zgu@3900: /*
zgu@7074:  * Copyright (c) 2012, 2014, Oracle and/or its affiliates. All rights reserved.
zgu@3900:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
zgu@3900:  *
zgu@3900:  * This code is free software; you can redistribute it and/or modify it
zgu@3900:  * under the terms of the GNU General Public License version 2 only, as
zgu@3900:  * published by the Free Software Foundation.
zgu@3900:  *
zgu@3900:  * This code is distributed in the hope that it will be useful, but WITHOUT
zgu@3900:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
zgu@3900:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
zgu@3900:  * version 2 for more details (a copy is included in the LICENSE file that
zgu@3900:  * accompanied this code).
zgu@3900:  *
zgu@3900:  * You should have received a copy of the GNU General Public License version
zgu@3900:  * 2 along with this work; if not, write to the Free Software Foundation,
zgu@3900:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
zgu@3900:  *
zgu@3900:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
zgu@3900:  * or visit www.oracle.com if you need additional information or have any
zgu@3900:  * questions.
zgu@3900:  *
zgu@3900:  */
zgu@3900: #include "precompiled.hpp"
zgu@3900: 
zgu@7074: #include "runtime/mutex.hpp"
zgu@7074: #include "services/memBaseline.hpp"
zgu@3900: #include "services/memReporter.hpp"
zgu@7074: #include "services/mallocTracker.inline.hpp"
zgu@3900: #include "services/memTracker.hpp"
jprovino@5188: #include "utilities/defaultStream.hpp"
zgu@3900: 
zgu@7074: #ifdef SOLARIS
zgu@7074:   volatile bool NMT_stack_walkable = false;
zgu@7074: #else
zgu@7074:   volatile bool NMT_stack_walkable = true;
zgu@7074: #endif
zgu@3900: 
zgu@7074: volatile NMT_TrackingLevel MemTracker::_tracking_level = NMT_unknown;
zgu@7074: NMT_TrackingLevel MemTracker::_cmdline_tracking_level = NMT_unknown;
zgu@7074: 
zgu@7074: NativeCallStack emptyStack(0, false);
zgu@7074: 
zgu@7074: MemBaseline MemTracker::_baseline;
zgu@7074: Mutex*      MemTracker::_query_lock = NULL;
zgu@7074: bool MemTracker::_is_nmt_env_valid = true;
zgu@7074: 
zgu@7074: 
zgu@7074: NMT_TrackingLevel MemTracker::init_tracking_level() {
zgu@7074:   NMT_TrackingLevel level = NMT_off;
zgu@7074:   char buf[64];
zgu@7074:   char nmt_option[64];
zgu@7074:   jio_snprintf(buf, sizeof(buf), "NMT_LEVEL_%d", os::current_process_id());
zgu@7074:   if (os::getenv(buf, nmt_option, sizeof(nmt_option))) {
zgu@7074:     if (strcmp(nmt_option, "summary") == 0) {
zgu@7074:       level = NMT_summary;
zgu@7074:     } else if (strcmp(nmt_option, "detail") == 0) {
zgu@7074: #if PLATFORM_NATIVE_STACK_WALKING_SUPPORTED
zgu@7074:       level = NMT_detail;
zgu@7074: #else
zgu@7074:       level = NMT_summary;
zgu@7074: #endif // PLATFORM_NATIVE_STACK_WALKING_SUPPORTED
zgu@7074:     } else if (strcmp(nmt_option, "off") != 0) {
zgu@7074:       // The option value is invalid
zgu@7074:       _is_nmt_env_valid = false;
zgu@3900:     }
zgu@7074: 
zgu@7074:     // Remove the environment variable to avoid leaking to child processes
zgu@7074:     os::unsetenv(buf);
zgu@3900:   }
zgu@7074: 
zgu@7074:   if (!MallocTracker::initialize(level) ||
zgu@7074:       !VirtualMemoryTracker::initialize(level)) {
zgu@7074:     level = NMT_off;
zgu@7074:   }
zgu@7074:   return level;
zgu@3900: }
zgu@3900: 
zgu@7074: void MemTracker::init() {
zgu@7074:   if (tracking_level() >= NMT_summary) {
zgu@3936:     _query_lock = new (std::nothrow) Mutex(Monitor::max_nonleaf, "NMT_queryLock");
zgu@7074:     // Already OOM. It is unlikely, but still have to handle it.
zgu@3936:     if (_query_lock == NULL) {
zgu@7074:       shutdown();
zgu@3900:     }
zgu@3900:   }
zgu@3900: }
zgu@3900: 
zgu@7074: bool MemTracker::check_launcher_nmt_support(const char* value) {
zgu@7074:   if (strcmp(value, "=detail") == 0) {
zgu@7074: #if !PLATFORM_NATIVE_STACK_WALKING_SUPPORTED
zgu@7074:       jio_fprintf(defaultStream::error_stream(),
zgu@7074:         "NMT detail is not supported on this platform.  Using NMT summary instead.\n");
zgu@7074:     if (MemTracker::tracking_level() != NMT_summary) {
zgu@7074:     return false;
zgu@7074:   }
zgu@7074: #else
zgu@7074:     if (MemTracker::tracking_level() != NMT_detail) {
zgu@7074:       return false;
zgu@7074:     }
zgu@7074: #endif
zgu@7074:   } else if (strcmp(value, "=summary") == 0) {
zgu@7074:     if (MemTracker::tracking_level() != NMT_summary) {
zgu@7074:       return false;
zgu@7074:     }
zgu@7074:   } else if (strcmp(value, "=off") == 0) {
zgu@7074:     if (MemTracker::tracking_level() != NMT_off) {
zgu@7074:       return false;
zgu@7074:     }
zgu@7074:   } else {
zgu@7074:     _is_nmt_env_valid = false;
zgu@3900:   }
zgu@3900: 
zgu@7074:   return true;
zgu@3900: }
zgu@3900: 
zgu@7074: bool MemTracker::verify_nmt_option() {
zgu@7074:   return _is_nmt_env_valid;
zgu@7074: }
zgu@7074: 
zgu@7074: void* MemTracker::malloc_base(void* memblock) {
zgu@7074:   return MallocTracker::get_base(memblock);
zgu@7074: }
zgu@7074: 
zgu@7074: void Tracker::record(address addr, size_t size) {
zgu@7074:   if (MemTracker::tracking_level() < NMT_summary) return;
zgu@7074:   switch(_type) {
zgu@7074:     case uncommit:
zgu@7074:       VirtualMemoryTracker::remove_uncommitted_region(addr, size);
zgu@7074:       break;
zgu@7074:     case release:
zgu@7074:       VirtualMemoryTracker::remove_released_region(addr, size);
zgu@7074:         break;
zgu@7074:     default:
zgu@7074:       ShouldNotReachHere();
zgu@3900:   }
zgu@3900: }
zgu@3900: 
zgu@7074: 
zgu@7074: // Shutdown can only be issued via JCmd, and NMT JCmd is serialized
zgu@7074: // by lock
zgu@7074: void MemTracker::shutdown() {
zgu@7074:   // We can only shutdown NMT to minimal tracking level if it is
zgu@7074:   // ever on.
zgu@7074:   if (tracking_level () > NMT_minimal) {
zgu@7074:     transition_to(NMT_minimal);
zgu@3900:   }
zgu@3900: }
zgu@3900: 
zgu@7074: bool MemTracker::transition_to(NMT_TrackingLevel level) {
zgu@7074:   NMT_TrackingLevel current_level = tracking_level();
zgu@3900: 
zgu@7074:   if (current_level == level) {
zgu@7074:     return true;
zgu@7074:   } else if (current_level > level) {
zgu@7074:     // Downgrade tracking level, we want to lower the tracking
zgu@7074:     // level first
zgu@7074:     _tracking_level = level;
zgu@7074:     // Make _tracking_level visible immediately.
zgu@7074:     OrderAccess::fence();
zgu@7074:     VirtualMemoryTracker::transition(current_level, level);
zgu@7074:     MallocTracker::transition(current_level, level);
zgu@7074: 
zgu@7074:     if (level == NMT_minimal) _baseline.reset();
zgu@3900:   } else {
zgu@7074:     VirtualMemoryTracker::transition(current_level, level);
zgu@7074:     MallocTracker::transition(current_level, level);
zgu@7074: 
zgu@7074:     _tracking_level = level;
zgu@7074:     // Make _tracking_level visible immediately.
zgu@7074:     OrderAccess::fence();
zgu@3900:   }
zgu@3900: 
zgu@7074:   return true;
zgu@3900: }
zgu@3900: 
zgu@7074: void MemTracker::final_report(outputStream* output) {
zgu@7074:   assert(output != NULL, "No output stream");
zgu@7074:   if (tracking_level() >= NMT_summary) {
zgu@7074:     MallocMemorySnapshot* malloc_memory_snapshot =
zgu@7074:       MallocMemorySummary::as_snapshot();
zgu@7074:     malloc_memory_snapshot->make_adjustment();
zgu@7074: 
zgu@7074:     VirtualMemorySnapshot* virtual_memory_snapshot =
zgu@7074:       VirtualMemorySummary::as_snapshot();
zgu@7074: 
zgu@7074:     MemSummaryReporter rptr(malloc_memory_snapshot,
zgu@7074:       virtual_memory_snapshot, output);
zgu@7074:     rptr.report();
zgu@7074:     // shutdown NMT, the data no longer accurate
zgu@7074:     shutdown();
zgu@3900:   }
zgu@3900: }
zgu@3900: 
zgu@7074: // This is a walker to gather malloc site hashtable statistics,
zgu@7074: // the result is used for tuning.
zgu@7074: class StatisticsWalker : public MallocSiteWalker {
zgu@7074:  private:
zgu@7074:   enum Threshold {
zgu@7074:     // aggregates statistics over this threshold into one
zgu@7074:     // line item.
zgu@7074:     report_threshold = 20
zgu@7074:   };
zgu@3900: 
zgu@7074:  private:
zgu@7074:   // Number of allocation sites that have all memory freed
zgu@7074:   int   _empty_entries;
zgu@7074:   // Total number of allocation sites, include empty sites
zgu@7074:   int   _total_entries;
zgu@7074:   // Number of captured call stack distribution
zgu@7074:   int   _stack_depth_distribution[NMT_TrackingStackDepth];
zgu@7074:   // Hash distribution
zgu@7074:   int   _hash_distribution[report_threshold];
zgu@7074:   // Number of hash buckets that have entries over the threshold
zgu@7074:   int   _bucket_over_threshold;
zgu@7074: 
zgu@7074:   // The hash bucket that walker is currently walking
zgu@7074:   int   _current_hash_bucket;
zgu@7074:   // The length of current hash bucket
zgu@7074:   int   _current_bucket_length;
zgu@7074:   // Number of hash buckets that are not empty
zgu@7074:   int   _used_buckets;
zgu@7074:   // Longest hash bucket length
zgu@7074:   int   _longest_bucket_length;
zgu@7074: 
zgu@7074:  public:
zgu@7074:   StatisticsWalker() : _empty_entries(0), _total_entries(0) {
zgu@7074:     int index = 0;
zgu@7074:     for (index = 0; index < NMT_TrackingStackDepth; index ++) {
zgu@7074:       _stack_depth_distribution[index] = 0;
zgu@7074:     }
zgu@7074:     for (index = 0; index < report_threshold; index ++) {
zgu@7074:       _hash_distribution[index] = 0;
zgu@7074:     }
zgu@7074:     _bucket_over_threshold = 0;
zgu@7074:     _longest_bucket_length = 0;
zgu@7074:     _current_hash_bucket = -1;
zgu@7074:     _current_bucket_length = 0;
zgu@7074:     _used_buckets = 0;
zgu@3900:   }
zgu@3900: 
zgu@7074:   virtual bool at(const MallocSite* e) {
zgu@7074:     if (e->size() == 0) _empty_entries ++;
zgu@7074:     _total_entries ++;
zgu@3900: 
zgu@7074:     // stack depth distrubution
zgu@7074:     int frames = e->call_stack()->frames();
zgu@7074:     _stack_depth_distribution[frames - 1] ++;
zgu@3900: 
zgu@7074:     // hash distribution
zgu@7074:     int hash_bucket = e->hash() % MallocSiteTable::hash_buckets();
zgu@7074:     if (_current_hash_bucket == -1) {
zgu@7074:       _current_hash_bucket = hash_bucket;
zgu@7074:       _current_bucket_length = 1;
zgu@7074:     } else if (_current_hash_bucket == hash_bucket) {
zgu@7074:       _current_bucket_length ++;
zgu@7074:     } else {
zgu@7074:       record_bucket_length(_current_bucket_length);
zgu@7074:       _current_hash_bucket = hash_bucket;
zgu@7074:       _current_bucket_length = 1;
zgu@3900:     }
zgu@7074:     return true;
zgu@3900:   }
zgu@3900: 
zgu@7074:   // walk completed
zgu@7074:   void completed() {
zgu@7074:     record_bucket_length(_current_bucket_length);
zgu@3900:   }
zgu@3900: 
zgu@7074:   void report_statistics(outputStream* out) {
zgu@7074:     int index;
zgu@7074:     out->print_cr("Malloc allocation site table:");
zgu@7074:     out->print_cr("\tTotal entries: %d", _total_entries);
zgu@7074:     out->print_cr("\tEmpty entries: %d (%2.2f%%)", _empty_entries, ((float)_empty_entries * 100) / _total_entries);
zgu@7074:     out->print_cr(" ");
zgu@7074:     out->print_cr("Hash distribution:");
zgu@7074:     if (_used_buckets < MallocSiteTable::hash_buckets()) {
zgu@7074:       out->print_cr("empty bucket: %d", (MallocSiteTable::hash_buckets() - _used_buckets));
zgu@7074:     }
zgu@7074:     for (index = 0; index < report_threshold; index ++) {
zgu@7074:       if (_hash_distribution[index] != 0) {
zgu@7074:         if (index == 0) {
zgu@7074:           out->print_cr("  %d    entry: %d", 1, _hash_distribution[0]);
zgu@7074:         } else if (index < 9) { // single digit
zgu@7074:           out->print_cr("  %d  entries: %d", (index + 1), _hash_distribution[index]);
zgu@7074:         } else {
zgu@7074:           out->print_cr(" %d entries: %d", (index + 1), _hash_distribution[index]);
zgu@7074:         }
zgu@3900:       }
zgu@3900:     }
zgu@7074:     if (_bucket_over_threshold > 0) {
zgu@7074:       out->print_cr(" >%d entries: %d", report_threshold,  _bucket_over_threshold);
zgu@7074:     }
zgu@7074:     out->print_cr("most entries: %d", _longest_bucket_length);
zgu@7074:     out->print_cr(" ");
zgu@7074:     out->print_cr("Call stack depth distribution:");
zgu@7074:     for (index = 0; index < NMT_TrackingStackDepth; index ++) {
zgu@7074:       if (_stack_depth_distribution[index] > 0) {
zgu@7074:         out->print_cr("\t%d: %d", index + 1, _stack_depth_distribution[index]);
zgu@3900:       }
zgu@3900:     }
zgu@3900:   }
zgu@3900: 
zgu@7074:  private:
zgu@7074:   void record_bucket_length(int length) {
zgu@7074:     _used_buckets ++;
zgu@7074:     if (length <= report_threshold) {
zgu@7074:       _hash_distribution[length - 1] ++;
zgu@7074:     } else {
zgu@7074:       _bucket_over_threshold ++;
zgu@3900:     }
zgu@7074:     _longest_bucket_length = MAX2(_longest_bucket_length, length);
zgu@3900:   }
zgu@7074: };
zgu@7074: 
zgu@7074: 
zgu@7074: void MemTracker::tuning_statistics(outputStream* out) {
zgu@7074:   // NMT statistics
zgu@7074:   StatisticsWalker walker;
zgu@7074:   MallocSiteTable::walk_malloc_site(&walker);
zgu@7074:   walker.completed();
zgu@7074: 
zgu@7074:   out->print_cr("Native Memory Tracking Statistics:");
zgu@7074:   out->print_cr("Malloc allocation site table size: %d", MallocSiteTable::hash_buckets());
zgu@7074:   out->print_cr("             Tracking stack depth: %d", NMT_TrackingStackDepth);
zgu@7074:   NOT_PRODUCT(out->print_cr("Peak concurrent access: %d", MallocSiteTable::access_peak_count());)
zgu@7074:   out->print_cr(" ");
zgu@7074:   walker.report_statistics(out);
zgu@3900: }
zgu@3900: