Mon, 12 Mar 2012 14:59:00 -0700
7147724: G1: hang in SurrogateLockerThread::manipulatePLL
Summary: Attempting to initiate a marking cycle when allocating a humongous object can, if a marking cycle is successfully initiated by another thread, result in the allocating thread spinning until the marking cycle is complete. Eliminate a deadlock between the main ConcurrentMarkThread, the SurrogateLocker thread, the VM thread, and a mutator thread waiting on the SecondaryFreeList_lock (while free regions are going to become available) by not manipulating the pending list lock during the prologue and epilogue of the cleanup pause.
Reviewed-by: brutisso, jcoomes, tonyp
1 /*
2 * Copyright (c) 2001, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
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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.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 */
25 #include "precompiled.hpp"
26 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
27 #include "gc_implementation/g1/g1CollectorPolicy.hpp"
28 #include "gc_implementation/g1/heapRegion.hpp"
29 #include "gc_implementation/g1/survRateGroup.hpp"
30 #include "memory/allocation.hpp"
32 SurvRateGroup::SurvRateGroup(G1CollectorPolicy* g1p,
33 const char* name,
34 size_t summary_surv_rates_len) :
35 _g1p(g1p), _name(name),
36 _summary_surv_rates_len(summary_surv_rates_len),
37 _summary_surv_rates_max_len(0),
38 _summary_surv_rates(NULL),
39 _surv_rate(NULL),
40 _accum_surv_rate_pred(NULL),
41 _surv_rate_pred(NULL),
42 _stats_arrays_length(0) {
43 reset();
44 if (summary_surv_rates_len > 0) {
45 size_t length = summary_surv_rates_len;
46 _summary_surv_rates = NEW_C_HEAP_ARRAY(NumberSeq*, length);
47 for (size_t i = 0; i < length; ++i) {
48 _summary_surv_rates[i] = new NumberSeq();
49 }
50 }
52 start_adding_regions();
53 }
55 void SurvRateGroup::reset() {
56 _all_regions_allocated = 0;
57 _setup_seq_num = 0;
58 _accum_surv_rate = 0.0;
59 _last_pred = 0.0;
60 // the following will set up the arrays with length 1
61 _region_num = 1;
63 // The call to stop_adding_regions() will use "new" to refill
64 // the _surv_rate_pred array, so we need to make sure to call
65 // "delete".
66 for (size_t i = 0; i < _stats_arrays_length; ++i) {
67 delete _surv_rate_pred[i];
68 }
69 _stats_arrays_length = 0;
71 stop_adding_regions();
72 guarantee( _stats_arrays_length == 1, "invariant" );
73 guarantee( _surv_rate_pred[0] != NULL, "invariant" );
74 _surv_rate_pred[0]->add(0.4);
75 all_surviving_words_recorded(false);
76 _region_num = 0;
77 }
79 void
80 SurvRateGroup::start_adding_regions() {
81 _setup_seq_num = _stats_arrays_length;
82 _region_num = 0;
83 _accum_surv_rate = 0.0;
84 }
86 void
87 SurvRateGroup::stop_adding_regions() {
88 if (_region_num > _stats_arrays_length) {
89 double* old_surv_rate = _surv_rate;
90 double* old_accum_surv_rate_pred = _accum_surv_rate_pred;
91 TruncatedSeq** old_surv_rate_pred = _surv_rate_pred;
93 _surv_rate = NEW_C_HEAP_ARRAY(double, _region_num);
94 _accum_surv_rate_pred = NEW_C_HEAP_ARRAY(double, _region_num);
95 _surv_rate_pred = NEW_C_HEAP_ARRAY(TruncatedSeq*, _region_num);
97 for (size_t i = 0; i < _stats_arrays_length; ++i) {
98 _surv_rate_pred[i] = old_surv_rate_pred[i];
99 }
100 for (size_t i = _stats_arrays_length; i < _region_num; ++i) {
101 _surv_rate_pred[i] = new TruncatedSeq(10);
102 }
104 _stats_arrays_length = _region_num;
106 if (old_surv_rate != NULL) {
107 FREE_C_HEAP_ARRAY(double, old_surv_rate);
108 }
109 if (old_accum_surv_rate_pred != NULL) {
110 FREE_C_HEAP_ARRAY(double, old_accum_surv_rate_pred);
111 }
112 if (old_surv_rate_pred != NULL) {
113 FREE_C_HEAP_ARRAY(TruncatedSeq*, old_surv_rate_pred);
114 }
115 }
117 for (size_t i = 0; i < _stats_arrays_length; ++i) {
118 _surv_rate[i] = 0.0;
119 }
120 }
122 double
123 SurvRateGroup::accum_surv_rate(size_t adjustment) {
124 // we might relax this one in the future...
125 guarantee( adjustment == 0 || adjustment == 1, "pre-condition" );
127 double ret = _accum_surv_rate;
128 if (adjustment > 0) {
129 TruncatedSeq* seq = get_seq(_region_num+1);
130 double surv_rate = _g1p->get_new_prediction(seq);
131 ret += surv_rate;
132 }
134 return ret;
135 }
137 int
138 SurvRateGroup::next_age_index() {
139 TruncatedSeq* seq = get_seq(_region_num);
140 double surv_rate = _g1p->get_new_prediction(seq);
141 _accum_surv_rate += surv_rate;
143 ++_region_num;
144 return (int) ++_all_regions_allocated;
145 }
147 void
148 SurvRateGroup::record_surviving_words(int age_in_group, size_t surv_words) {
149 guarantee( 0 <= age_in_group && (size_t) age_in_group < _region_num,
150 "pre-condition" );
151 guarantee( _surv_rate[age_in_group] <= 0.00001,
152 "should only update each slot once" );
154 double surv_rate = (double) surv_words / (double) HeapRegion::GrainWords;
155 _surv_rate[age_in_group] = surv_rate;
156 _surv_rate_pred[age_in_group]->add(surv_rate);
157 if ((size_t)age_in_group < _summary_surv_rates_len) {
158 _summary_surv_rates[age_in_group]->add(surv_rate);
159 if ((size_t)(age_in_group+1) > _summary_surv_rates_max_len)
160 _summary_surv_rates_max_len = age_in_group+1;
161 }
162 }
164 void
165 SurvRateGroup::all_surviving_words_recorded(bool propagate) {
166 if (propagate && _region_num > 0) { // conservative
167 double surv_rate = _surv_rate_pred[_region_num-1]->last();
168 for (size_t i = _region_num; i < _stats_arrays_length; ++i) {
169 guarantee( _surv_rate[i] <= 0.00001,
170 "the slot should not have been updated" );
171 _surv_rate_pred[i]->add(surv_rate);
172 }
173 }
175 double accum = 0.0;
176 double pred = 0.0;
177 for (size_t i = 0; i < _stats_arrays_length; ++i) {
178 pred = _g1p->get_new_prediction(_surv_rate_pred[i]);
179 if (pred > 1.0) pred = 1.0;
180 accum += pred;
181 _accum_surv_rate_pred[i] = accum;
182 // gclog_or_tty->print_cr("age %3d, accum %10.2lf", i, accum);
183 }
184 _last_pred = pred;
185 }
187 #ifndef PRODUCT
188 void
189 SurvRateGroup::print() {
190 gclog_or_tty->print_cr("Surv Rate Group: %s (%d entries)",
191 _name, _region_num);
192 for (size_t i = 0; i < _region_num; ++i) {
193 gclog_or_tty->print_cr(" age %4d surv rate %6.2lf %% pred %6.2lf %%",
194 i, _surv_rate[i] * 100.0,
195 _g1p->get_new_prediction(_surv_rate_pred[i]) * 100.0);
196 }
197 }
199 void
200 SurvRateGroup::print_surv_rate_summary() {
201 size_t length = _summary_surv_rates_max_len;
202 if (length == 0)
203 return;
205 gclog_or_tty->print_cr("");
206 gclog_or_tty->print_cr("%s Rate Summary (for up to age %d)", _name, length-1);
207 gclog_or_tty->print_cr(" age range survival rate (avg) samples (avg)");
208 gclog_or_tty->print_cr(" ---------------------------------------------------------");
210 size_t index = 0;
211 size_t limit = MIN2((int) length, 10);
212 while (index < limit) {
213 gclog_or_tty->print_cr(" %4d %6.2lf%% %6.2lf",
214 index, _summary_surv_rates[index]->avg() * 100.0,
215 (double) _summary_surv_rates[index]->num());
216 ++index;
217 }
219 gclog_or_tty->print_cr(" ---------------------------------------------------------");
221 int num = 0;
222 double sum = 0.0;
223 int samples = 0;
224 while (index < length) {
225 ++num;
226 sum += _summary_surv_rates[index]->avg() * 100.0;
227 samples += _summary_surv_rates[index]->num();
228 ++index;
230 if (index == length || num % 10 == 0) {
231 gclog_or_tty->print_cr(" %4d .. %4d %6.2lf%% %6.2lf",
232 (index-1) / 10 * 10, index-1, sum / (double) num,
233 (double) samples / (double) num);
234 sum = 0.0;
235 num = 0;
236 samples = 0;
237 }
238 }
240 gclog_or_tty->print_cr(" ---------------------------------------------------------");
241 }
242 #endif // PRODUCT