view src/share/vm/gc_implementation/shared/generationCounters.hpp @ 3766:c3f1170908be

7045330: G1: Simplify/fix the HeapRegionSeq class 7042285: G1: native memory leak during humongous object allocation 6804436: G1: heap region indices should be size_t Summary: A series of fixes and improvements to the HeapRegionSeq class: a) replace the _regions growable array with a standard C array, b) avoid de-allocating / re-allocating HeapRegion instances when the heap shrinks / grows (fix for 7042285), c) introduce fast method to map address to HeapRegion via a "biased" array pointer, d) embed the _hrs object in G1CollectedHeap, instead of pointing to it via an indirection, e) assume that all the regions added to the HeapRegionSeq instance are contiguous, f) replace int's with size_t's for indexes (and expand that to HeapRegion as part of 6804436), g) remove unnecessary / unused methods, h) rename a couple of fields (_alloc_search_start and _seq_bottom), i) fix iterate_from() not to always start from index 0 irrespective of the region passed to it, j) add a verification method to check the HeapRegionSeq assumptions, k) always call the wrappers for _hrs.iterate(), _hrs_length(), and _hrs.at() from G1CollectedHeap, not those methods directly, and l) unify the code that expands the sequence (by either re-using or creating a new HeapRegion) and make it robust wrt to a HeapRegion allocation failing. Reviewed-by: stefank, johnc, brutisso
author tonyp
date Fri, 10 Jun 2011 13:16:40 -0400
parents b52782ae3880
children 8229bd737950
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/*
 * Copyright (c) 2002, 2011, 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
 * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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#ifndef SHARE_VM_GC_IMPLEMENTATION_SHARED_GENERATIONCOUNTERS_HPP
#define SHARE_VM_GC_IMPLEMENTATION_SHARED_GENERATIONCOUNTERS_HPP

#include "runtime/perfData.hpp"
#include "runtime/virtualspace.hpp"

// A GenerationCounter is a holder class for performance counters
// that track a generation

class GenerationCounters: public CHeapObj {
  friend class VMStructs;

 protected:
  PerfVariable*      _current_size;
  VirtualSpace*      _virtual_space;

  // Constant PerfData types don't need to retain a reference.
  // However, it's a good idea to document them here.
  // PerfStringConstant*     _name;
  // PerfConstant*           _min_size;
  // PerfConstant*           _max_size;
  // PerfConstant*           _spaces;

  char*              _name_space;

  // This constructor is only meant for use with the PSGenerationCounters
  // constructor.  The need for such an constructor should be eliminated
  // when VirtualSpace and PSVirtualSpace are unified.
  GenerationCounters() : _name_space(NULL), _current_size(NULL), _virtual_space(NULL) {}
 public:

  GenerationCounters(const char* name, int ordinal, int spaces,
                     VirtualSpace* v);

  ~GenerationCounters() {
    if (_name_space != NULL) FREE_C_HEAP_ARRAY(char, _name_space);
  }

  virtual void update_all() {
    _current_size->set_value(_virtual_space == NULL ? 0 :
                             _virtual_space->committed_size());
  }

  const char* name_space() const        { return _name_space; }

};
#endif // SHARE_VM_GC_IMPLEMENTATION_SHARED_GENERATIONCOUNTERS_HPP