8240215: Shenandoah: remove ShenandoahAllocationTrace

Reviewed-by: rkennke

Author: shipilev

src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp

@@ -361,10 +361,6 @@ jint ShenandoahHeap::initialize() {
   ShenandoahStringDedup::initialize();
   ShenandoahCodeRoots::initialize();
 
-  if (ShenandoahAllocationTrace) {
-    _alloc_tracker = new ShenandoahAllocTracker();
-  }
-
   if (ShenandoahPacing) {
     _pacer = new ShenandoahPacer(this);
     _pacer->setup_for_idle();
@@ -449,7 +445,6 @@ ShenandoahHeap::ShenandoahHeap(ShenandoahCollectorPolicy* policy) :
   _full_gc(new ShenandoahMarkCompact()),
   _pacer(NULL),
   _verifier(NULL),
-  _alloc_tracker(NULL),
   _phase_timings(NULL),
   _monitoring_support(NULL),
   _memory_pool(NULL),
@@ -797,8 +792,6 @@ ShenandoahHeap* ShenandoahHeap::heap_no_check() {
 }
 
 HeapWord* ShenandoahHeap::allocate_memory(ShenandoahAllocRequest& req) {
-  ShenandoahAllocTrace trace_alloc(req.size(), req.type());
-
   intptr_t pacer_epoch = 0;
   bool in_new_region = false;
   HeapWord* result = NULL;
@@ -1202,13 +1195,6 @@ void ShenandoahHeap::print_tracing_info() const {
 
     ls.cr();
     ls.cr();
-
-    if (ShenandoahAllocationTrace) {
-      assert(alloc_tracker() != NULL, "Must be");
-      alloc_tracker()->print_on(&ls);
-    } else {
-      ls.print_cr("  Allocation tracing is disabled, use -XX:+ShenandoahAllocationTrace to enable.");
-    }
   }
 }
 

src/hotspot/share/gc/shenandoah/shenandoahHeap.hpp

@@ -458,7 +458,6 @@ class ShenandoahHeap : public CollectedHeap {
   ShenandoahPacer*           _pacer;
   ShenandoahVerifier*        _verifier;
 
-  ShenandoahAllocTracker*    _alloc_tracker;
   ShenandoahPhaseTimings*    _phase_timings;
 
   ShenandoahControlThread*   control_thread()          { return _control_thread;    }
@@ -474,7 +473,6 @@ class ShenandoahHeap : public CollectedHeap {
   ShenandoahPacer*           pacer()             const { return _pacer;             }
 
   ShenandoahPhaseTimings*    phase_timings()     const { return _phase_timings;     }
-  ShenandoahAllocTracker*    alloc_tracker()     const { return _alloc_tracker;     }
 
   ShenandoahVerifier*        verifier();
 

src/hotspot/share/gc/shenandoah/shenandoahUtils.cpp

@@ -138,33 +138,6 @@ bool ShenandoahGCPhase::is_root_work_phase() {
   }
 }
 
-ShenandoahAllocTrace::ShenandoahAllocTrace(size_t words_size, ShenandoahAllocRequest::Type alloc_type) {
-  if (ShenandoahAllocationTrace) {
-    _start = os::elapsedTime();
-    _size = words_size;
-    _alloc_type = alloc_type;
-  } else {
-    _start = 0;
-    _size = 0;
-    _alloc_type = ShenandoahAllocRequest::Type(0);
-  }
-}
-
-ShenandoahAllocTrace::~ShenandoahAllocTrace() {
-  if (ShenandoahAllocationTrace) {
-    double stop = os::elapsedTime();
-    double duration_sec = stop - _start;
-    double duration_us = duration_sec * 1000000;
-    ShenandoahAllocTracker* tracker = ShenandoahHeap::heap()->alloc_tracker();
-    assert(tracker != NULL, "Must be");
-    tracker->record_alloc_latency(_size, _alloc_type, duration_us);
-    if (duration_us > ShenandoahAllocationStallThreshold) {
-      log_warning(gc)("Allocation stall: %.0f us (threshold: " INTX_FORMAT " us)",
-                      duration_us, ShenandoahAllocationStallThreshold);
-    }
-  }
-}
-
 ShenandoahWorkerSession::ShenandoahWorkerSession(uint worker_id) : _worker_id(worker_id) {
   Thread* thr = Thread::current();
   assert(ShenandoahThreadLocalData::worker_id(thr) == ShenandoahThreadLocalData::INVALID_WORKER_ID, "Already set");

src/hotspot/share/gc/shenandoah/shenandoahUtils.hpp

@@ -87,16 +87,6 @@ class ShenandoahGCPauseMark : public StackObj {
   ~ShenandoahGCPauseMark();
 };
 
-class ShenandoahAllocTrace : public StackObj {
-private:
-  double _start;
-  size_t _size;
-  ShenandoahAllocRequest::Type _alloc_type;
-public:
-  ShenandoahAllocTrace(size_t words_size, ShenandoahAllocRequest::Type alloc_type);
-  ~ShenandoahAllocTrace();
-};
-
 class ShenandoahSafepoint : public AllStatic {
 public:
   // check if Shenandoah GC safepoint is in progress

src/hotspot/share/gc/shenandoah/shenandoah_globals.hpp

@@ -235,16 +235,6 @@
           "evacuation reserve/waste is incorrect, at the risk that "        \
           "application allocations run out of memory too early.")           \
                                                                             \
-  diagnostic(bool, ShenandoahAllocationTrace, false,                        \
-          "Trace allocation latencies and stalls. Can be expensive when "   \
-          "lots of allocations happen, and may introduce scalability "      \
-          "bottlenecks.")                                                   \
-                                                                            \
-  diagnostic(intx, ShenandoahAllocationStallThreshold, 10000,               \
-          "When allocation tracing is enabled, the allocation stalls "      \
-          "larger than this threshold would be reported as warnings. "      \
-          "Time is in microseconds.")                                       \
-                                                                            \
   experimental(uintx, ShenandoahEvacAssist, 10,                             \
           "How many objects to evacuate on LRB assist path. "               \
           "Use zero to disable.")                                           \