Mercurial > hg > truffle

diff src/share/vm/gc_implementation/g1/vm_operations_g1.hpp @ 1973:631f79e71e90

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
6974966: G1: unnecessary direct-to-old allocations Summary: This change revamps the slow allocation path of G1. Improvements include the following: a) Allocations directly to old regions are now totally banned. G1 now only allows allocations out of young regions (with the only exception being humongous regions). b) The thread that allocates a new region (which is now guaranteed to be young) does not dirty all its cards. Each thread that successfully allocates out of a young region is now responsible for dirtying the cards that corresponding to the "block" that just got allocated. c) allocate_new_tlab() and mem_allocate() are now implemented differently and TLAB allocations are only done by allocate_new_tlab(). d) If a thread schedules an evacuation pause in order to satisfy an allocation request, it will perform the allocation at the end of the safepoint so that the thread that initiated the GC also gets "first pick" of any space made available by the GC. e) If a thread is unable to allocate a humongous object it will schedule an evacuation pause in case it reclaims enough regions so that the humongous allocation can be satisfied aftewards. f) The G1 policy is more careful to set the young list target length to be the survivor number +1. g) Lots of code tidy up, removal, refactoring to make future changes easier. Reviewed-by: johnc, ysr
author tonyp
date Tue, 24 Aug 2010 17:24:33 -0400
parents f95d63e2154a
children c798c277ddd1
line wrap: on
line diff
--- a/src/share/vm/gc_implementation/g1/vm_operations_g1.hpp	Tue Nov 23 13:22:55 2010 -0800
+++ b/src/share/vm/gc_implementation/g1/vm_operations_g1.hpp	Tue Aug 24 17:24:33 2010 -0400
@@ -31,19 +31,33 @@
 // VM_GC_Operation:
 //   - VM_CGC_Operation
 //   - VM_G1CollectFull
-//   - VM_G1CollectForAllocation
-//   - VM_G1IncCollectionPause
-//   - VM_G1PopRegionCollectionPause
+//   - VM_G1OperationWithAllocRequest
+//     - VM_G1CollectForAllocation
+//     - VM_G1IncCollectionPause
+
+class VM_G1OperationWithAllocRequest: public VM_GC_Operation {
+protected:
+  size_t    _word_size;
+  HeapWord* _result;
+  bool      _pause_succeeded;
+
+public:
+  VM_G1OperationWithAllocRequest(unsigned int gc_count_before,
+                                 size_t       word_size)
+    : VM_GC_Operation(gc_count_before),
+      _word_size(word_size), _result(NULL), _pause_succeeded(false) { }
+  HeapWord* result() { return _result; }
+  bool pause_succeeded() { return _pause_succeeded; }
+};
 
 class VM_G1CollectFull: public VM_GC_Operation {
- public:
+public:
   VM_G1CollectFull(unsigned int gc_count_before,
                    unsigned int full_gc_count_before,
                    GCCause::Cause cause)
     : VM_GC_Operation(gc_count_before, full_gc_count_before) {
     _gc_cause = cause;
   }
-  ~VM_G1CollectFull() {}
   virtual VMOp_Type type() const { return VMOp_G1CollectFull; }
   virtual void doit();
   virtual const char* name() const {
@@ -51,45 +65,28 @@
   }
 };
 
-class VM_G1CollectForAllocation: public VM_GC_Operation {
- private:
-  HeapWord*   _res;
-  size_t      _size;                       // size of object to be allocated
- public:
-  VM_G1CollectForAllocation(size_t size, int gc_count_before)
-    : VM_GC_Operation(gc_count_before) {
-    _size        = size;
-    _res         = NULL;
-  }
-  ~VM_G1CollectForAllocation()        {}
+class VM_G1CollectForAllocation: public VM_G1OperationWithAllocRequest {
+public:
+  VM_G1CollectForAllocation(unsigned int gc_count_before,
+                            size_t       word_size);
   virtual VMOp_Type type() const { return VMOp_G1CollectForAllocation; }
   virtual void doit();
   virtual const char* name() const {
     return "garbage-first collection to satisfy allocation";
   }
-  HeapWord* result() { return _res; }
 };
 
-class VM_G1IncCollectionPause: public VM_GC_Operation {
+class VM_G1IncCollectionPause: public VM_G1OperationWithAllocRequest {
 private:
-  bool _should_initiate_conc_mark;
-  double _target_pause_time_ms;
+  bool         _should_initiate_conc_mark;
+  double       _target_pause_time_ms;
   unsigned int _full_collections_completed_before;
 public:
   VM_G1IncCollectionPause(unsigned int   gc_count_before,
+                          size_t         word_size,
                           bool           should_initiate_conc_mark,
                           double         target_pause_time_ms,
-                          GCCause::Cause cause)
-    : VM_GC_Operation(gc_count_before),
-      _full_collections_completed_before(0),
-      _should_initiate_conc_mark(should_initiate_conc_mark),
-      _target_pause_time_ms(target_pause_time_ms) {
-    guarantee(target_pause_time_ms > 0.0,
-              err_msg("target_pause_time_ms = %1.6lf should be positive",
-                      target_pause_time_ms));
-
-    _gc_cause = cause;
-  }
+                          GCCause::Cause gc_cause);
   virtual VMOp_Type type() const { return VMOp_G1IncCollectionPause; }
   virtual void doit();
   virtual void doit_epilogue();
@@ -103,14 +100,9 @@
 class VM_CGC_Operation: public VM_Operation {
   VoidClosure* _cl;
   const char* _printGCMessage;
- public:
-  VM_CGC_Operation(VoidClosure* cl, const char *printGCMsg) :
-    _cl(cl),
-    _printGCMessage(printGCMsg)
-    {}
-
-  ~VM_CGC_Operation() {}
-
+public:
+  VM_CGC_Operation(VoidClosure* cl, const char *printGCMsg)
+    : _cl(cl), _printGCMessage(printGCMsg) { }
   virtual VMOp_Type type() const { return VMOp_CGC_Operation; }
   virtual void doit();
   virtual bool doit_prologue();