view src/share/vm/runtime/aprofiler.cpp @ 3917:eca1193ca245

4965777: GC changes to support use of discovered field for pending references Summary: If and when the reference handler thread is able to use the discovered field to link reference objects in its pending list, so will GC. In that case, GC will scan through this field once a reference object has been placed on the pending list, but not scan that field before that stage, as the field is used by the concurrent GC thread to link discovered objects. When ReferenceHandleR thread does not use the discovered field for the purpose of linking the elements in the pending list, as would be the case in older JDKs, the JVM will fall back to the old behaviour of using the next field for that purpose. Reviewed-by: jcoomes, mchung, stefank
author ysr
date Wed, 07 Sep 2011 13:55:42 -0700
parents f95d63e2154a
children da91efe96a93
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/*
 * Copyright (c) 1997, 2010, 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#include "precompiled.hpp"
#include "classfile/systemDictionary.hpp"
#include "gc_interface/collectedHeap.inline.hpp"
#include "memory/permGen.hpp"
#include "memory/resourceArea.hpp"
#include "memory/space.hpp"
#include "oops/oop.inline.hpp"
#include "oops/oop.inline2.hpp"
#include "runtime/aprofiler.hpp"


bool AllocationProfiler::_active = false;
GrowableArray<klassOop>* AllocationProfiler::_print_array = NULL;


class AllocProfClosure : public ObjectClosure {
 public:
  void do_object(oop obj) {
    Klass* k = obj->blueprint();
    k->set_alloc_count(k->alloc_count() + 1);
    k->set_alloc_size(k->alloc_size() + obj->size());
  }
};


#ifndef PRODUCT

class AllocProfResetClosure : public ObjectClosure {
 public:
  void do_object(oop obj) {
    if (obj->is_klass()) {
      Klass* k = Klass::cast(klassOop(obj));
      k->set_alloc_count(0);
      k->set_alloc_size(0);
    }
  }
};

#endif


void AllocationProfiler::iterate_since_last_gc() {
  if (is_active()) {
    AllocProfClosure blk;
    GenCollectedHeap* heap = GenCollectedHeap::heap();
    heap->object_iterate_since_last_GC(&blk);
  }
}


void AllocationProfiler::engage() {
  _active = true;
}


void AllocationProfiler::disengage() {
  _active = false;
}


void AllocationProfiler::add_class_to_array(klassOop k) {
  _print_array->append(k);
}


void AllocationProfiler::add_classes_to_array(klassOop k) {
  // Iterate over klass and all array klasses for klass
  k->klass_part()->with_array_klasses_do(&AllocationProfiler::add_class_to_array);
}


int AllocationProfiler::compare_classes(klassOop* k1, klassOop* k2) {
  // Sort by total allocation size
  return (*k2)->klass_part()->alloc_size() - (*k1)->klass_part()->alloc_size();
}


int AllocationProfiler::average(size_t alloc_size, int alloc_count) {
  return (int) ((double) (alloc_size * BytesPerWord) / MAX2(alloc_count, 1) + 0.5);
}


void AllocationProfiler::sort_and_print_array(size_t cutoff) {
  _print_array->sort(&AllocationProfiler::compare_classes);
  tty->print_cr("________________Size"
                "__Instances"
                "__Average"
                "__Class________________");
  size_t total_alloc_size = 0;
  int total_alloc_count = 0;
  for (int index = 0; index < _print_array->length(); index++) {
    klassOop k = _print_array->at(index);
    size_t alloc_size = k->klass_part()->alloc_size();
    if (alloc_size > cutoff) {
      int alloc_count = k->klass_part()->alloc_count();
#ifdef PRODUCT
      const char* name = k->klass_part()->external_name();
#else
      const char* name = k->klass_part()->internal_name();
#endif
      tty->print_cr("%20u %10u %8u  %s",
        alloc_size * BytesPerWord,
        alloc_count,
        average(alloc_size, alloc_count),
        name);
      total_alloc_size += alloc_size;
      total_alloc_count += alloc_count;
    }
  }
  tty->print_cr("%20u %10u %8u  --total--",
    total_alloc_size * BytesPerWord,
    total_alloc_count,
    average(total_alloc_size, total_alloc_count));
  tty->cr();
}


void AllocationProfiler::print(size_t cutoff) {
  ResourceMark rm;
  assert(!is_active(), "AllocationProfiler cannot be active while printing profile");

  tty->cr();
  tty->print_cr("Allocation profile (sizes in bytes, cutoff = %ld bytes):", cutoff * BytesPerWord);
  tty->cr();

  // Print regular instance klasses and basic type array klasses
  _print_array = new GrowableArray<klassOop>(SystemDictionary::number_of_classes()*2);
  SystemDictionary::classes_do(&add_classes_to_array);
  Universe::basic_type_classes_do(&add_classes_to_array);
  sort_and_print_array(cutoff);

  #ifndef PRODUCT
  tty->print_cr("Allocation profile for system classes (sizes in bytes, cutoff = %d bytes):", cutoff * BytesPerWord);
  tty->cr();

  // Print system klasses (methods, symbols, constant pools, etc.)
  _print_array = new GrowableArray<klassOop>(64);
  Universe::system_classes_do(&add_classes_to_array);
  sort_and_print_array(cutoff);

  tty->print_cr("Permanent generation dump (sizes in bytes, cutoff = %d bytes):", cutoff * BytesPerWord);
  tty->cr();

  AllocProfResetClosure resetblk;
  Universe::heap()->permanent_object_iterate(&resetblk);
  AllocProfClosure blk;
  Universe::heap()->permanent_object_iterate(&blk);

  _print_array = new GrowableArray<klassOop>(SystemDictionary::number_of_classes()*2);
  SystemDictionary::classes_do(&add_classes_to_array);
  Universe::basic_type_classes_do(&add_classes_to_array);
  Universe::system_classes_do(&add_classes_to_array);
  sort_and_print_array(cutoff);
  #endif
}