view src/share/vm/memory/classify.cpp @ 1994:6cd6d394f280

7001033: assert(gch->gc_cause() == GCCause::_scavenge_alot || !gch->incremental_collection_failed()) 7002546: regression on SpecJbb2005 on 7b118 comparing to 7b117 on small heaps Summary: Relaxed assertion checking related to incremental_collection_failed flag to allow for ExplicitGCInvokesConcurrent behaviour where we do not want a failing scavenge to bail to a stop-world collection. Parameterized incremental_collection_will_fail() so we can selectively use, or not use, as appropriate, the statistical prediction at specific use sites. This essentially reverts the scavenge bail-out logic to what it was prior to some recent changes that had inadvertently started using the statistical prediction which can be noisy in the presence of bursty loads. Added some associated verbose non-product debugging messages. Reviewed-by: johnc, tonyp
author ysr
date Tue, 07 Dec 2010 21:55:53 -0800
parents f95d63e2154a
children 3582bf76420e
line wrap: on
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/*
 * Copyright (c) 2003, 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 "memory/classify.hpp"


const char* ClassifyObjectClosure::object_type_name[number_object_types] = {
  "unknown",
  "instance",
  "instanceRef",
  "objArray",
  "symbol",
  "klass",
  "instanceKlass",
  "method",
  "constMethod",
  "methodData",
  "constantPool",
  "constantPoolCache",
  "typeArray",
  "compiledICHolder"
};


object_type ClassifyObjectClosure::classify_object(oop obj, bool count) {
  object_type type = unknown_type;

  Klass* k = obj->blueprint();

  if (k->as_klassOop() == SystemDictionary::Object_klass()) {
    tty->print_cr("Found the class!");
  }

  if (count) {
    k->set_alloc_count(k->alloc_count() + 1);
  }

  if (obj->is_instance()) {
    if (k->oop_is_instanceRef()) {
      type = instanceRef_type;
    } else {
      type = instance_type;
    }
  } else if (obj->is_typeArray()) {
    type = typeArray_type;
  } else if (obj->is_objArray()) {
    type = objArray_type;
  } else if (obj->is_symbol()) {
    type = symbol_type;
  } else if (obj->is_klass()) {
    Klass* k = ((klassOop)obj)->klass_part();
    if (k->oop_is_instance()) {
      type = instanceKlass_type;
    } else {
      type = klass_type;
    }
  } else if (obj->is_method()) {
    type = method_type;
  } else if (obj->is_constMethod()) {
    type = constMethod_type;
  } else if (obj->is_methodData()) {
    ShouldNotReachHere();
  } else if (obj->is_constantPool()) {
    type = constantPool_type;
  } else if (obj->is_constantPoolCache()) {
    type = constantPoolCache_type;
  } else if (obj->is_compiledICHolder()) {
    type = compiledICHolder_type;
  } else {
    ShouldNotReachHere();
  }

  assert(type != unknown_type, "found object of unknown type.");
  return type;
}


void ClassifyObjectClosure::reset() {
  for (int i = 0; i < number_object_types; ++i) {
    object_count[i] = 0;
    object_size[i] = 0;
  }
  total_object_count = 0;
  total_object_size = 0;
}


void ClassifyObjectClosure::do_object(oop obj) {
  int i = classify_object(obj, true);
  ++object_count[i];
  ++total_object_count;
  size_t size = obj->size() * HeapWordSize;
  object_size[i] += size;
  total_object_size += size;
}


size_t ClassifyObjectClosure::print() {
  int num_objects = 0;
  size_t size_objects = 0;
  for (int i = 0; i < number_object_types; ++i) {
    if (object_count[i] != 0) {
      tty->print_cr("%8d  %-22s  (%8d bytes, %5.2f bytes/object)",
                    object_count[i], object_type_name[i], object_size[i],
                    (float)object_size[i]/(float)object_count[i]);
    }
    num_objects += object_count[i];
    size_objects += object_size[i];
  }
  assert(num_objects == total_object_count, "Object count mismatch!");
  assert(size_objects == total_object_size, "Object size mismatch!");

  tty->print_cr(" Total:  %d objects, %d bytes", total_object_count,
                total_object_size);
  return total_object_size;
}


void ClassifyInstanceKlassClosure::do_object(oop obj) {
  int type = classify_object(obj, false);
  if (type == instanceKlass_type || type == klass_type) {
    Klass* k = ((klassOop)obj)->klass_part();
    if (k->alloc_count() > 0) {
      ResourceMark rm;
      const char *name;
      if (k->name() == NULL) {

        if (obj == Universe::klassKlassObj()) {
          name = "_klassKlassObj";
        } else if (obj == Universe::arrayKlassKlassObj()) {
          name = "_arrayKlassKlassObj";
        } else if (obj == Universe::objArrayKlassKlassObj()) {
          name = "_objArrayKlassKlassObj";
        } else if (obj == Universe::typeArrayKlassKlassObj()) {
          name = "_typeArrayKlassKlassObj";
        } else if (obj == Universe::instanceKlassKlassObj()) {
          name = "_instanceKlassKlassObj";
        } else if (obj == Universe::symbolKlassObj()) {
          name = "_symbolKlassObj";
        } else if (obj == Universe::methodKlassObj()) {
          name = "_methodKlassObj";
        } else if (obj == Universe::constMethodKlassObj()) {
          name = "_constMethodKlassObj";
        } else if (obj == Universe::constantPoolKlassObj()) {
          name = "_constantPoolKlassObj";
        } else if (obj == Universe::constantPoolCacheKlassObj()) {
          name = "_constantPoolCacheKlassObj";
        } else if (obj == Universe::compiledICHolderKlassObj()) {
          name = "_compiledICHolderKlassObj";
        } else if (obj == Universe::systemObjArrayKlassObj()) {
          name = "_systemObjArrayKlassObj";
        } else {
          name = "[unnamed]";
        }
      } else {
        name = k->external_name();
      }
      tty->print_cr("% 8d  instances of %s", k->alloc_count(), name);
    }
    total_instances += k->alloc_count();
  }
}


void ClassifyInstanceKlassClosure::print() {
  tty->print_cr(" Total instances:  %d.", total_instances);
}


void ClassifyInstanceKlassClosure::reset() {
  total_instances = 0;
}