8297958: NMT: Display peak values

Reviewed-by: jsjolen, sjohanss

src/hotspot/share/services/mallocSiteTable.hpp

@@ -46,8 +46,12 @@ class MallocSite : public AllocationSite {
 
   // Memory allocated from this code path
   size_t size()  const { return _c.size(); }
+  // Peak memory ever allocated from this code path
+  size_t peak_size()  const { return _c.peak_size(); }
   // The number of calls were made
   size_t count() const { return _c.count(); }
+
+  const MemoryCounter* counter() const { return &_c; }
 };
 
 // Malloc site hashtable entry

src/hotspot/share/services/mallocTracker.cpp

@@ -27,6 +27,7 @@
 #include "jvm_io.h"
 #include "logging/log.hpp"
 #include "runtime/arguments.hpp"
+#include "runtime/atomic.hpp"
 #include "runtime/os.hpp"
 #include "runtime/safefetch.hpp"
 #include "services/mallocHeader.inline.hpp"
@@ -42,34 +43,20 @@ size_t MallocMemorySummary::_limits_per_category[mt_number_of_types] = { 0 };
 size_t MallocMemorySummary::_total_limit = 0;
 
 #ifdef ASSERT
-void MemoryCounter::update_peak_count(size_t count) {
-  size_t peak_cnt = peak_count();
-  while (peak_cnt < count) {
-    size_t old_cnt = Atomic::cmpxchg(&_peak_count, peak_cnt, count, memory_order_relaxed);
-    if (old_cnt != peak_cnt) {
-      peak_cnt = old_cnt;
-    }
-  }
-}
-
-void MemoryCounter::update_peak_size(size_t sz) {
+void MemoryCounter::update_peak(size_t size, size_t cnt) {
   size_t peak_sz = peak_size();
-  while (peak_sz < sz) {
-    size_t old_sz = Atomic::cmpxchg(&_peak_size, peak_sz, sz, memory_order_relaxed);
-    if (old_sz != peak_sz) {
+  while (peak_sz < size) {
+    size_t old_sz = Atomic::cmpxchg(&_peak_size, peak_sz, size, memory_order_relaxed);
+    if (old_sz == peak_sz) {
+      // I won
+      _peak_count = cnt;
+      break;
+    } else {
       peak_sz = old_sz;
     }
   }
 }
-
-size_t MemoryCounter::peak_count() const {
-  return Atomic::load(&_peak_count);
-}
-
-size_t MemoryCounter::peak_size() const {
-  return Atomic::load(&_peak_size);
-}
-#endif
+#endif // ASSERT
 
 // Total malloc'd memory used by arenas
 size_t MallocMemorySnapshot::total_arena() const {

src/hotspot/share/services/mallocTracker.hpp

@@ -45,8 +45,13 @@ class MemoryCounter {
   volatile size_t   _count;
   volatile size_t   _size;
 
-  DEBUG_ONLY(volatile size_t   _peak_count;)
-  DEBUG_ONLY(volatile size_t   _peak_size; )
+#ifdef ASSERT
+  // Peak size and count. Note: Peak count is the count at the point
+  // peak size was reached, not the absolute highest peak count.
+  volatile size_t _peak_count;
+  volatile size_t _peak_size;
+  void update_peak(size_t size, size_t cnt);
+#endif // ASSERT
 
  public:
   MemoryCounter() : _count(0), _size(0) {
@@ -58,9 +63,8 @@ class MemoryCounter {
     size_t cnt = Atomic::add(&_count, size_t(1), memory_order_relaxed);
     if (sz > 0) {
       size_t sum = Atomic::add(&_size, sz, memory_order_relaxed);
-      DEBUG_ONLY(update_peak_size(sum);)
+      DEBUG_ONLY(update_peak(sum, cnt);)
     }
-    DEBUG_ONLY(update_peak_count(cnt);)
   }
 
   inline void deallocate(size_t sz) {
@@ -76,19 +80,20 @@ class MemoryCounter {
     if (sz != 0) {
       assert(sz >= 0 || size() >= size_t(-sz), "Must be");
       size_t sum = Atomic::add(&_size, size_t(sz), memory_order_relaxed);
-      DEBUG_ONLY(update_peak_size(sum);)
+      DEBUG_ONLY(update_peak(sum, _count);)
     }
   }
 
   inline size_t count() const { return Atomic::load(&_count); }
   inline size_t size()  const { return Atomic::load(&_size);  }
 
-#ifdef ASSERT
-  void update_peak_count(size_t cnt);
-  void update_peak_size(size_t sz);
-  size_t peak_count() const;
-  size_t peak_size()  const;
-#endif // ASSERT
+  inline size_t peak_count() const {
+    return DEBUG_ONLY(Atomic::load(&_peak_count)) NOT_DEBUG(0);
+  }
+
+  inline size_t peak_size() const {
+    return DEBUG_ONLY(Atomic::load(&_peak_size)) NOT_DEBUG(0);
+  }
 };
 
 /*
@@ -125,12 +130,14 @@ class MallocMemory {
   }
 
   inline size_t malloc_size()  const { return _malloc.size(); }
+  inline size_t malloc_peak_size()  const { return _malloc.peak_size(); }
   inline size_t malloc_count() const { return _malloc.count();}
   inline size_t arena_size()   const { return _arena.size();  }
+  inline size_t arena_peak_size()  const { return _arena.peak_size(); }
   inline size_t arena_count()  const { return _arena.count(); }
 
-  DEBUG_ONLY(inline const MemoryCounter& malloc_counter() const { return _malloc; })
-  DEBUG_ONLY(inline const MemoryCounter& arena_counter()  const { return _arena;  })
+  const MemoryCounter* malloc_counter() const { return &_malloc; }
+  const MemoryCounter* arena_counter()  const { return &_arena;  }
 };
 
 class MallocMemorySummary;

src/hotspot/share/services/memReporter.cpp

@@ -45,11 +45,14 @@ void MemReporterBase::print_total(size_t reserved, size_t committed) const {
     amount_in_current_scale(reserved), scale, amount_in_current_scale(committed), scale);
 }
 
-void MemReporterBase::print_malloc(size_t amount, size_t count, MEMFLAGS flag) const {
+void MemReporterBase::print_malloc(const MemoryCounter* c, MEMFLAGS flag) const {
   const char* scale = current_scale();
   outputStream* out = output();
   const char* alloc_type = (flag == mtThreadStack) ? "" : "malloc=";
 
+  const size_t amount = c->size();
+  const size_t count = c->count();
+
   if (flag != mtNone) {
     out->print("(%s" SIZE_FORMAT "%s type=%s", alloc_type,
       amount_in_current_scale(amount), scale, NMTUtil::flag_to_name(flag));
@@ -58,11 +61,21 @@ void MemReporterBase::print_malloc(size_t amount, size_t count, MEMFLAGS flag) c
       amount_in_current_scale(amount), scale);
   }
 
+  // blends out mtChunk count number
   if (count > 0) {
     out->print(" #" SIZE_FORMAT "", count);
   }
 
   out->print(")");
+
+  size_t pk_amount = c->peak_size();
+  if (pk_amount == amount) {
+    out->print_raw(" (at peak)");
+  } else if (pk_amount > amount) {
+    size_t pk_count = c->peak_count();
+    out->print(" (peak=" SIZE_FORMAT "%s #" SIZE_FORMAT ")",
+        amount_in_current_scale(pk_amount), scale, pk_count);
+  }
 }
 
 void MemReporterBase::print_virtual_memory(size_t reserved, size_t committed) const {
@@ -71,9 +84,9 @@ void MemReporterBase::print_virtual_memory(size_t reserved, size_t committed) co
     amount_in_current_scale(reserved), scale, amount_in_current_scale(committed), scale);
 }
 
-void MemReporterBase::print_malloc_line(size_t amount, size_t count) const {
+void MemReporterBase::print_malloc_line(const MemoryCounter* c) const {
   output()->print("%28s", " ");
-  print_malloc(amount, count);
+  print_malloc(c);
   output()->print_cr(" ");
 }
 
@@ -83,10 +96,26 @@ void MemReporterBase::print_virtual_memory_line(size_t reserved, size_t committe
   output()->print_cr(" ");
 }
 
-void MemReporterBase::print_arena_line(size_t amount, size_t count) const {
+void MemReporterBase::print_arena_line(const MemoryCounter* c) const {
   const char* scale = current_scale();
-  output()->print_cr("%27s (arena=" SIZE_FORMAT "%s #" SIZE_FORMAT ")", " ",
+  outputStream* out = output();
+
+  const size_t amount = c->size();
+  const size_t count = c->count();
+
+  out->print("%27s (arena=" SIZE_FORMAT "%s #" SIZE_FORMAT ")", "",
     amount_in_current_scale(amount), scale, count);
+
+  size_t pk_amount = c->peak_size();
+  if (pk_amount == amount) {
+    out->print_raw(" (at peak)");
+  } else if (pk_amount > amount) {
+    size_t pk_count = c->peak_count();
+    out->print(" (peak=" SIZE_FORMAT "%s #" SIZE_FORMAT ")",
+        amount_in_current_scale(pk_amount), scale, pk_count);
+  }
+
+  out->cr();
 }
 
 void MemReporterBase::print_virtual_memory_region(const char* type, address base, size_t size) const {
@@ -195,18 +224,18 @@ void MemSummaryReporter::report_summary_of_type(MEMFLAGS flag,
     }
 
      // report malloc'd memory
-    if (amount_in_current_scale(malloc_memory->malloc_size()) > 0) {
-      // We don't know how many arena chunks are in used, so don't report the count
-      size_t count = (flag == mtChunk) ? 0 : malloc_memory->malloc_count();
-      print_malloc_line(malloc_memory->malloc_size(), count);
+    if (amount_in_current_scale(malloc_memory->malloc_size()) > 0
+        DEBUG_ONLY(|| amount_in_current_scale(malloc_memory->malloc_peak_size()) > 0)) {
+      print_malloc_line(malloc_memory->malloc_counter());
     }
 
     if (amount_in_current_scale(virtual_memory->reserved()) > 0) {
       print_virtual_memory_line(virtual_memory->reserved(), virtual_memory->committed());
     }
 
-    if (amount_in_current_scale(malloc_memory->arena_size()) > 0) {
-      print_arena_line(malloc_memory->arena_size(), malloc_memory->arena_count());
+    if (amount_in_current_scale(malloc_memory->arena_size()) > 0
+        DEBUG_ONLY(|| amount_in_current_scale(malloc_memory->arena_peak_size()) > 0)) {
+      print_arena_line(malloc_memory->arena_counter());
     }
 
     if (flag == mtNMT &&
@@ -271,12 +300,9 @@ int MemDetailReporter::report_malloc_sites() {
   const MallocSite* malloc_site;
   int num_omitted = 0;
   while ((malloc_site = malloc_itr.next()) != NULL) {
-    // Don't report free sites; does not count toward omitted count.
-    if (malloc_site->size() == 0) {
-      continue;
-    }
-    // Don't report if site has allocated less than one unit of whatever our scale is
-    if (scale() > 1 && amount_in_current_scale(malloc_site->size()) == 0) {
+    // Don't report if site has never allocated less than one unit of whatever our scale is
+    if (scale() > 1 && amount_in_current_scale(malloc_site->size()) == 0
+                       DEBUG_ONLY(&& amount_in_current_scale(malloc_site->peak_size()) == 0)) {
       num_omitted ++;
       continue;
     }
@@ -286,7 +312,7 @@ int MemDetailReporter::report_malloc_sites() {
     MEMFLAGS flag = malloc_site->flag();
     assert(NMTUtil::flag_is_valid(flag) && flag != mtNone,
       "Must have a valid memory type");
-    print_malloc(malloc_site->size(), malloc_site->count(),flag);
+    print_malloc(malloc_site->counter(), flag);
     out->print_cr("\n");
   }
   return num_omitted;

src/hotspot/share/services/memReporter.hpp

@@ -80,12 +80,12 @@ class MemReporterBase : public StackObj {
 
   // Print summary total, malloc and virtual memory
   void print_total(size_t reserved, size_t committed) const;
-  void print_malloc(size_t amount, size_t count, MEMFLAGS flag = mtNone) const;
+  void print_malloc(const MemoryCounter* c, MEMFLAGS flag = mtNone) const;
   void print_virtual_memory(size_t reserved, size_t committed) const;
 
-  void print_malloc_line(size_t amount, size_t count) const;
+  void print_malloc_line(const MemoryCounter* c) const;
   void print_virtual_memory_line(size_t reserved, size_t committed) const;
-  void print_arena_line(size_t amount, size_t count) const;
+  void print_arena_line(const MemoryCounter* c) const;
 
   void print_virtual_memory_region(const char* type, address base, size_t size) const;
 };