1 /*
   2  * Copyright (c) 2000, 2008, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 # include "incls/_precompiled.incl"
  26 # include "incls/_referencePolicy.cpp.incl"




  27 
  28 LRUCurrentHeapPolicy::LRUCurrentHeapPolicy() {
  29   setup();
  30 }
  31 
  32 // Capture state (of-the-VM) information needed to evaluate the policy
  33 void LRUCurrentHeapPolicy::setup() {
  34   _max_interval = (Universe::get_heap_free_at_last_gc() / M) * SoftRefLRUPolicyMSPerMB;
  35   assert(_max_interval >= 0,"Sanity check");
  36 }
  37 
  38 // The oop passed in is the SoftReference object, and not
  39 // the object the SoftReference points to.
  40 bool LRUCurrentHeapPolicy::should_clear_reference(oop p) {
  41   jlong interval = java_lang_ref_SoftReference::clock() - java_lang_ref_SoftReference::timestamp(p);
  42   assert(interval >= 0, "Sanity check");
  43 
  44   // The interval will be zero if the ref was accessed since the last scavenge/gc.
  45   if(interval <= _max_interval) {
  46     return false;

   1 /*
   2  * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/javaClasses.hpp"
  27 #include "memory/referencePolicy.hpp"
  28 #include "memory/universe.hpp"
  29 #include "runtime/arguments.hpp"
  30 #include "runtime/globals.hpp"
  31 
  32 LRUCurrentHeapPolicy::LRUCurrentHeapPolicy() {
  33   setup();
  34 }
  35 
  36 // Capture state (of-the-VM) information needed to evaluate the policy
  37 void LRUCurrentHeapPolicy::setup() {
  38   _max_interval = (Universe::get_heap_free_at_last_gc() / M) * SoftRefLRUPolicyMSPerMB;
  39   assert(_max_interval >= 0,"Sanity check");
  40 }
  41 
  42 // The oop passed in is the SoftReference object, and not
  43 // the object the SoftReference points to.
  44 bool LRUCurrentHeapPolicy::should_clear_reference(oop p) {
  45   jlong interval = java_lang_ref_SoftReference::clock() - java_lang_ref_SoftReference::timestamp(p);
  46   assert(interval >= 0, "Sanity check");
  47 
  48   // The interval will be zero if the ref was accessed since the last scavenge/gc.
  49   if(interval <= _max_interval) {
  50     return false;