1 /*
2 * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
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 *
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
21 * questions.
22 *
23 */
24 #include "precompiled.hpp"
25
26 #include "runtime/atomic.hpp"
27 #include "runtime/interfaceSupport.hpp"
28 #include "runtime/mutexLocker.hpp"
29 #include "runtime/safepoint.hpp"
30 #include "runtime/threadCritical.hpp"
31 #include "runtime/vm_operations.hpp"
32 #include "services/memPtr.hpp"
33 #include "services/memReporter.hpp"
34 #include "services/memTracker.hpp"
35 #include "utilities/decoder.hpp"
36 #include "utilities/globalDefinitions.hpp"
37
38 bool NMT_track_callsite = false;
39
40 // walk all 'known' threads at NMT sync point, and collect their recorders
41 void SyncThreadRecorderClosure::do_thread(Thread* thread) {
42 assert(SafepointSynchronize::is_at_safepoint(), "Safepoint required");
43 if (thread->is_Java_thread()) {
44 JavaThread* javaThread = (JavaThread*)thread;
45 MemRecorder* recorder = javaThread->get_recorder();
46 if (recorder != NULL) {
47 MemTracker::enqueue_pending_recorder(recorder);
48 javaThread->set_recorder(NULL);
49 }
50 }
51 _thread_count ++;
52 }
53
54
55 MemRecorder* MemTracker::_global_recorder = NULL;
56 MemSnapshot* MemTracker::_snapshot = NULL;
57 MemBaseline MemTracker::_baseline;
58 Mutex* MemTracker::_query_lock = NULL;
59 volatile MemRecorder* MemTracker::_merge_pending_queue = NULL;
60 volatile MemRecorder* MemTracker::_pooled_recorders = NULL;
61 MemTrackWorker* MemTracker::_worker_thread = NULL;
62 int MemTracker::_sync_point_skip_count = 0;
63 MemTracker::NMTLevel MemTracker::_tracking_level = MemTracker::NMT_off;
64 volatile MemTracker::NMTStates MemTracker::_state = NMT_uninited;
65 MemTracker::ShutdownReason MemTracker::_reason = NMT_shutdown_none;
66 int MemTracker::_thread_count = 255;
67 volatile jint MemTracker::_pooled_recorder_count = 0;
68 volatile unsigned long MemTracker::_processing_generation = 0;
69 volatile bool MemTracker::_worker_thread_idle = false;
70 debug_only(intx MemTracker::_main_thread_tid = 0;)
71 NOT_PRODUCT(volatile jint MemTracker::_pending_recorder_count = 0;)
72
73 void MemTracker::init_tracking_options(const char* option_line) {
74 _tracking_level = NMT_off;
75 if (strcmp(option_line, "=summary") == 0) {
76 _tracking_level = NMT_summary;
77 } else if (strcmp(option_line, "=detail") == 0) {
78 _tracking_level = NMT_detail;
79 } else if (strcmp(option_line, "=off") != 0) {
80 vm_exit_during_initialization("Syntax error, expecting -XX:NativeMemoryTracking=[off|summary|detail]", NULL);
81 }
82 }
83
84 // first phase of bootstrapping, when VM is still in single-threaded mode.
85 void MemTracker::bootstrap_single_thread() {
86 if (_tracking_level > NMT_off) {
87 assert(_state == NMT_uninited, "wrong state");
88
89 // NMT is not supported with UseMallocOnly is on. NMT can NOT
90 // handle the amount of malloc data without significantly impacting
91 // runtime performance when this flag is on.
92 if (UseMallocOnly) {
93 shutdown(NMT_use_malloc_only);
94 return;
95 }
96
97 _query_lock = new (std::nothrow) Mutex(Monitor::max_nonleaf, "NMT_queryLock");
98 if (_query_lock == NULL) {
99 shutdown(NMT_out_of_memory);
100 return;
101 }
102
103 debug_only(_main_thread_tid = os::current_thread_id();)
104 _state = NMT_bootstrapping_single_thread;
105 NMT_track_callsite = (_tracking_level == NMT_detail && can_walk_stack());
106 }
107 }
108
109 // second phase of bootstrapping, when VM is about to or already entered multi-theaded mode.
110 void MemTracker::bootstrap_multi_thread() {
111 if (_tracking_level > NMT_off && _state == NMT_bootstrapping_single_thread) {
112 // create nmt lock for multi-thread execution
113 assert(_main_thread_tid == os::current_thread_id(), "wrong thread");
114 _state = NMT_bootstrapping_multi_thread;
115 NMT_track_callsite = (_tracking_level == NMT_detail && can_walk_stack());
116 }
117 }
118
119 // fully start nmt
120 void MemTracker::start() {
121 // Native memory tracking is off from command line option
122 if (_tracking_level == NMT_off || shutdown_in_progress()) return;
123
124 assert(_main_thread_tid == os::current_thread_id(), "wrong thread");
125 assert(_state == NMT_bootstrapping_multi_thread, "wrong state");
126
127 _snapshot = new (std::nothrow)MemSnapshot();
128 if (_snapshot != NULL && !_snapshot->out_of_memory()) {
129 if (start_worker()) {
130 _state = NMT_started;
131 NMT_track_callsite = (_tracking_level == NMT_detail && can_walk_stack());
132 return;
133 }
134 }
135
136 // fail to start native memory tracking, shut it down
137 shutdown(NMT_initialization);
138 }
139
140 /**
141 * Shutting down native memory tracking.
142 * We can not shutdown native memory tracking immediately, so we just
143 * setup shutdown pending flag, every native memory tracking component
144 * should orderly shut itself down.
145 *
146 * The shutdown sequences:
147 * 1. MemTracker::shutdown() sets MemTracker to shutdown pending state
148 * 2. Worker thread calls MemTracker::final_shutdown(), which transites
149 * MemTracker to final shutdown state.
150 * 3. At sync point, MemTracker does final cleanup, before sets memory
151 * tracking level to off to complete shutdown.
152 */
153 void MemTracker::shutdown(ShutdownReason reason) {
154 if (_tracking_level == NMT_off) return;
155
156 if (_state <= NMT_bootstrapping_single_thread) {
157 // we still in single thread mode, there is not contention
158 _state = NMT_shutdown_pending;
159 _reason = reason;
160 } else {
161 // we want to know who initialized shutdown
162 if ((jint)NMT_started == Atomic::cmpxchg((jint)NMT_shutdown_pending,
163 (jint*)&_state, (jint)NMT_started)) {
164 _reason = reason;
165 }
166 }
167 }
168
169 // final phase of shutdown
170 void MemTracker::final_shutdown() {
171 // delete all pending recorders and pooled recorders
172 delete_all_pending_recorders();
173 delete_all_pooled_recorders();
174
175 {
176 // shared baseline and snapshot are the only objects needed to
177 // create query results
178 MutexLockerEx locker(_query_lock, true);
179 // cleanup baseline data and snapshot
180 _baseline.clear();
181 MemSnapshot* the_snapshot = _snapshot;
182 _snapshot = NULL;
183 delete the_snapshot;
184 }
185
186 // shutdown shared decoder instance, since it is only
187 // used by native memory tracking so far.
188 Decoder::shutdown();
189
190 MemTrackWorker* worker = NULL;
191 {
192 ThreadCritical tc;
193 // can not delete worker inside the thread critical
194 if (_worker_thread != NULL && Thread::current() == _worker_thread) {
195 worker = _worker_thread;
196 _worker_thread = NULL;
197 }
198 }
199 if (worker != NULL) {
200 delete worker;
201 }
202 _state = NMT_final_shutdown;
203 }
204
205 // delete all pooled recorders
206 void MemTracker::delete_all_pooled_recorders() {
207 // free all pooled recorders
208 volatile MemRecorder* cur_head = _pooled_recorders;
209 if (cur_head != NULL) {
210 MemRecorder* null_ptr = NULL;
211 while (cur_head != NULL && (void*)cur_head != Atomic::cmpxchg_ptr((void*)null_ptr,
212 (void*)&_pooled_recorders, (void*)cur_head)) {
213 cur_head = _pooled_recorders;
214 }
215 if (cur_head != NULL) {
216 delete cur_head;
217 _pooled_recorder_count = 0;
218 }
219 }
220 }
221
222 // delete all recorders in pending queue
223 void MemTracker::delete_all_pending_recorders() {
224 // free all pending recorders
225 MemRecorder* pending_head = get_pending_recorders();
226 if (pending_head != NULL) {
227 delete pending_head;
228 }
229 }
230
231 /*
232 * retrieve per-thread recorder of specified thread.
233 * if thread == NULL, it means global recorder
234 */
235 MemRecorder* MemTracker::get_thread_recorder(JavaThread* thread) {
236 if (shutdown_in_progress()) return NULL;
237
238 MemRecorder* rc;
239 if (thread == NULL) {
240 rc = _global_recorder;
241 } else {
242 rc = thread->get_recorder();
243 }
244
245 if (rc != NULL && rc->is_full()) {
246 enqueue_pending_recorder(rc);
247 rc = NULL;
248 }
249
250 if (rc == NULL) {
251 rc = get_new_or_pooled_instance();
252 if (thread == NULL) {
253 _global_recorder = rc;
254 } else {
255 thread->set_recorder(rc);
256 }
257 }
258 return rc;
259 }
260
261 /*
262 * get a per-thread recorder from pool, or create a new one if
263 * there is not one available.
264 */
265 MemRecorder* MemTracker::get_new_or_pooled_instance() {
266 MemRecorder* cur_head = const_cast<MemRecorder*> (_pooled_recorders);
267 if (cur_head == NULL) {
268 MemRecorder* rec = new (std::nothrow)MemRecorder();
269 if (rec == NULL || rec->out_of_memory()) {
270 shutdown(NMT_out_of_memory);
271 if (rec != NULL) {
272 delete rec;
273 rec = NULL;
274 }
275 }
276 return rec;
277 } else {
278 MemRecorder* next_head = cur_head->next();
279 if ((void*)cur_head != Atomic::cmpxchg_ptr((void*)next_head, (void*)&_pooled_recorders,
280 (void*)cur_head)) {
281 return get_new_or_pooled_instance();
282 }
283 cur_head->set_next(NULL);
284 Atomic::dec(&_pooled_recorder_count);
285 cur_head->set_generation();
286 return cur_head;
287 }
288 }
289
290 /*
291 * retrieve all recorders in pending queue, and empty the queue
292 */
293 MemRecorder* MemTracker::get_pending_recorders() {
294 MemRecorder* cur_head = const_cast<MemRecorder*>(_merge_pending_queue);
295 MemRecorder* null_ptr = NULL;
296 while ((void*)cur_head != Atomic::cmpxchg_ptr((void*)null_ptr, (void*)&_merge_pending_queue,
297 (void*)cur_head)) {
298 cur_head = const_cast<MemRecorder*>(_merge_pending_queue);
299 }
300 NOT_PRODUCT(Atomic::store(0, &_pending_recorder_count));
301 return cur_head;
302 }
303
304 /*
305 * release a recorder to recorder pool.
306 */
307 void MemTracker::release_thread_recorder(MemRecorder* rec) {
308 assert(rec != NULL, "null recorder");
309 // we don't want to pool too many recorders
310 rec->set_next(NULL);
311 if (shutdown_in_progress() || _pooled_recorder_count > _thread_count * 2) {
312 delete rec;
313 return;
314 }
315
316 rec->clear();
317 MemRecorder* cur_head = const_cast<MemRecorder*>(_pooled_recorders);
318 rec->set_next(cur_head);
319 while ((void*)cur_head != Atomic::cmpxchg_ptr((void*)rec, (void*)&_pooled_recorders,
320 (void*)cur_head)) {
321 cur_head = const_cast<MemRecorder*>(_pooled_recorders);
322 rec->set_next(cur_head);
323 }
324 Atomic::inc(&_pooled_recorder_count);
325 }
326
327 /*
328 * This is the most important method in whole nmt implementation.
329 *
330 * Create a memory record.
331 * 1. When nmt is in single-threaded bootstrapping mode, no lock is needed as VM
332 * still in single thread mode.
333 * 2. For all threads other than JavaThread, ThreadCritical is needed
334 * to write to recorders to global recorder.
335 * 3. For JavaThreads that are not longer visible by safepoint, also
336 * need to take ThreadCritical and records are written to global
337 * recorders, since these threads are NOT walked by Threads.do_thread().
338 * 4. JavaThreads that are running in native state, have to transition
339 * to VM state before writing to per-thread recorders.
340 * 5. JavaThreads that are running in VM state do not need any lock and
341 * records are written to per-thread recorders.
342 * 6. For a thread has yet to attach VM 'Thread', they need to take
343 * ThreadCritical to write to global recorder.
344 *
345 * Important note:
346 * NO LOCK should be taken inside ThreadCritical lock !!!
347 */
348 void MemTracker::create_memory_record(address addr, MEMFLAGS flags,
349 size_t size, address pc, Thread* thread) {
350 assert(addr != NULL, "Sanity check");
351 if (!shutdown_in_progress()) {
352 // single thread, we just write records direct to global recorder,'
353 // with any lock
354 if (_state == NMT_bootstrapping_single_thread) {
355 assert(_main_thread_tid == os::current_thread_id(), "wrong thread");
356 thread = NULL;
357 } else {
358 if (thread == NULL) {
359 // don't use Thread::current(), since it is possible that
360 // the calling thread has yet to attach to VM 'Thread',
361 // which will result assertion failure
362 thread = ThreadLocalStorage::thread();
363 }
364 }
365
366 if (thread != NULL) {
367 if (thread->is_Java_thread() && ((JavaThread*)thread)->is_safepoint_visible()) {
368 JavaThread* java_thread = (JavaThread*)thread;
369 JavaThreadState state = java_thread->thread_state();
370 if (SafepointSynchronize::safepoint_safe(java_thread, state)) {
371 // JavaThreads that are safepoint safe, can run through safepoint,
372 // so ThreadCritical is needed to ensure no threads at safepoint create
373 // new records while the records are being gathered and the sequence number is changing
374 ThreadCritical tc;
375 create_record_in_recorder(addr, flags, size, pc, java_thread);
376 } else {
377 create_record_in_recorder(addr, flags, size, pc, java_thread);
378 }
379 } else {
380 // other threads, such as worker and watcher threads, etc. need to
381 // take ThreadCritical to write to global recorder
382 ThreadCritical tc;
383 create_record_in_recorder(addr, flags, size, pc, NULL);
384 }
385 } else {
386 if (_state == NMT_bootstrapping_single_thread) {
387 // single thread, no lock needed
388 create_record_in_recorder(addr, flags, size, pc, NULL);
389 } else {
390 // for thread has yet to attach VM 'Thread', we can not use VM mutex.
391 // use native thread critical instead
392 ThreadCritical tc;
393 create_record_in_recorder(addr, flags, size, pc, NULL);
394 }
395 }
396 }
397 }
398
399 // write a record to proper recorder. No lock can be taken from this method
400 // down.
401 void MemTracker::create_record_in_recorder(address addr, MEMFLAGS flags,
402 size_t size, address pc, JavaThread* thread) {
403
404 MemRecorder* rc = get_thread_recorder(thread);
405 if (rc != NULL) {
406 rc->record(addr, flags, size, pc);
407 }
408 }
409
410 /**
411 * enqueue a recorder to pending queue
412 */
413 void MemTracker::enqueue_pending_recorder(MemRecorder* rec) {
414 assert(rec != NULL, "null recorder");
415
416 // we are shutting down, so just delete it
417 if (shutdown_in_progress()) {
418 rec->set_next(NULL);
419 delete rec;
420 return;
421 }
422
423 MemRecorder* cur_head = const_cast<MemRecorder*>(_merge_pending_queue);
424 rec->set_next(cur_head);
425 while ((void*)cur_head != Atomic::cmpxchg_ptr((void*)rec, (void*)&_merge_pending_queue,
426 (void*)cur_head)) {
427 cur_head = const_cast<MemRecorder*>(_merge_pending_queue);
428 rec->set_next(cur_head);
429 }
430 NOT_PRODUCT(Atomic::inc(&_pending_recorder_count);)
431 }
432
433 /*
434 * The method is called at global safepoint
435 * during it synchronization process.
436 * 1. enqueue all JavaThreads' per-thread recorders
437 * 2. enqueue global recorder
438 * 3. retrieve all pending recorders
439 * 4. reset global sequence number generator
440 * 5. call worker's sync
441 */
442 #define MAX_SAFEPOINTS_TO_SKIP 128
443 #define SAFE_SEQUENCE_THRESHOLD 30
444 #define HIGH_GENERATION_THRESHOLD 60
445
446 void MemTracker::sync() {
447 assert(_tracking_level > NMT_off, "NMT is not enabled");
448 assert(SafepointSynchronize::is_at_safepoint(), "Safepoint required");
449
450 // Some GC tests hit large number of safepoints in short period of time
451 // without meaningful activities. We should prevent going to
452 // sync point in these cases, which can potentially exhaust generation buffer.
453 // Here is the factots to determine if we should go into sync point:
454 // 1. not to overflow sequence number
455 // 2. if we are in danger to overflow generation buffer
456 // 3. how many safepoints we already skipped sync point
457 if (_state == NMT_started) {
458 // worker thread is not ready, no one can manage generation
459 // buffer, so skip this safepoint
460 if (_worker_thread == NULL) return;
461
462 if (_sync_point_skip_count < MAX_SAFEPOINTS_TO_SKIP) {
463 int per_seq_in_use = SequenceGenerator::peek() * 100 / max_jint;
464 int per_gen_in_use = _worker_thread->generations_in_use() * 100 / MAX_GENERATIONS;
465 if (per_seq_in_use < SAFE_SEQUENCE_THRESHOLD && per_gen_in_use >= HIGH_GENERATION_THRESHOLD) {
466 _sync_point_skip_count ++;
467 return;
468 }
469 }
470 _sync_point_skip_count = 0;
471 {
472 // This method is running at safepoint, with ThreadCritical lock,
473 // it should guarantee that NMT is fully sync-ed.
474 ThreadCritical tc;
475
476 SequenceGenerator::reset();
477
478 // walk all JavaThreads to collect recorders
479 SyncThreadRecorderClosure stc;
480 Threads::threads_do(&stc);
481
482 _thread_count = stc.get_thread_count();
483 MemRecorder* pending_recorders = get_pending_recorders();
484
485 if (_global_recorder != NULL) {
486 _global_recorder->set_next(pending_recorders);
487 pending_recorders = _global_recorder;
488 _global_recorder = NULL;
489 }
490 // check _worker_thread with lock to avoid racing condition
491 if (_worker_thread != NULL) {
492 _worker_thread->at_sync_point(pending_recorders);
493 }
494
495 assert(SequenceGenerator::peek() == 1, "Should not have memory activities during sync-point");
496 }
497 }
498
499 // now, it is the time to shut whole things off
500 if (_state == NMT_final_shutdown) {
501 // walk all JavaThreads to delete all recorders
502 SyncThreadRecorderClosure stc;
503 Threads::threads_do(&stc);
504 // delete global recorder
505 {
506 ThreadCritical tc;
507 if (_global_recorder != NULL) {
508 delete _global_recorder;
509 _global_recorder = NULL;
510 }
511 }
512 MemRecorder* pending_recorders = get_pending_recorders();
513 if (pending_recorders != NULL) {
514 delete pending_recorders;
515 }
516 // try at a later sync point to ensure MemRecorder instance drops to zero to
517 // completely shutdown NMT
518 if (MemRecorder::_instance_count == 0) {
519 _state = NMT_shutdown;
520 _tracking_level = NMT_off;
521 }
522 }
523 }
524
525 /*
526 * Start worker thread.
527 */
528 bool MemTracker::start_worker() {
529 assert(_worker_thread == NULL, "Just Check");
530 _worker_thread = new (std::nothrow) MemTrackWorker();
531 if (_worker_thread == NULL || _worker_thread->has_error()) {
532 shutdown(NMT_initialization);
533 return false;
534 }
535 _worker_thread->start();
536 return true;
537 }
538
539 /*
540 * We need to collect a JavaThread's per-thread recorder
541 * before it exits.
542 */
543 void MemTracker::thread_exiting(JavaThread* thread) {
544 if (is_on()) {
545 MemRecorder* rec = thread->get_recorder();
546 if (rec != NULL) {
547 enqueue_pending_recorder(rec);
548 thread->set_recorder(NULL);
549 }
550 }
551 }
552
553 // baseline current memory snapshot
554 bool MemTracker::baseline() {
555 MutexLockerEx lock(_query_lock, true);
556 MemSnapshot* snapshot = get_snapshot();
557 if (snapshot != NULL) {
558 return _baseline.baseline(*snapshot, false);
559 }
560 return false;
561 }
562
563 // print memory usage from current snapshot
564 bool MemTracker::print_memory_usage(BaselineOutputer& out, size_t unit, bool summary_only) {
565 MemBaseline baseline;
566 MutexLockerEx lock(_query_lock, true);
567 MemSnapshot* snapshot = get_snapshot();
568 if (snapshot != NULL && baseline.baseline(*snapshot, summary_only)) {
569 BaselineReporter reporter(out, unit);
570 reporter.report_baseline(baseline, summary_only);
571 return true;
572 }
573 return false;
574 }
575
576 // Whitebox API for blocking until the current generation of NMT data has been merged
577 bool MemTracker::wbtest_wait_for_data_merge() {
578 MutexLockerEx lock(_query_lock, true);
579 assert(_worker_thread != NULL, "Invalid query");
580 // the generation at query time, so NMT will spin till this generation is processed
581 unsigned long generation_at_query_time = SequenceGenerator::current_generation();
582 unsigned long current_processing_generation = _processing_generation;
583 // if generation counter overflown
584 bool generation_overflown = (generation_at_query_time < current_processing_generation);
585 long generations_to_wrap = MAX_UNSIGNED_LONG - current_processing_generation;
586 // spin
587 while (!shutdown_in_progress()) {
588 if (!generation_overflown) {
589 if (current_processing_generation > generation_at_query_time) {
590 break;
591 }
592 } else {
593 assert(generations_to_wrap >= 0, "Sanity check");
594 long current_generations_to_wrap = MAX_UNSIGNED_LONG - current_processing_generation;
595 assert(current_generations_to_wrap >= 0, "Sanity check");
596 // to overflow an unsigned long should take long time, so to_wrap check should be sufficient
597 if (current_generations_to_wrap > generations_to_wrap &&
598 current_processing_generation > generation_at_query_time) {
599 break;
600 }
601 }
602
603 // if worker thread is idle, but generation is not advancing, that means
604 // there is not safepoint to let NMT advance generation, force one.
605 if (_worker_thread_idle) {
606 VM_ForceSafepoint vfs;
607 VMThread::execute(&vfs);
608 }
609 MemSnapshot* snapshot = get_snapshot();
610 if (snapshot == NULL) {
611 return false;
612 }
613 snapshot->wait(1000);
614 current_processing_generation = _processing_generation;
615 }
616 return true;
617 }
618
619 // compare memory usage between current snapshot and baseline
620 bool MemTracker::compare_memory_usage(BaselineOutputer& out, size_t unit, bool summary_only) {
621 MutexLockerEx lock(_query_lock, true);
622 if (_baseline.baselined()) {
623 MemBaseline baseline;
624 MemSnapshot* snapshot = get_snapshot();
625 if (snapshot != NULL && baseline.baseline(*snapshot, summary_only)) {
626 BaselineReporter reporter(out, unit);
627 reporter.diff_baselines(baseline, _baseline, summary_only);
628 return true;
629 }
630 }
631 return false;
632 }
633
634 #ifndef PRODUCT
635 void MemTracker::walk_stack(int toSkip, char* buf, int len) {
636 int cur_len = 0;
637 char tmp[1024];
638 address pc;
639
640 while (cur_len < len) {
641 pc = os::get_caller_pc(toSkip + 1);
642 if (pc != NULL && os::dll_address_to_function_name(pc, tmp, sizeof(tmp), NULL)) {
643 jio_snprintf(&buf[cur_len], (len - cur_len), "%s\n", tmp);
644 cur_len = (int)strlen(buf);
645 } else {
646 buf[cur_len] = '\0';
647 break;
648 }
649 toSkip ++;
650 }
651 }
652
653 void MemTracker::print_tracker_stats(outputStream* st) {
654 st->print_cr("\nMemory Tracker Stats:");
655 st->print_cr("\tMax sequence number = %d", SequenceGenerator::max_seq_num());
656 st->print_cr("\tthead count = %d", _thread_count);
657 st->print_cr("\tArena instance = %d", Arena::_instance_count);
658 st->print_cr("\tpooled recorder count = %d", _pooled_recorder_count);
659 st->print_cr("\tqueued recorder count = %d", _pending_recorder_count);
660 st->print_cr("\tmemory recorder instance count = %d", MemRecorder::_instance_count);
661 if (_worker_thread != NULL) {
662 st->print_cr("\tWorker thread:");
663 st->print_cr("\t\tSync point count = %d", _worker_thread->_sync_point_count);
664 st->print_cr("\t\tpending recorder count = %d", _worker_thread->count_pending_recorders());
665 st->print_cr("\t\tmerge count = %d", _worker_thread->_merge_count);
666 } else {
667 st->print_cr("\tWorker thread is not started");
668 }
669 st->print_cr(" ");
670
671 if (_snapshot != NULL) {
672 _snapshot->print_snapshot_stats(st);
673 } else {
674 st->print_cr("No snapshot");
675 }
676 }
677 #endif
678