47             checkMemoryUsage("Compressed Class Space", "sun.gc.compressedclassspace");
  48         }
  49     }
  50 
  51     private static MemoryPoolMXBean getMemoryPool(String memoryPoolName) {
  52         List<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans();
  53         for (MemoryPoolMXBean pool : pools) {
  54             if (pool.getName().equals(memoryPoolName)) {
  55                 return pool;
  56             }
  57         }
  58 
  59         throw new RuntimeException("Excpted to find a memory pool with name " +
  60                                    memoryPoolName);
  61     }
  62 
  63     private static void checkMemoryUsage(String memoryPoolName, String perfNS)
  64         throws Exception {
  65         MemoryPoolMXBean pool = getMemoryPool(memoryPoolName);
  66 









  67         // Must do a GC to update performance counters
  68         System.gc();
  69         assertEQ(getMinCapacity(perfNS), pool.getUsage().getInit());
  70 
  71         // Must do a second GC to update the perfomance counters again, since
  72         // the call pool.getUsage().getInit() could have allocated some
  73         // metadata.
  74         System.gc();
  75         assertEQ(getUsed(perfNS), pool.getUsage().getUsed());
  76         assertEQ(getCapacity(perfNS), pool.getUsage().getCommitted());
  77     }
  78 
  79     private static long getMinCapacity(String ns) throws Exception {
  80         return PerfCounters.findByName(ns + ".minCapacity").longValue();
  81     }
  82 
  83     private static long getCapacity(String ns) throws Exception {
  84         return PerfCounters.findByName(ns + ".capacity").longValue();
  85     }
  86 
  87     private static long getUsed(String ns) throws Exception {
  88         return PerfCounters.findByName(ns + ".used").longValue();
  89     }
  90 }

  47             checkMemoryUsage("Compressed Class Space", "sun.gc.compressedclassspace");
  48         }
  49     }
  50 
  51     private static MemoryPoolMXBean getMemoryPool(String memoryPoolName) {
  52         List<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans();
  53         for (MemoryPoolMXBean pool : pools) {
  54             if (pool.getName().equals(memoryPoolName)) {
  55                 return pool;
  56             }
  57         }
  58 
  59         throw new RuntimeException("Excpted to find a memory pool with name " +
  60                                    memoryPoolName);
  61     }
  62 
  63     private static void checkMemoryUsage(String memoryPoolName, String perfNS)
  64         throws Exception {
  65         MemoryPoolMXBean pool = getMemoryPool(memoryPoolName);
  66 
  67         // First, call all the methods to let them allocate their own slab of metadata
  68         getMinCapacity(perfNS);
  69         getCapacity(perfNS);
  70         getUsed(perfNS);
  71         pool.getUsage().getInit();
  72         pool.getUsage().getUsed();
  73         pool.getUsage().getCommitted();
  74         assertEQ(1L, 1L);
  75 
  76         // Must do a GC to update performance counters
  77         System.gc();
  78         assertEQ(getMinCapacity(perfNS), pool.getUsage().getInit());





  79         assertEQ(getUsed(perfNS), pool.getUsage().getUsed());
  80         assertEQ(getCapacity(perfNS), pool.getUsage().getCommitted());
  81     }
  82 
  83     private static long getMinCapacity(String ns) throws Exception {
  84         return PerfCounters.findByName(ns + ".minCapacity").longValue();
  85     }
  86 
  87     private static long getCapacity(String ns) throws Exception {
  88         return PerfCounters.findByName(ns + ".capacity").longValue();
  89     }
  90 
  91     private static long getUsed(String ns) throws Exception {
  92         return PerfCounters.findByName(ns + ".used").longValue();
  93     }
  94 }