graal-jvmci-8: src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp comparison

comparison src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp @ 11973:7b06ae405d7b

6990419: CMS Remaining work for 6572569: consistently skewed work distribution in (long) re-mark pauses Reviewed-by: rasbold, tschatzl, jmasa Contributed-by: yamauchi@google.com

author	jmasa
date	Tue, 23 Jul 2013 09:49:11 -0700
parents	71180a6e5080
children	ca9dedeebdec

comparison

equal deleted inserted replaced

-:2285b4a0a4e6
+:7b06ae405d7b
 // Construct the is_alive_closure with _span & markBitMap
 _is_alive_closure(_span, &_markBitMap),
 _restart_addr(NULL),
 _overflow_list(NULL),
 _stats(cmsGen),
+_eden_chunk_lock(new Mutex(Mutex::leaf + 1, "CMS_eden_chunk_lock", true)),
 _eden_chunk_array(NULL),     // may be set in ctor body
 _eden_chunk_capacity(0),     // -- ditto --
 _eden_chunk_index(0),        // -- ditto --
 _survivor_plab_array(NULL),  // -- ditto --
 _survivor_chunk_array(NULL), // -- ditto --
 // For a mark-sweep, compute_new_size() will be called
 // in the heap's do_collection() method.
 }
+void CMSCollector::print_eden_and_survivor_chunk_arrays() {
+DefNewGeneration* dng = _young_gen->as_DefNewGeneration();
+EdenSpace* eden_space = dng->eden();
+ContiguousSpace* from_space = dng->from();
+ContiguousSpace* to_space   = dng->to();
+// Eden
+if (_eden_chunk_array != NULL) {
+gclog_or_tty->print_cr("eden " PTR_FORMAT "-" PTR_FORMAT "-" PTR_FORMAT "(" SIZE_FORMAT ")",
+eden_space->bottom(), eden_space->top(),
+eden_space->end(), eden_space->capacity());
+gclog_or_tty->print_cr("_eden_chunk_index=" SIZE_FORMAT ", "
+"_eden_chunk_capacity=" SIZE_FORMAT,
+_eden_chunk_index, _eden_chunk_capacity);
+for (size_t i = 0; i < _eden_chunk_index; i++) {
+gclog_or_tty->print_cr("_eden_chunk_array[" SIZE_FORMAT "]=" PTR_FORMAT,
+i, _eden_chunk_array[i]);
+}
+}
+// Survivor
+if (_survivor_chunk_array != NULL) {
+gclog_or_tty->print_cr("survivor " PTR_FORMAT "-" PTR_FORMAT "-" PTR_FORMAT "(" SIZE_FORMAT ")",
+from_space->bottom(), from_space->top(),
+from_space->end(), from_space->capacity());
+gclog_or_tty->print_cr("_survivor_chunk_index=" SIZE_FORMAT ", "
+"_survivor_chunk_capacity=" SIZE_FORMAT,
+_survivor_chunk_index, _survivor_chunk_capacity);
+for (size_t i = 0; i < _survivor_chunk_index; i++) {
+gclog_or_tty->print_cr("_survivor_chunk_array[" SIZE_FORMAT "]=" PTR_FORMAT,
+i, _survivor_chunk_array[i]);
+}
+}
+}
 void CMSCollector::getFreelistLocks() const {
 // Get locks for all free lists in all generations that this
 // collector is responsible for
 _cmsGen->freelistLock()->lock_without_safepoint_check();
 }
 ClassLoaderDataGraph::remember_new_clds(true);
 // Whenever a CLD is found, it will be claimed before proceeding to mark
 // the klasses. The claimed marks need to be cleared before marking starts.
 ClassLoaderDataGraph::clear_claimed_marks();
+if (CMSPrintEdenSurvivorChunks) {
+print_eden_and_survivor_chunk_arrays();
+}
 CMKlassClosure klass_closure(&notOlder);
 {
 COMPILER2_PRESENT(DerivedPointerTableDeactivate dpt_deact;)
 gch->rem_set()->prepare_for_younger_refs_iterate(false); // Not parallel.
 assert(Thread::current()->is_ConcurrentGC_thread(), "Wrong thread");
 verify_work_stacks_empty();
 verify_overflow_empty();
 _abort_preclean = false;
 if (CMSPrecleaningEnabled) {
-_eden_chunk_index = 0;
+if (!CMSEdenChunksRecordAlways) {
+_eden_chunk_index = 0;
+}
 size_t used = get_eden_used();
 size_t capacity = get_eden_capacity();
 // Don't start sampling unless we will get sufficiently
 // many samples.
 if (used < (capacity/(CMSScheduleRemarkSamplingRatio * 100)
 assert(ConcurrentMarkSweepThread::cms_thread_has_cms_token(),
 "Should collect samples while holding CMS token");
 if (!_start_sampling) {
 return;
 }
-if (_eden_chunk_array) {
+// When CMSEdenChunksRecordAlways is true, the eden chunk array
+// is populated by the young generation.
+if (_eden_chunk_array != NULL && !CMSEdenChunksRecordAlways) {
 if (_eden_chunk_index < _eden_chunk_capacity) {
 _eden_chunk_array[_eden_chunk_index] = *_top_addr;   // take sample
 assert(_eden_chunk_array[_eden_chunk_index] <= *_end_addr,
 "Unexpected state of Eden");
 // We'd like to check that what we just sampled is an oop-start address;
 // so here just in case a scavenge did not happen.
 gch->ensure_parsability(false);  // fill TLAB's, but no need to retire them
 // Update the saved marks which may affect the root scans.
 gch->save_marks();
+if (CMSPrintEdenSurvivorChunks) {
+print_eden_and_survivor_chunk_arrays();
+}
 {
 COMPILER2_PRESENT(DerivedPointerTableDeactivate dpt_deact;)
 // Note on the role of the mod union table:
 // Since the marker in "markFromRoots" marks concurrently with
 gclog_or_tty->print("\n\t(%d: stole %d oops)", i, num_steals);
 }
 )
 assert(work_q->size() == 0 && _collector->overflow_list_is_empty(),
 "Else our work is not yet done");
+}
+// Record object boundaries in _eden_chunk_array by sampling the eden
+// top in the slow-path eden object allocation code path and record
+// the boundaries, if CMSEdenChunksRecordAlways is true. If
+// CMSEdenChunksRecordAlways is false, we use the other asynchronous
+// sampling in sample_eden() that activates during the part of the
+// preclean phase.
+void CMSCollector::sample_eden_chunk() {
+if (CMSEdenChunksRecordAlways && _eden_chunk_array != NULL) {
+if (_eden_chunk_lock->try_lock()) {
+// Record a sample. This is the critical section. The contents
+// of the _eden_chunk_array have to be non-decreasing in the
+// address order.
+_eden_chunk_array[_eden_chunk_index] = *_top_addr;
+assert(_eden_chunk_array[_eden_chunk_index] <= *_end_addr,
+"Unexpected state of Eden");
+if (_eden_chunk_index == 0 ||
+((_eden_chunk_array[_eden_chunk_index] > _eden_chunk_array[_eden_chunk_index-1]) &&
+(pointer_delta(_eden_chunk_array[_eden_chunk_index],
+_eden_chunk_array[_eden_chunk_index-1]) >= CMSSamplingGrain))) {
+_eden_chunk_index++;  // commit sample
+}
+_eden_chunk_lock->unlock();
+}
+}
 }
 // Return a thread-local PLAB recording array, as appropriate.
 void* CMSCollector::get_data_recorder(int thr_num) {
 if (_survivor_plab_array != NULL &&
 default:
 ShouldNotReachHere();
 }
 }

Mercurial > hg > graal-jvmci-8

comparison src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp @ 11973:7b06ae405d7b