159         Asserts.assertTrue(getWhiteBox().isObjectInOldGen(toUnreachable), "List of the objects is suppose to be in OldGen");
 160     }
 161 
 162     private static void waitTillCMCFinished(int sleepTime) {
 163         while (getWhiteBox().g1InConcurrentMark()) {
 164               try {sleep(sleepTime);} catch (Exception e) {}
 165         }
 166     }
 167 
 168     /**
 169     * The necessary condition for guaranteed mixed GC is running in VM with the following flags:
 170     * -XX:+UnlockExperimentalVMOptions -XX:+AlwaysTenure -Xms{HEAP_SIZE}M
 171     * -Xmx{HEAP_SIZE}M -XX:G1MixedGCLiveThresholdPercent=100 -XX:G1HeapWastePercent=0
 172     * -XX:G1HeapRegionSize={REGION_SIZE}m
 173     *
 174     * @param g1HeapRegionSize The size of your regions in bytes
 175     */
 176     public static void provokeMixedGC(int g1HeapRegionSize) {
 177         final var arraySize = 20_000;
 178         var liveOldObjects = new ArrayList<byte[]>();



 179         allocateOldObjects(liveOldObjects, g1HeapRegionSize, arraySize);
 180         waitTillCMCFinished(10);
 181         getWhiteBox().g1StartConcMarkCycle();
 182         waitTillCMCFinished(10);
 183         getWhiteBox().youngGC();
 184         getWhiteBox().youngGC();
 185 
 186         // check that liveOldObjects still alive
 187         assertTrue(getWhiteBox().isObjectInOldGen(liveOldObjects), "List of the objects is suppose to be in OldGen");
 188     }
 189 }

 159         Asserts.assertTrue(getWhiteBox().isObjectInOldGen(toUnreachable), "List of the objects is suppose to be in OldGen");
 160     }
 161 
 162     private static void waitTillCMCFinished(int sleepTime) {
 163         while (getWhiteBox().g1InConcurrentMark()) {
 164               try {sleep(sleepTime);} catch (Exception e) {}
 165         }
 166     }
 167 
 168     /**
 169     * The necessary condition for guaranteed mixed GC is running in VM with the following flags:
 170     * -XX:+UnlockExperimentalVMOptions -XX:+AlwaysTenure -Xms{HEAP_SIZE}M
 171     * -Xmx{HEAP_SIZE}M -XX:G1MixedGCLiveThresholdPercent=100 -XX:G1HeapWastePercent=0
 172     * -XX:G1HeapRegionSize={REGION_SIZE}m
 173     *
 174     * @param g1HeapRegionSize The size of your regions in bytes
 175     */
 176     public static void provokeMixedGC(int g1HeapRegionSize) {
 177         final var arraySize = 20_000;
 178         var liveOldObjects = new ArrayList<byte[]>();
 179 
 180         // Make sure the heap is in a known state.
 181         getWhiteBox().fullGC();
 182         allocateOldObjects(liveOldObjects, g1HeapRegionSize, arraySize);
 183         waitTillCMCFinished(10);
 184         getWhiteBox().g1StartConcMarkCycle();
 185         waitTillCMCFinished(10);
 186         getWhiteBox().youngGC();
 187         getWhiteBox().youngGC();
 188 
 189         // check that liveOldObjects still alive
 190         assertTrue(getWhiteBox().isObjectInOldGen(liveOldObjects), "List of the objects is suppose to be in OldGen");
 191     }
 192 }