1673     if (FLAG_IS_DEFAULT(MinSurvivorRatio)) {
1674       FLAG_SET_DEFAULT(MinSurvivorRatio, SurvivorRatio + 2);
1675     }
1676   }
1677 
1678   if (UseParallelOldGC) {
1679     // Par compact uses lower default values since they are treated as
1680     // minimums.  These are different defaults because of the different
1681     // interpretation and are not ergonomically set.
1682     if (FLAG_IS_DEFAULT(MarkSweepDeadRatio)) {
1683       FLAG_SET_DEFAULT(MarkSweepDeadRatio, 1);
1684     }
1685   }
1686 }
1687 
1688 void Arguments::set_g1_gc_flags() {
1689   assert(UseG1GC, "Error");
1690 #ifdef COMPILER1
1691   FastTLABRefill = false;
1692 #endif
1693   FLAG_SET_DEFAULT(ParallelGCThreads,
1694                      Abstract_VM_Version::parallel_worker_threads());
1695   if (ParallelGCThreads == 0) {
1696     FLAG_SET_DEFAULT(ParallelGCThreads,
1697                      Abstract_VM_Version::parallel_worker_threads());
1698   }
1699 
1700 #if INCLUDE_ALL_GCS
1701   if (G1ConcRefinementThreads == 0) {
1702     FLAG_SET_DEFAULT(G1ConcRefinementThreads, ParallelGCThreads);
1703   }
1704 #endif
1705 
1706   // MarkStackSize will be set (if it hasn't been set by the user)
1707   // when concurrent marking is initialized.
1708   // Its value will be based upon the number of parallel marking threads.
1709   // But we do set the maximum mark stack size here.
1710   if (FLAG_IS_DEFAULT(MarkStackSizeMax)) {
1711     FLAG_SET_DEFAULT(MarkStackSizeMax, 128 * TASKQUEUE_SIZE);
1712   }
1713 
1714   if (FLAG_IS_DEFAULT(GCTimeRatio) || GCTimeRatio == 0) {
1715     // In G1, we want the default GC overhead goal to be higher than
1716     // say in PS. So we set it here to 10%. Otherwise the heap might
1717     // be expanded more aggressively than we would like it to. In

1673     if (FLAG_IS_DEFAULT(MinSurvivorRatio)) {
1674       FLAG_SET_DEFAULT(MinSurvivorRatio, SurvivorRatio + 2);
1675     }
1676   }
1677 
1678   if (UseParallelOldGC) {
1679     // Par compact uses lower default values since they are treated as
1680     // minimums.  These are different defaults because of the different
1681     // interpretation and are not ergonomically set.
1682     if (FLAG_IS_DEFAULT(MarkSweepDeadRatio)) {
1683       FLAG_SET_DEFAULT(MarkSweepDeadRatio, 1);
1684     }
1685   }
1686 }
1687 
1688 void Arguments::set_g1_gc_flags() {
1689   assert(UseG1GC, "Error");
1690 #ifdef COMPILER1
1691   FastTLABRefill = false;
1692 #endif
1693   FLAG_SET_DEFAULT(ParallelGCThreads, Abstract_VM_Version::parallel_worker_threads());

1694   if (ParallelGCThreads == 0) {
1695     assert(!FLAG_IS_DEFAULT(ParallelGCThreads), "The default value for ParallelGCThreads should not be 0.");
1696     vm_exit_during_initialization("The G1 GC can not be combined with -XX:ParallelGCThreads=0", NULL);
1697   }
1698 
1699 #if INCLUDE_ALL_GCS
1700   if (G1ConcRefinementThreads == 0) {
1701     FLAG_SET_DEFAULT(G1ConcRefinementThreads, ParallelGCThreads);
1702   }
1703 #endif
1704 
1705   // MarkStackSize will be set (if it hasn't been set by the user)
1706   // when concurrent marking is initialized.
1707   // Its value will be based upon the number of parallel marking threads.
1708   // But we do set the maximum mark stack size here.
1709   if (FLAG_IS_DEFAULT(MarkStackSizeMax)) {
1710     FLAG_SET_DEFAULT(MarkStackSizeMax, 128 * TASKQUEUE_SIZE);
1711   }
1712 
1713   if (FLAG_IS_DEFAULT(GCTimeRatio) || GCTimeRatio == 0) {
1714     // In G1, we want the default GC overhead goal to be higher than
1715     // say in PS. So we set it here to 10%. Otherwise the heap might
1716     // be expanded more aggressively than we would like it to. In