1066     vm_exit_during_initialization(
1067       "Incompatible compilation policy selected", NULL);
1068   }
1069   // Increase the code cache size - tiered compiles a lot more.
1070   if (FLAG_IS_DEFAULT(ReservedCodeCacheSize)) {
1071     FLAG_SET_DEFAULT(ReservedCodeCacheSize, ReservedCodeCacheSize * 2);
1072   }
1073 }
1074 
1075 #if INCLUDE_ALTERNATE_GCS
1076 static void disable_adaptive_size_policy(const char* collector_name) {
1077   if (UseAdaptiveSizePolicy) {
1078     if (FLAG_IS_CMDLINE(UseAdaptiveSizePolicy)) {
1079       warning("disabling UseAdaptiveSizePolicy; it is incompatible with %s.",
1080               collector_name);
1081     }
1082     FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
1083   }
1084 }
1085 
1086 // If the user has chosen ParallelGCThreads > 0, we set UseParNewGC
1087 // if it's not explictly set or unset. If the user has chosen
1088 // UseParNewGC and not explicitly set ParallelGCThreads we
1089 // set it, unless this is a single cpu machine.
1090 void Arguments::set_parnew_gc_flags() {
1091   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC && !UseG1GC,
1092          "control point invariant");
1093   assert(UseParNewGC, "Error");
1094 
1095   // Turn off AdaptiveSizePolicy for parnew until it is complete.
1096   disable_adaptive_size_policy("UseParNewGC");
1097 
1098   if (ParallelGCThreads == 0) {
1099     FLAG_SET_DEFAULT(ParallelGCThreads,
1100                      Abstract_VM_Version::parallel_worker_threads());
1101     if (ParallelGCThreads == 1) {
1102       FLAG_SET_DEFAULT(UseParNewGC, false);
1103       FLAG_SET_DEFAULT(ParallelGCThreads, 0);
1104     }
1105   }

1106   if (UseParNewGC) {
1107     // By default YoungPLABSize and OldPLABSize are set to 4096 and 1024 respectively,
1108     // these settings are default for Parallel Scavenger. For ParNew+Tenured configuration
1109     // we set them to 1024 and 1024.
1110     // See CR 6362902.
1111     if (FLAG_IS_DEFAULT(YoungPLABSize)) {
1112       FLAG_SET_DEFAULT(YoungPLABSize, (intx)1024);
1113     }
1114     if (FLAG_IS_DEFAULT(OldPLABSize)) {
1115       FLAG_SET_DEFAULT(OldPLABSize, (intx)1024);
1116     }
1117 
1118     // AlwaysTenure flag should make ParNew promote all at first collection.
1119     // See CR 6362902.
1120     if (AlwaysTenure) {
1121       FLAG_SET_CMDLINE(uintx, MaxTenuringThreshold, 0);
1122     }
1123     // When using compressed oops, we use local overflow stacks,
1124     // rather than using a global overflow list chained through
1125     // the klass word of the object's pre-image.

1066     vm_exit_during_initialization(
1067       "Incompatible compilation policy selected", NULL);
1068   }
1069   // Increase the code cache size - tiered compiles a lot more.
1070   if (FLAG_IS_DEFAULT(ReservedCodeCacheSize)) {
1071     FLAG_SET_DEFAULT(ReservedCodeCacheSize, ReservedCodeCacheSize * 2);
1072   }
1073 }
1074 
1075 #if INCLUDE_ALTERNATE_GCS
1076 static void disable_adaptive_size_policy(const char* collector_name) {
1077   if (UseAdaptiveSizePolicy) {
1078     if (FLAG_IS_CMDLINE(UseAdaptiveSizePolicy)) {
1079       warning("disabling UseAdaptiveSizePolicy; it is incompatible with %s.",
1080               collector_name);
1081     }
1082     FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
1083   }
1084 }
1085 




1086 void Arguments::set_parnew_gc_flags() {
1087   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC && !UseG1GC,
1088          "control point invariant");
1089   assert(UseParNewGC, "Error");
1090 
1091   // Turn off AdaptiveSizePolicy for parnew until it is complete.
1092   disable_adaptive_size_policy("UseParNewGC");
1093 
1094   if (FLAG_IS_DEFAULT(ParallelGCThreads)) {
1095     assert(ParallelGCThreads == 0, "Default value for ParallelGCThreads should be 0");
1096     uint par_gc_threads = Abstract_VM_Version::parallel_worker_threads();
1097     if (par_gc_threads > 1) {
1098       FLAG_SET_DEFAULT(ParallelGCThreads, par_gc_threads);

1099     }
1100   }
1101 
1102   if (UseParNewGC) {
1103     // By default YoungPLABSize and OldPLABSize are set to 4096 and 1024 respectively,
1104     // these settings are default for Parallel Scavenger. For ParNew+Tenured configuration
1105     // we set them to 1024 and 1024.
1106     // See CR 6362902.
1107     if (FLAG_IS_DEFAULT(YoungPLABSize)) {
1108       FLAG_SET_DEFAULT(YoungPLABSize, (intx)1024);
1109     }
1110     if (FLAG_IS_DEFAULT(OldPLABSize)) {
1111       FLAG_SET_DEFAULT(OldPLABSize, (intx)1024);
1112     }
1113 
1114     // AlwaysTenure flag should make ParNew promote all at first collection.
1115     // See CR 6362902.
1116     if (AlwaysTenure) {
1117       FLAG_SET_CMDLINE(uintx, MaxTenuringThreshold, 0);
1118     }
1119     // When using compressed oops, we use local overflow stacks,
1120     // rather than using a global overflow list chained through
1121     // the klass word of the object's pre-image.