jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/g1MMUTracker.hpp@fa08949fe0cb

8009536: G1: Apache Lucene hang during reference processing
Summary: In CMTask::do_marking_step(), Skip offering termination and entering the first and second synchronization barriers if called from a serial context, i.e. the VM thread.
Reviewed-by: brutisso, tschatzl

     1 /*

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     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

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    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

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    23  */

    25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1MMUTRACKER_HPP

    26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1MMUTRACKER_HPP

    28 #include "memory/allocation.hpp"

    29 #include "utilities/debug.hpp"

    31 // Keeps track of the GC work and decides when it is OK to do GC work

    32 // and for how long so that the MMU invariants are maintained.

    34 /***** ALL TIMES ARE IN SECS!!!!!!! *****/

    36 // this is the "interface"

    37 class G1MMUTracker: public CHeapObj<mtGC> {

    38 protected:

    39   double          _time_slice;

    40   double          _max_gc_time; // this is per time slice

    42 public:

    43   G1MMUTracker(double time_slice, double max_gc_time);

    45   virtual void add_pause(double start, double end, bool gc_thread) = 0;

    46   virtual double longest_pause(double current_time) = 0;

    47   virtual double when_sec(double current_time, double pause_time) = 0;

    49   double max_gc_time() {

    50     return _max_gc_time;

    51   }

    53   inline bool now_max_gc(double current_time) {

    54     return when_sec(current_time, max_gc_time()) < 0.00001;

    55   }

    57   inline double when_max_gc_sec(double current_time) {

    58     return when_sec(current_time, max_gc_time());

    59   }

    61   inline jlong when_max_gc_ms(double current_time) {

    62     double when = when_max_gc_sec(current_time);

    63     return (jlong) (when * 1000.0);

    64   }

    66   inline jlong when_ms(double current_time, double pause_time) {

    67     double when = when_sec(current_time, pause_time);

    68     return (jlong) (when * 1000.0);

    69   }

    70 };

    72 class G1MMUTrackerQueueElem VALUE_OBJ_CLASS_SPEC {

    73 private:

    74   double _start_time;

    75   double _end_time;

    77 public:

    78   inline double start_time() { return _start_time; }

    79   inline double end_time()   { return _end_time; }

    80   inline double duration()   { return _end_time - _start_time; }

    82   G1MMUTrackerQueueElem() {

    83     _start_time = 0.0;

    84     _end_time   = 0.0;

    85   }

    87   G1MMUTrackerQueueElem(double start_time, double end_time) {

    88     _start_time = start_time;

    89     _end_time   = end_time;

    90   }

    91 };

    93 // this is an implementation of the MMUTracker using a (fixed-size) queue

    94 // that keeps track of all the recent pause times

    95 class G1MMUTrackerQueue: public G1MMUTracker {

    96 private:

    97   enum PrivateConstants {

    98     QueueLength = 64

    99   };

   101   // The array keeps track of all the pauses that fall within a time

   102   // slice (the last time slice during which pauses took place).

   103   // The data structure implemented is a circular queue.

   104   // Head "points" to the most recent addition, tail to the oldest one.

   105   // The array is of fixed size and I don't think we'll need more than

   106   // two or three entries with the current behaviour of G1 pauses.

   107   // If the array is full, an easy fix is to look for the pauses with

   108   // the shortest gap between them and consolidate them.

   109   // For now, we have taken the expedient alternative of forgetting

   110   // the oldest entry in the event that +G1UseFixedWindowMMUTracker, thus

   111   // potentially violating MMU specs for some time thereafter.

   113   G1MMUTrackerQueueElem _array[QueueLength];

   114   int                   _head_index;

   115   int                   _tail_index;

   116   int                   _no_entries;

   118   inline int trim_index(int index) {

   119     return (index + QueueLength) % QueueLength;

   120   }

   122   void remove_expired_entries(double current_time);

   123   double calculate_gc_time(double current_time);

   125   double longest_pause_internal(double current_time);

   126   double when_internal(double current_time, double pause_time);

   128 public:

   129   G1MMUTrackerQueue(double time_slice, double max_gc_time);

   131   virtual void add_pause(double start, double end, bool gc_thread);

   133   virtual double longest_pause(double current_time);

   134   virtual double when_sec(double current_time, double pause_time);

   135 };

   137 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1MMUTRACKER_HPP

Mercurial > jdk8-mips64-public > hotspot / file revision

src/share/vm/gc_implementation/g1/g1MMUTracker.hpp@fa08949fe0cb

src/share/vm/gc_implementation/g1/g1MMUTracker.hpp