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

Mon, 21 Jul 2014 09:41:04 +0200

author
tschatzl
date
Mon, 21 Jul 2014 09:41:04 +0200
changeset 6937
b0c374311c4e
parent 4153
b9a9ed0f8eeb
child 6876
710a3c8b516e
permissions
-rw-r--r--

8035400: Move G1ParScanThreadState into its own files
Summary: Extract the G1ParScanThreadState class from G1CollectedHeap.?pp into its own files.
Reviewed-by: brutisso, mgerdin

ysr@777 1 /*
mikael@4153 2 * Copyright (c) 2001, 2012, Oracle and/or its affiliates. All rights reserved.
ysr@777 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ysr@777 4 *
ysr@777 5 * This code is free software; you can redistribute it and/or modify it
ysr@777 6 * under the terms of the GNU General Public License version 2 only, as
ysr@777 7 * published by the Free Software Foundation.
ysr@777 8 *
ysr@777 9 * This code is distributed in the hope that it will be useful, but WITHOUT
ysr@777 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ysr@777 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
ysr@777 12 * version 2 for more details (a copy is included in the LICENSE file that
ysr@777 13 * accompanied this code).
ysr@777 14 *
ysr@777 15 * You should have received a copy of the GNU General Public License version
ysr@777 16 * 2 along with this work; if not, write to the Free Software Foundation,
ysr@777 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ysr@777 18 *
trims@1907 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907 20 * or visit www.oracle.com if you need additional information or have any
trims@1907 21 * questions.
ysr@777 22 *
ysr@777 23 */
ysr@777 24
stefank@2314 25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1MMUTRACKER_HPP
stefank@2314 26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1MMUTRACKER_HPP
stefank@2314 27
stefank@2314 28 #include "memory/allocation.hpp"
stefank@2314 29 #include "utilities/debug.hpp"
stefank@2314 30
ysr@777 31 // Keeps track of the GC work and decides when it is OK to do GC work
ysr@777 32 // and for how long so that the MMU invariants are maintained.
ysr@777 33
ysr@777 34 /***** ALL TIMES ARE IN SECS!!!!!!! *****/
ysr@777 35
ysr@777 36 // this is the "interface"
zgu@3900 37 class G1MMUTracker: public CHeapObj<mtGC> {
ysr@777 38 protected:
ysr@777 39 double _time_slice;
ysr@777 40 double _max_gc_time; // this is per time slice
ysr@777 41
ysr@777 42 public:
ysr@777 43 G1MMUTracker(double time_slice, double max_gc_time);
ysr@777 44
ysr@777 45 virtual void add_pause(double start, double end, bool gc_thread) = 0;
ysr@777 46 virtual double longest_pause(double current_time) = 0;
ysr@777 47 virtual double when_sec(double current_time, double pause_time) = 0;
ysr@777 48
ysr@777 49 double max_gc_time() {
tonyp@1371 50 return _max_gc_time;
ysr@777 51 }
ysr@777 52
ysr@777 53 inline bool now_max_gc(double current_time) {
ysr@777 54 return when_sec(current_time, max_gc_time()) < 0.00001;
ysr@777 55 }
ysr@777 56
ysr@777 57 inline double when_max_gc_sec(double current_time) {
ysr@777 58 return when_sec(current_time, max_gc_time());
ysr@777 59 }
ysr@777 60
ysr@777 61 inline jlong when_max_gc_ms(double current_time) {
ysr@777 62 double when = when_max_gc_sec(current_time);
ysr@777 63 return (jlong) (when * 1000.0);
ysr@777 64 }
ysr@777 65
ysr@777 66 inline jlong when_ms(double current_time, double pause_time) {
ysr@777 67 double when = when_sec(current_time, pause_time);
ysr@777 68 return (jlong) (when * 1000.0);
ysr@777 69 }
ysr@777 70 };
ysr@777 71
apetrusenko@984 72 class G1MMUTrackerQueueElem VALUE_OBJ_CLASS_SPEC {
ysr@777 73 private:
ysr@777 74 double _start_time;
ysr@777 75 double _end_time;
ysr@777 76
ysr@777 77 public:
ysr@777 78 inline double start_time() { return _start_time; }
ysr@777 79 inline double end_time() { return _end_time; }
ysr@777 80 inline double duration() { return _end_time - _start_time; }
ysr@777 81
ysr@777 82 G1MMUTrackerQueueElem() {
ysr@777 83 _start_time = 0.0;
ysr@777 84 _end_time = 0.0;
ysr@777 85 }
ysr@777 86
ysr@777 87 G1MMUTrackerQueueElem(double start_time, double end_time) {
ysr@777 88 _start_time = start_time;
ysr@777 89 _end_time = end_time;
ysr@777 90 }
ysr@777 91 };
ysr@777 92
ysr@777 93 // this is an implementation of the MMUTracker using a (fixed-size) queue
ysr@777 94 // that keeps track of all the recent pause times
ysr@777 95 class G1MMUTrackerQueue: public G1MMUTracker {
ysr@777 96 private:
ysr@777 97 enum PrivateConstants {
ysr@777 98 QueueLength = 64
ysr@777 99 };
ysr@777 100
ysr@777 101 // The array keeps track of all the pauses that fall within a time
ysr@777 102 // slice (the last time slice during which pauses took place).
ysr@777 103 // The data structure implemented is a circular queue.
ysr@777 104 // Head "points" to the most recent addition, tail to the oldest one.
ysr@777 105 // The array is of fixed size and I don't think we'll need more than
ysr@777 106 // two or three entries with the current behaviour of G1 pauses.
ysr@777 107 // If the array is full, an easy fix is to look for the pauses with
ysr@1523 108 // the shortest gap between them and consolidate them.
ysr@1523 109 // For now, we have taken the expedient alternative of forgetting
tonyp@1717 110 // the oldest entry in the event that +G1UseFixedWindowMMUTracker, thus
ysr@1523 111 // potentially violating MMU specs for some time thereafter.
ysr@777 112
ysr@777 113 G1MMUTrackerQueueElem _array[QueueLength];
ysr@777 114 int _head_index;
ysr@777 115 int _tail_index;
ysr@777 116 int _no_entries;
ysr@777 117
ysr@777 118 inline int trim_index(int index) {
ysr@777 119 return (index + QueueLength) % QueueLength;
ysr@777 120 }
ysr@777 121
ysr@777 122 void remove_expired_entries(double current_time);
ysr@777 123 double calculate_gc_time(double current_time);
ysr@777 124
ysr@777 125 double longest_pause_internal(double current_time);
ysr@777 126 double when_internal(double current_time, double pause_time);
ysr@777 127
ysr@777 128 public:
ysr@777 129 G1MMUTrackerQueue(double time_slice, double max_gc_time);
ysr@777 130
ysr@777 131 virtual void add_pause(double start, double end, bool gc_thread);
ysr@777 132
ysr@777 133 virtual double longest_pause(double current_time);
ysr@777 134 virtual double when_sec(double current_time, double pause_time);
ysr@777 135 };
stefank@2314 136
stefank@2314 137 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1MMUTRACKER_HPP

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