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src/hotspot/share/gc/shenandoah/shenandoahArguments.cpp

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 154   }
 155 
 156   // Record more information about previous cycles for improved debugging pleasure
 157   if (FLAG_IS_DEFAULT(LogEventsBufferEntries)) {
 158     FLAG_SET_DEFAULT(LogEventsBufferEntries, 250);
 159   }
 160 
 161   if (ShenandoahAlwaysPreTouch) {
 162     if (!FLAG_IS_DEFAULT(ShenandoahUncommit)) {
 163       warning("AlwaysPreTouch is enabled, disabling ShenandoahUncommit");
 164     }
 165     FLAG_SET_DEFAULT(ShenandoahUncommit, false);
 166   }
 167 
 168   if ((InitialHeapSize == MaxHeapSize) && ShenandoahUncommit) {
 169     log_info(gc)("Min heap equals to max heap, disabling ShenandoahUncommit");
 170     FLAG_SET_DEFAULT(ShenandoahUncommit, false);
 171   }
 172 
 173   // If class unloading is disabled, no unloading for concurrent cycles as well.
 174   // If class unloading is enabled, users should opt-in for unloading during
 175   // concurrent cycles.
 176   if (!ClassUnloading || !FLAG_IS_CMDLINE(ClassUnloadingWithConcurrentMark)) {
 177     log_info(gc)("Consider -XX:+ClassUnloadingWithConcurrentMark if large pause times "
 178                  "are observed on class-unloading sensitive workloads");
 179     FLAG_SET_DEFAULT(ClassUnloadingWithConcurrentMark, false);
 180   }
 181 
 182   // AOT is not supported yet
 183   if (UseAOT) {
 184     if (!FLAG_IS_DEFAULT(UseAOT)) {
 185       warning("Shenandoah does not support AOT at this moment, disabling UseAOT");
 186     }
 187     FLAG_SET_DEFAULT(UseAOT, false);
 188   }
 189 
 190   // TLAB sizing policy makes resizing decisions before each GC cycle. It averages
 191   // historical data, assigning more recent data the weight according to TLABAllocationWeight.
 192   // Current default is good for generational collectors that run frequent young GCs.
 193   // With Shenandoah, GC cycles are much less frequent, so we need we need sizing policy
 194   // to converge faster over smaller number of resizing decisions.
 195   if (FLAG_IS_DEFAULT(TLABAllocationWeight)) {
 196     FLAG_SET_DEFAULT(TLABAllocationWeight, 90);
 197   }
 198 




 154   }
 155 
 156   // Record more information about previous cycles for improved debugging pleasure
 157   if (FLAG_IS_DEFAULT(LogEventsBufferEntries)) {
 158     FLAG_SET_DEFAULT(LogEventsBufferEntries, 250);
 159   }
 160 
 161   if (ShenandoahAlwaysPreTouch) {
 162     if (!FLAG_IS_DEFAULT(ShenandoahUncommit)) {
 163       warning("AlwaysPreTouch is enabled, disabling ShenandoahUncommit");
 164     }
 165     FLAG_SET_DEFAULT(ShenandoahUncommit, false);
 166   }
 167 
 168   if ((InitialHeapSize == MaxHeapSize) && ShenandoahUncommit) {
 169     log_info(gc)("Min heap equals to max heap, disabling ShenandoahUncommit");
 170     FLAG_SET_DEFAULT(ShenandoahUncommit, false);
 171   }
 172 
 173   // If class unloading is disabled, no unloading for concurrent cycles as well.
 174   if (!ClassUnloading) {




 175     FLAG_SET_DEFAULT(ClassUnloadingWithConcurrentMark, false);
 176   }
 177 
 178   // AOT is not supported yet
 179   if (UseAOT) {
 180     if (!FLAG_IS_DEFAULT(UseAOT)) {
 181       warning("Shenandoah does not support AOT at this moment, disabling UseAOT");
 182     }
 183     FLAG_SET_DEFAULT(UseAOT, false);
 184   }
 185 
 186   // TLAB sizing policy makes resizing decisions before each GC cycle. It averages
 187   // historical data, assigning more recent data the weight according to TLABAllocationWeight.
 188   // Current default is good for generational collectors that run frequent young GCs.
 189   // With Shenandoah, GC cycles are much less frequent, so we need we need sizing policy
 190   // to converge faster over smaller number of resizing decisions.
 191   if (FLAG_IS_DEFAULT(TLABAllocationWeight)) {
 192     FLAG_SET_DEFAULT(TLABAllocationWeight, 90);
 193   }
 194 


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