8007763: Refactoring: split up compute_generation_free_space() into two...

8007763: Refactoring: split up compute_generation_free_space() into two functions for class PSAdaptiveSizePolicy
Summary: split up compute_generation_free_space() into two functions: compute_eden_space_size() + compute_old_gen_free_space(), each of which (if needed) can be reused without executing an overhead of the other.
Reviewed-by: jmasa, tschatzl
Contributed-by: Ntamao <tao.mao@oracle.com>

src/share/vm/gc_implementation/parallelScavenge/psAdaptiveSizePolicy.hpp

 /*
- * Copyright (c) 2002, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2013, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -136,18 +136,24 @@ class PSAdaptiveSizePolicy : public AdaptiveSizePolicy {
   double gc_minor_pause_goal_sec() const { return _gc_minor_pause_goal_sec; }
 
   // Change the young generation size to achieve a minor GC pause time goal
-  void adjust_for_minor_pause_time(bool is_full_gc,
+  void adjust_promo_for_minor_pause_time(bool is_full_gc,
                                    size_t* desired_promo_size_ptr,
                                    size_t* desired_eden_size_ptr);
+  void adjust_eden_for_minor_pause_time(bool is_full_gc,
+                                   size_t* desired_eden_size_ptr);
   // Change the generation sizes to achieve a GC pause time goal
   // Returned sizes are not necessarily aligned.
-  void adjust_for_pause_time(bool is_full_gc,
+  void adjust_promo_for_pause_time(bool is_full_gc,
+                         size_t* desired_promo_size_ptr,
+                         size_t* desired_eden_size_ptr);
+  void adjust_eden_for_pause_time(bool is_full_gc,
                          size_t* desired_promo_size_ptr,
                          size_t* desired_eden_size_ptr);
   // Change the generation sizes to achieve an application throughput goal
   // Returned sizes are not necessarily aligned.
-  void adjust_for_throughput(bool is_full_gc,
-                             size_t* desired_promo_size_ptr,
+  void adjust_promo_for_throughput(bool is_full_gc,
+                             size_t* desired_promo_size_ptr);
+  void adjust_eden_for_throughput(bool is_full_gc,
                              size_t* desired_eden_size_ptr);
   // Change the generation sizes to achieve minimum footprint
   // Returned sizes are not aligned.
@@ -168,9 +174,6 @@ class PSAdaptiveSizePolicy : public AdaptiveSizePolicy {
   size_t promo_decrement_aligned_down(size_t cur_promo);
   size_t promo_increment_with_supplement_aligned_up(size_t cur_promo);
 
-  // Decay the supplemental growth additive.
-  void decay_supplemental_growth(bool is_full_gc);
-
   // Returns a change that has been scaled down.  Result
   // is not aligned.  (If useful, move to some shared
   // location.)
@@ -336,7 +339,7 @@ class PSAdaptiveSizePolicy : public AdaptiveSizePolicy {
   // perform a Full GC?
   bool should_full_GC(size_t live_in_old_gen);
 
-  // Calculates optimial free space sizes for both the old and young
+  // Calculates optimal (free) space sizes for both the young and old
   // generations.  Stores results in _eden_size and _promo_size.
   // Takes current used space in all generations as input, as well
   // as an indication if a full gc has just been performed, for use
@@ -347,9 +350,18 @@ class PSAdaptiveSizePolicy : public AdaptiveSizePolicy {
                                      size_t cur_eden,  // current eden in bytes
                                      size_t max_old_gen_size,
                                      size_t max_eden_size,
-                                     bool   is_full_gc,
-                                     GCCause::Cause gc_cause,
-                                     CollectorPolicy* collector_policy);
+                                     bool   is_full_gc);
+
+  void compute_eden_space_size(size_t young_live,
+                               size_t eden_live,
+                               size_t cur_eden,  // current eden in bytes
+                               size_t max_eden_size,
+                               bool   is_full_gc);
+
+  void compute_old_gen_free_space(size_t old_live,
+                                             size_t cur_eden,  // current eden in bytes
+                                             size_t max_old_gen_size,
+                                             bool   is_full_gc);
 
   // Calculates new survivor space size;  returns a new tenuring threshold
   // value. Stores new survivor size in _survivor_size.
@@ -390,6 +402,9 @@ class PSAdaptiveSizePolicy : public AdaptiveSizePolicy {
 
   // Printing support
   virtual bool print_adaptive_size_policy_on(outputStream* st) const;
+
+  // Decay the supplemental growth additive.
+  void decay_supplemental_growth(bool is_full_gc);
 };
 
 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSADAPTIVESIZEPOLICY_HPP

src/share/vm/gc_implementation/parallelScavenge/psMarkSweep.cpp

 /*
- * Copyright (c) 2001, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2013, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -277,19 +277,37 @@ bool PSMarkSweep::invoke_no_policy(bool clear_all_softrefs) {
           young_gen->from_space()->capacity_in_bytes() +
           young_gen->to_space()->capacity_in_bytes(),
           "Sizes of space in young gen are out-of-bounds");
+
+        size_t young_live = young_gen->used_in_bytes();
+        size_t eden_live = young_gen->eden_space()->used_in_bytes();
+        size_t old_live = old_gen->used_in_bytes();
+        size_t cur_eden = young_gen->eden_space()->capacity_in_bytes();
+        size_t max_old_gen_size = old_gen->max_gen_size();
         size_t max_eden_size = young_gen->max_size() -
           young_gen->from_space()->capacity_in_bytes() -
           young_gen->to_space()->capacity_in_bytes();
-        size_policy->compute_generation_free_space(young_gen->used_in_bytes(),
-                                 young_gen->eden_space()->used_in_bytes(),
-                                 old_gen->used_in_bytes(),
-                                 young_gen->eden_space()->capacity_in_bytes(),
-                                 old_gen->max_gen_size(),
+
+        // Used for diagnostics
+        size_policy->clear_generation_free_space_flags();
+
+        size_policy->compute_generation_free_space(young_live,
+                                                   eden_live,
+                                                   old_live,
+                                                   cur_eden,
+                                                   max_old_gen_size,
+                                                   max_eden_size,
+                                                   true /* full gc*/);
+
+        size_policy->check_gc_overhead_limit(young_live,
+                                             eden_live,
+                                             max_old_gen_size,
                                              max_eden_size,
                                              true /* full gc*/,
                                              gc_cause,
                                              heap->collector_policy());
 
+        size_policy->decay_supplemental_growth(true /* full gc*/);
+
         heap->resize_old_gen(size_policy->calculated_old_free_size_in_bytes());
 
         // Don't resize the young generation at an major collection.  A

src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp

 /*
- * Copyright (c) 2005, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -2084,20 +2084,37 @@ bool PSParallelCompact::invoke_no_policy(bool maximum_heap_compaction) {
           young_gen->from_space()->capacity_in_bytes() +
           young_gen->to_space()->capacity_in_bytes(),
           "Sizes of space in young gen are out-of-bounds");
+
+        size_t young_live = young_gen->used_in_bytes();
+        size_t eden_live = young_gen->eden_space()->used_in_bytes();
+        size_t old_live = old_gen->used_in_bytes();
+        size_t cur_eden = young_gen->eden_space()->capacity_in_bytes();
+        size_t max_old_gen_size = old_gen->max_gen_size();
         size_t max_eden_size = young_gen->max_size() -
           young_gen->from_space()->capacity_in_bytes() -
           young_gen->to_space()->capacity_in_bytes();
-        size_policy->compute_generation_free_space(
-                              young_gen->used_in_bytes(),
-                              young_gen->eden_space()->used_in_bytes(),
-                              old_gen->used_in_bytes(),
-                              young_gen->eden_space()->capacity_in_bytes(),
-                              old_gen->max_gen_size(),
+
+        // Used for diagnostics
+        size_policy->clear_generation_free_space_flags();
+
+        size_policy->compute_generation_free_space(young_live,
+                                                   eden_live,
+                                                   old_live,
+                                                   cur_eden,
+                                                   max_old_gen_size,
+                                                   max_eden_size,
+                                                   true /* full gc*/);
+
+        size_policy->check_gc_overhead_limit(young_live,
+                                             eden_live,
+                                             max_old_gen_size,
                                              max_eden_size,
                                              true /* full gc*/,
                                              gc_cause,
                                              heap->collector_policy());
 
+        size_policy->decay_supplemental_growth(true /* full gc*/);
+
         heap->resize_old_gen(
           size_policy->calculated_old_free_size_in_bytes());
 

src/share/vm/gc_implementation/parallelScavenge/psScavenge.cpp

@@ -552,19 +552,33 @@ bool PSScavenge::invoke_no_policy() {
             young_gen->from_space()->capacity_in_bytes() +
             young_gen->to_space()->capacity_in_bytes(),
             "Sizes of space in young gen are out-of-bounds");
+
+          size_t young_live = young_gen->used_in_bytes();
+          size_t eden_live = young_gen->eden_space()->used_in_bytes();
+          size_t cur_eden = young_gen->eden_space()->capacity_in_bytes();
+          size_t max_old_gen_size = old_gen->max_gen_size();
           size_t max_eden_size = young_gen->max_size() -
             young_gen->from_space()->capacity_in_bytes() -
             young_gen->to_space()->capacity_in_bytes();
-          size_policy->compute_generation_free_space(young_gen->used_in_bytes(),
-                                   young_gen->eden_space()->used_in_bytes(),
-                                   old_gen->used_in_bytes(),
-                                   young_gen->eden_space()->capacity_in_bytes(),
-                                   old_gen->max_gen_size(),
+
+          // Used for diagnostics
+          size_policy->clear_generation_free_space_flags();
+
+          size_policy->compute_eden_space_size(young_live,
+                                               eden_live,
+                                               cur_eden,
+                                               max_eden_size,
+                                               false /* not full gc*/);
+
+          size_policy->check_gc_overhead_limit(young_live,
+                                               eden_live,
+                                               max_old_gen_size,
                                                max_eden_size,
-                                   false  /* full gc*/,
+                                               false /* not full gc*/,
                                                gc_cause,
                                                heap->collector_policy());
 
+          size_policy->decay_supplemental_growth(false /* not full gc*/);
         }
         // Resize the young generation at every collection
         // even if new sizes have not been calculated.  This is