view src/share/vm/gc_implementation/parallelScavenge/psMarkSweep.hpp @ 453:c96030fff130

6684579: SoftReference processing can be made more efficient Summary: For current soft-ref clearing policies, we can decide at marking time if a soft-reference will definitely not be cleared, postponing the decision of whether it will definitely be cleared to the final reference processing phase. This can be especially beneficial in the case of concurrent collectors where the marking is usually concurrent but reference processing is usually not. Reviewed-by: jmasa
author ysr
date Thu, 20 Nov 2008 16:56:09 -0800
parents a61af66fc99e
children c18cbe5936b8
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/*
 * Copyright 2001-2005 Sun Microsystems, Inc.  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
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

class PSAdaptiveSizePolicy;
class PSYoungGen;
class PSOldGen;

class PSMarkSweep : public MarkSweep {
 private:
  static elapsedTimer        _accumulated_time;
  static unsigned int        _total_invocations;
  static jlong               _time_of_last_gc;   // ms
  static CollectorCounters*  _counters;

  // Closure accessors
  static OopClosure* mark_and_push_closure() { return &MarkSweep::mark_and_push_closure; }
  static VoidClosure* follow_stack_closure() { return (VoidClosure*)&MarkSweep::follow_stack_closure; }
  static OopClosure* adjust_pointer_closure() { return (OopClosure*)&MarkSweep::adjust_pointer_closure; }
  static OopClosure* adjust_root_pointer_closure() { return (OopClosure*)&MarkSweep::adjust_root_pointer_closure; }
  static BoolObjectClosure* is_alive_closure() { return (BoolObjectClosure*)&MarkSweep::is_alive; }

 debug_only(public:)  // Used for PSParallelCompact debugging
  // Mark live objects
  static void mark_sweep_phase1(bool clear_all_softrefs);
  // Calculate new addresses
  static void mark_sweep_phase2();
 debug_only(private:) // End used for PSParallelCompact debugging
  // Update pointers
  static void mark_sweep_phase3();
  // Move objects to new positions
  static void mark_sweep_phase4();

 debug_only(public:)  // Used for PSParallelCompact debugging
  // Temporary data structures for traversal and storing/restoring marks
  static void allocate_stacks();
  static void deallocate_stacks();
  static void set_ref_processor(ReferenceProcessor* rp) {  // delete this method
    _ref_processor = rp;
  }
 debug_only(private:) // End used for PSParallelCompact debugging

  // If objects are left in eden after a collection, try to move the boundary
  // and absorb them into the old gen.  Returns true if eden was emptied.
  static bool absorb_live_data_from_eden(PSAdaptiveSizePolicy* size_policy,
                                         PSYoungGen* young_gen,
                                         PSOldGen* old_gen);

  // Reset time since last full gc
  static void reset_millis_since_last_gc();

 public:
  static void invoke(bool clear_all_softrefs);
  static void invoke_no_policy(bool clear_all_softrefs);

  static void initialize();

  // Public accessors
  static elapsedTimer* accumulated_time() { return &_accumulated_time; }
  static unsigned int total_invocations() { return _total_invocations; }
  static CollectorCounters* counters()    { return _counters; }

  // Time since last full gc (in milliseconds)
  static jlong millis_since_last_gc();
};