1.1 --- a/src/share/vm/services/memTracker.cpp Wed Mar 20 08:17:55 2013 +0100
1.2 +++ b/src/share/vm/services/memTracker.cpp Wed Mar 20 09:42:48 2013 -0400
1.3 @@ -68,6 +68,7 @@
1.4 volatile jint MemTracker::_pooled_recorder_count = 0;
1.5 volatile unsigned long MemTracker::_processing_generation = 0;
1.6 volatile bool MemTracker::_worker_thread_idle = false;
1.7 +volatile bool MemTracker::_slowdown_calling_thread = false;
1.8 debug_only(intx MemTracker::_main_thread_tid = 0;)
1.9 NOT_PRODUCT(volatile jint MemTracker::_pending_recorder_count = 0;)
1.10
1.11 @@ -364,6 +365,12 @@
1.12 }
1.13
1.14 if (thread != NULL) {
1.15 + // slow down all calling threads except NMT worker thread, so it
1.16 + // can catch up.
1.17 + if (_slowdown_calling_thread && thread != _worker_thread) {
1.18 + os::yield_all();
1.19 + }
1.20 +
1.21 if (thread->is_Java_thread() && ((JavaThread*)thread)->is_safepoint_visible()) {
1.22 JavaThread* java_thread = (JavaThread*)thread;
1.23 JavaThreadState state = java_thread->thread_state();
1.24 @@ -442,6 +449,7 @@
1.25 #define MAX_SAFEPOINTS_TO_SKIP 128
1.26 #define SAFE_SEQUENCE_THRESHOLD 30
1.27 #define HIGH_GENERATION_THRESHOLD 60
1.28 +#define MAX_RECORDER_THREAD_RATIO 30
1.29
1.30 void MemTracker::sync() {
1.31 assert(_tracking_level > NMT_off, "NMT is not enabled");
1.32 @@ -487,6 +495,13 @@
1.33 pending_recorders = _global_recorder;
1.34 _global_recorder = NULL;
1.35 }
1.36 +
1.37 + // see if NMT has too many outstanding recorder instances, it usually
1.38 + // means that worker thread is lagging behind in processing them.
1.39 + if (!AutoShutdownNMT) {
1.40 + _slowdown_calling_thread = (MemRecorder::_instance_count > MAX_RECORDER_THREAD_RATIO * _thread_count);
1.41 + }
1.42 +
1.43 // check _worker_thread with lock to avoid racing condition
1.44 if (_worker_thread != NULL) {
1.45 _worker_thread->at_sync_point(pending_recorders, InstanceKlass::number_of_instance_classes());
