Mercurial > hg > graal-compiler
annotate src/share/vm/gc_implementation/parallelScavenge/objectStartArray.cpp @ 2149:7e37af9d69ef
7011379: G1: overly long concurrent marking cycles
Summary: This changeset introduces filtering of SATB buffers at the point when they are about to be enqueued. If this filtering clears enough entries on each buffer, the buffer can then be re-used and not enqueued. This cuts down the number of SATB buffers that need to be processed by the concurrent marking threads.
Reviewed-by: johnc, ysr
author | tonyp |
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date | Wed, 19 Jan 2011 09:35:17 -0500 |
parents | f95d63e2154a |
children | d2a62e0f25eb |
rev | line source |
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0 | 1 /* |
1972 | 2 * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved. |
0 | 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 * | |
1552
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
0 | 22 * |
23 */ | |
24 | |
1972 | 25 #include "precompiled.hpp" |
26 #include "gc_implementation/parallelScavenge/objectStartArray.hpp" | |
27 #include "memory/allocation.inline.hpp" | |
28 #include "memory/cardTableModRefBS.hpp" | |
29 #include "oops/oop.inline.hpp" | |
30 #include "runtime/java.hpp" | |
0 | 31 |
32 void ObjectStartArray::initialize(MemRegion reserved_region) { | |
33 // We're based on the assumption that we use the same | |
34 // size blocks as the card table. | |
35 assert((int)block_size == (int)CardTableModRefBS::card_size, "Sanity"); | |
36 assert((int)block_size <= 512, "block_size must be less than or equal to 512"); | |
37 | |
38 // Calculate how much space must be reserved | |
39 _reserved_region = reserved_region; | |
40 | |
41 size_t bytes_to_reserve = reserved_region.word_size() / block_size_in_words; | |
42 assert(bytes_to_reserve > 0, "Sanity"); | |
43 | |
44 bytes_to_reserve = | |
45 align_size_up(bytes_to_reserve, os::vm_allocation_granularity()); | |
46 | |
47 // Do not use large-pages for the backing store. The one large page region | |
48 // will be used for the heap proper. | |
49 ReservedSpace backing_store(bytes_to_reserve); | |
50 if (!backing_store.is_reserved()) { | |
51 vm_exit_during_initialization("Could not reserve space for ObjectStartArray"); | |
52 } | |
53 | |
54 // We do not commit any memory initially | |
55 if (!_virtual_space.initialize(backing_store, 0)) { | |
56 vm_exit_during_initialization("Could not commit space for ObjectStartArray"); | |
57 } | |
58 | |
59 _raw_base = (jbyte*)_virtual_space.low_boundary(); | |
60 if (_raw_base == NULL) { | |
61 vm_exit_during_initialization("Could not get raw_base address"); | |
62 } | |
63 | |
64 _offset_base = _raw_base - (size_t(reserved_region.start()) >> block_shift); | |
65 | |
66 _covered_region.set_start(reserved_region.start()); | |
67 _covered_region.set_word_size(0); | |
68 | |
69 _blocks_region.set_start((HeapWord*)_raw_base); | |
70 _blocks_region.set_word_size(0); | |
71 } | |
72 | |
73 void ObjectStartArray::set_covered_region(MemRegion mr) { | |
74 assert(_reserved_region.contains(mr), "MemRegion outside of reserved space"); | |
75 assert(_reserved_region.start() == mr.start(), "Attempt to move covered region"); | |
76 | |
77 HeapWord* low_bound = mr.start(); | |
78 HeapWord* high_bound = mr.end(); | |
79 assert((uintptr_t(low_bound) & (block_size - 1)) == 0, "heap must start at block boundary"); | |
80 assert((uintptr_t(high_bound) & (block_size - 1)) == 0, "heap must end at block boundary"); | |
81 | |
82 size_t requested_blocks_size_in_bytes = mr.word_size() / block_size_in_words; | |
83 | |
84 // Only commit memory in page sized chunks | |
85 requested_blocks_size_in_bytes = | |
86 align_size_up(requested_blocks_size_in_bytes, os::vm_page_size()); | |
87 | |
88 _covered_region = mr; | |
89 | |
90 size_t current_blocks_size_in_bytes = _blocks_region.byte_size(); | |
91 | |
92 if (requested_blocks_size_in_bytes > current_blocks_size_in_bytes) { | |
93 // Expand | |
94 size_t expand_by = requested_blocks_size_in_bytes - current_blocks_size_in_bytes; | |
95 if (!_virtual_space.expand_by(expand_by)) { | |
96 vm_exit_out_of_memory(expand_by, "object start array expansion"); | |
97 } | |
98 // Clear *only* the newly allocated region | |
99 memset(_blocks_region.end(), clean_block, expand_by); | |
100 } | |
101 | |
102 if (requested_blocks_size_in_bytes < current_blocks_size_in_bytes) { | |
103 // Shrink | |
104 size_t shrink_by = current_blocks_size_in_bytes - requested_blocks_size_in_bytes; | |
105 _virtual_space.shrink_by(shrink_by); | |
106 } | |
107 | |
108 _blocks_region.set_word_size(requested_blocks_size_in_bytes / sizeof(HeapWord)); | |
109 | |
110 assert(requested_blocks_size_in_bytes % sizeof(HeapWord) == 0, "Block table not expanded in word sized increment"); | |
111 assert(requested_blocks_size_in_bytes == _blocks_region.byte_size(), "Sanity"); | |
112 assert(block_for_addr(low_bound) == &_raw_base[0], "Checking start of map"); | |
113 assert(block_for_addr(high_bound-1) <= &_raw_base[_blocks_region.byte_size()-1], "Checking end of map"); | |
114 } | |
115 | |
116 void ObjectStartArray::reset() { | |
117 memset(_blocks_region.start(), clean_block, _blocks_region.byte_size()); | |
118 } | |
119 | |
120 | |
121 bool ObjectStartArray::object_starts_in_range(HeapWord* start_addr, | |
122 HeapWord* end_addr) const { | |
123 assert(start_addr <= end_addr, "range is wrong"); | |
124 if (start_addr > end_addr) { | |
125 return false; | |
126 } | |
127 | |
128 jbyte* start_block = block_for_addr(start_addr); | |
129 jbyte* end_block = block_for_addr(end_addr); | |
130 | |
131 for (jbyte* block = start_block; block <= end_block; block++) { | |
132 if (*block != clean_block) { | |
133 return true; | |
134 } | |
135 } | |
136 // No object starts in this slice; verify this using | |
137 // more traditional methods: | |
138 assert(object_start(end_addr - 1) <= start_addr, | |
139 "Oops an object does start in this slice?"); | |
140 return false; | |
141 } |