src/share/vm/memory/referencePolicy.cpp

Print this page




   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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 # include "incls/_precompiled.incl"
  26 # include "incls/_referencePolicy.cpp.incl"
  27 
  28 LRUCurrentHeapPolicy::LRUCurrentHeapPolicy() {




  29   _max_interval = (Universe::get_heap_free_at_last_gc() / M) * SoftRefLRUPolicyMSPerMB;
  30   assert(_max_interval >= 0,"Sanity check");
  31 }
  32 
  33 // The oop passed in is the SoftReference object, and not
  34 // the object the SoftReference points to.
  35 bool LRUCurrentHeapPolicy::should_clear_reference(oop p) {
  36   jlong interval = java_lang_ref_SoftReference::clock() - java_lang_ref_SoftReference::timestamp(p);
  37   assert(interval >= 0, "Sanity check");
  38 
  39   // The interval will be zero if the ref was accessed since the last scavenge/gc.
  40   if(interval <= _max_interval) {
  41     return false;
  42   }
  43 
  44   return true;
  45 }
  46 
  47 /////////////////////// MaxHeap //////////////////////
  48 
  49 LRUMaxHeapPolicy::LRUMaxHeapPolicy() {




  50   size_t max_heap = MaxHeapSize;
  51   max_heap -= Universe::get_heap_used_at_last_gc();
  52   max_heap /= M;
  53 
  54   _max_interval = max_heap * SoftRefLRUPolicyMSPerMB;
  55   assert(_max_interval >= 0,"Sanity check");
  56 }
  57 
  58 // The oop passed in is the SoftReference object, and not
  59 // the object the SoftReference points to.
  60 bool LRUMaxHeapPolicy::should_clear_reference(oop p) {
  61   jlong interval = java_lang_ref_SoftReference::clock() - java_lang_ref_SoftReference::timestamp(p);
  62   assert(interval >= 0, "Sanity check");
  63 
  64   // The interval will be zero if the ref was accessed since the last scavenge/gc.
  65   if(interval <= _max_interval) {
  66     return false;
  67   }
  68 
  69   return true;


   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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 # include "incls/_precompiled.incl"
  26 # include "incls/_referencePolicy.cpp.incl"
  27 
  28 LRUCurrentHeapPolicy::LRUCurrentHeapPolicy() {
  29   snap();
  30 }
  31 
  32 void LRUCurrentHeapPolicy::snap() {
  33   _max_interval = (Universe::get_heap_free_at_last_gc() / M) * SoftRefLRUPolicyMSPerMB;
  34   assert(_max_interval >= 0,"Sanity check");
  35 }
  36 
  37 // The oop passed in is the SoftReference object, and not
  38 // the object the SoftReference points to.
  39 bool LRUCurrentHeapPolicy::should_clear_reference(oop p) {
  40   jlong interval = java_lang_ref_SoftReference::clock() - java_lang_ref_SoftReference::timestamp(p);
  41   assert(interval >= 0, "Sanity check");
  42 
  43   // The interval will be zero if the ref was accessed since the last scavenge/gc.
  44   if(interval <= _max_interval) {
  45     return false;
  46   }
  47 
  48   return true;
  49 }
  50 
  51 /////////////////////// MaxHeap //////////////////////
  52 
  53 LRUMaxHeapPolicy::LRUMaxHeapPolicy() {
  54   snap();
  55 }
  56 
  57 void LRUMaxHeapPolicy::snap() {
  58   size_t max_heap = MaxHeapSize;
  59   max_heap -= Universe::get_heap_used_at_last_gc();
  60   max_heap /= M;
  61 
  62   _max_interval = max_heap * SoftRefLRUPolicyMSPerMB;
  63   assert(_max_interval >= 0,"Sanity check");
  64 }
  65 
  66 // The oop passed in is the SoftReference object, and not
  67 // the object the SoftReference points to.
  68 bool LRUMaxHeapPolicy::should_clear_reference(oop p) {
  69   jlong interval = java_lang_ref_SoftReference::clock() - java_lang_ref_SoftReference::timestamp(p);
  70   assert(interval >= 0, "Sanity check");
  71 
  72   // The interval will be zero if the ref was accessed since the last scavenge/gc.
  73   if(interval <= _max_interval) {
  74     return false;
  75   }
  76 
  77   return true;