStackTraces();
          }
  
          long count2 = mbean.getSafepointCount();
!         long value2 = mbean.getSafepointSyncTime();
! 
!         System.out.format("Safepoint count=%d (diff=%d), sync time=%d ms (diff=%d)%n",
!                           count2, count2-count1, value2, value2-value1);
  
!         if (value2 <= value1) {
!             throw new RuntimeException("Safepoint sync time " +
!                                        "did not increase " +
!                                        "(value1 = " + value1 + "; " +
!                                        "value2 = " + value2 + ")");
!         }
  
          System.out.println("Test passed.");
      }
  }
--- 41,114 ----
      private static HotspotRuntimeMBean mbean =
          (HotspotRuntimeMBean)ManagementFactoryHelper.getHotspotRuntimeMBean();
  
      private static final long NUM_THREAD_DUMPS = 300;
  
!     static void checkPositive(long value, String label) {
!         if (value < 0)
!             throw new RuntimeException(label + " had a negative value of "
!                                        + value);
!     }
! 
!     static void validate(long count1, long count2, long time1, long time2,
!                          String label) {
!         checkPositive(count1, label + ":count1");
!         checkPositive(count2, label + ":count2");
!         checkPositive(time1, label + ":time1");
!         checkPositive(time2, label + ":time2");
! 
!         long countDiff = count2 - count1;
!         long timeDiff = time2 - time1;
! 
!         if (countDiff < NUM_THREAD_DUMPS) {
!             throw new RuntimeException(label +
!                                        ": Expected at least " + NUM_THREAD_DUMPS +
!                                        "safepoints but only got " + countDiff);
!         }
! 
!         // getSafepointSyncTime is the accumulated time spent getting to a
!         // safepoint, so each safepoint will add a little to this, but the
!         // resolution is only milliseconds so we may not see it.
!         if (timeDiff < 0) {
!             throw new RuntimeException(label + ": Safepoint sync time " +
!                                        "decreased unexpectedly " +
!                                        "(time1 = " + time1 + "; " +
!                                        "time2 = " + time2 + ")");
!         }
! 
!         System.out.format("%s: Safepoint count=%d (diff=%d), sync time=%d ms (diff=%d)%n",
!                           label, count2, countDiff, time2, timeDiff);
! 
!     }
  
      public static void main(String args[]) throws Exception {
          long count = mbean.getSafepointCount();
!         long time = mbean.getSafepointSyncTime();
! 
!         checkPositive(count, "count");
!         checkPositive(time, "time");
! 
!         // Thread.getAllStackTraces() should cause a safepoint.
  
          for (int i = 0; i < NUM_THREAD_DUMPS; i++) {
              Thread.getAllStackTraces();
          }
  
          long count1 = mbean.getSafepointCount();
!         long time1 = mbean.getSafepointSyncTime();
  
!         validate(count, count1, time, time1, "Pass 1");
  
!         // repeat the experiment
  
          for (int i = 0; i < NUM_THREAD_DUMPS; i++) {
              Thread.getAllStackTraces();
          }
  
          long count2 = mbean.getSafepointCount();
!         long time2 = mbean.getSafepointSyncTime();
  
!         validate(count1, count2, time1, time2, "Pass 2");
  
          System.out.println("Test passed.");
      }
  }