Mercurial > hg > truffle
view src/share/vm/services/memTracker.cpp @ 21863:f4822d122041 jdk8u45-b11
Merge
author | asaha |
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date | Sat, 07 Mar 2015 16:26:10 -0800 |
parents | 417e3b8d04c5 |
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/* * Copyright (c) 2012, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "runtime/mutex.hpp" #include "services/memBaseline.hpp" #include "services/memReporter.hpp" #include "services/mallocTracker.inline.hpp" #include "services/memTracker.hpp" #include "utilities/defaultStream.hpp" #ifdef SOLARIS volatile bool NMT_stack_walkable = false; #else volatile bool NMT_stack_walkable = true; #endif volatile NMT_TrackingLevel MemTracker::_tracking_level = NMT_unknown; NMT_TrackingLevel MemTracker::_cmdline_tracking_level = NMT_unknown; MemBaseline MemTracker::_baseline; Mutex* MemTracker::_query_lock = NULL; bool MemTracker::_is_nmt_env_valid = true; NMT_TrackingLevel MemTracker::init_tracking_level() { NMT_TrackingLevel level = NMT_off; char buf[64]; char nmt_option[64]; jio_snprintf(buf, sizeof(buf), "NMT_LEVEL_%d", os::current_process_id()); if (os::getenv(buf, nmt_option, sizeof(nmt_option))) { if (strcmp(nmt_option, "summary") == 0) { level = NMT_summary; } else if (strcmp(nmt_option, "detail") == 0) { #if PLATFORM_NATIVE_STACK_WALKING_SUPPORTED level = NMT_detail; #else level = NMT_summary; #endif // PLATFORM_NATIVE_STACK_WALKING_SUPPORTED } else if (strcmp(nmt_option, "off") != 0) { // The option value is invalid _is_nmt_env_valid = false; } // Remove the environment variable to avoid leaking to child processes os::unsetenv(buf); } // Construct NativeCallStack::EMPTY_STACK. It may get constructed twice, // but it is benign, the results are the same. ::new ((void*)&NativeCallStack::EMPTY_STACK) NativeCallStack(0, false); if (!MallocTracker::initialize(level) || !VirtualMemoryTracker::initialize(level)) { level = NMT_off; } return level; } void MemTracker::init() { NMT_TrackingLevel level = tracking_level(); if (level >= NMT_summary) { if (!VirtualMemoryTracker::late_initialize(level)) { shutdown(); return; } _query_lock = new (std::nothrow) Mutex(Monitor::max_nonleaf, "NMT_queryLock"); // Already OOM. It is unlikely, but still have to handle it. if (_query_lock == NULL) { shutdown(); } } } bool MemTracker::check_launcher_nmt_support(const char* value) { if (strcmp(value, "=detail") == 0) { #if !PLATFORM_NATIVE_STACK_WALKING_SUPPORTED jio_fprintf(defaultStream::error_stream(), "NMT detail is not supported on this platform. Using NMT summary instead.\n"); if (MemTracker::tracking_level() != NMT_summary) { return false; } #else if (MemTracker::tracking_level() != NMT_detail) { return false; } #endif } else if (strcmp(value, "=summary") == 0) { if (MemTracker::tracking_level() != NMT_summary) { return false; } } else if (strcmp(value, "=off") == 0) { if (MemTracker::tracking_level() != NMT_off) { return false; } } else { _is_nmt_env_valid = false; } return true; } bool MemTracker::verify_nmt_option() { return _is_nmt_env_valid; } void* MemTracker::malloc_base(void* memblock) { return MallocTracker::get_base(memblock); } void Tracker::record(address addr, size_t size) { if (MemTracker::tracking_level() < NMT_summary) return; switch(_type) { case uncommit: VirtualMemoryTracker::remove_uncommitted_region(addr, size); break; case release: VirtualMemoryTracker::remove_released_region(addr, size); break; default: ShouldNotReachHere(); } } // Shutdown can only be issued via JCmd, and NMT JCmd is serialized by lock void MemTracker::shutdown() { // We can only shutdown NMT to minimal tracking level if it is ever on. if (tracking_level () > NMT_minimal) { transition_to(NMT_minimal); } } bool MemTracker::transition_to(NMT_TrackingLevel level) { NMT_TrackingLevel current_level = tracking_level(); assert(level != NMT_off || current_level == NMT_off, "Cannot transition NMT to off"); if (current_level == level) { return true; } else if (current_level > level) { // Downgrade tracking level, we want to lower the tracking level first _tracking_level = level; // Make _tracking_level visible immediately. OrderAccess::fence(); VirtualMemoryTracker::transition(current_level, level); MallocTracker::transition(current_level, level); } else { // Upgrading tracking level is not supported and has never been supported. // Allocating and deallocating malloc tracking structures is not thread safe and // leads to inconsistencies unless a lot coarser locks are added. } return true; } void MemTracker::report(bool summary_only, outputStream* output) { assert(output != NULL, "No output stream"); MemBaseline baseline; if (baseline.baseline(summary_only)) { if (summary_only) { MemSummaryReporter rpt(baseline, output); rpt.report(); } else { MemDetailReporter rpt(baseline, output); rpt.report(); } } } // This is a walker to gather malloc site hashtable statistics, // the result is used for tuning. class StatisticsWalker : public MallocSiteWalker { private: enum Threshold { // aggregates statistics over this threshold into one // line item. report_threshold = 20 }; private: // Number of allocation sites that have all memory freed int _empty_entries; // Total number of allocation sites, include empty sites int _total_entries; // Number of captured call stack distribution int _stack_depth_distribution[NMT_TrackingStackDepth]; // Hash distribution int _hash_distribution[report_threshold]; // Number of hash buckets that have entries over the threshold int _bucket_over_threshold; // The hash bucket that walker is currently walking int _current_hash_bucket; // The length of current hash bucket int _current_bucket_length; // Number of hash buckets that are not empty int _used_buckets; // Longest hash bucket length int _longest_bucket_length; public: StatisticsWalker() : _empty_entries(0), _total_entries(0) { int index = 0; for (index = 0; index < NMT_TrackingStackDepth; index ++) { _stack_depth_distribution[index] = 0; } for (index = 0; index < report_threshold; index ++) { _hash_distribution[index] = 0; } _bucket_over_threshold = 0; _longest_bucket_length = 0; _current_hash_bucket = -1; _current_bucket_length = 0; _used_buckets = 0; } virtual bool at(const MallocSite* e) { if (e->size() == 0) _empty_entries ++; _total_entries ++; // stack depth distrubution int frames = e->call_stack()->frames(); _stack_depth_distribution[frames - 1] ++; // hash distribution int hash_bucket = e->hash() % MallocSiteTable::hash_buckets(); if (_current_hash_bucket == -1) { _current_hash_bucket = hash_bucket; _current_bucket_length = 1; } else if (_current_hash_bucket == hash_bucket) { _current_bucket_length ++; } else { record_bucket_length(_current_bucket_length); _current_hash_bucket = hash_bucket; _current_bucket_length = 1; } return true; } // walk completed void completed() { record_bucket_length(_current_bucket_length); } void report_statistics(outputStream* out) { int index; out->print_cr("Malloc allocation site table:"); out->print_cr("\tTotal entries: %d", _total_entries); out->print_cr("\tEmpty entries: %d (%2.2f%%)", _empty_entries, ((float)_empty_entries * 100) / _total_entries); out->print_cr(" "); out->print_cr("Hash distribution:"); if (_used_buckets < MallocSiteTable::hash_buckets()) { out->print_cr("empty bucket: %d", (MallocSiteTable::hash_buckets() - _used_buckets)); } for (index = 0; index < report_threshold; index ++) { if (_hash_distribution[index] != 0) { if (index == 0) { out->print_cr(" %d entry: %d", 1, _hash_distribution[0]); } else if (index < 9) { // single digit out->print_cr(" %d entries: %d", (index + 1), _hash_distribution[index]); } else { out->print_cr(" %d entries: %d", (index + 1), _hash_distribution[index]); } } } if (_bucket_over_threshold > 0) { out->print_cr(" >%d entries: %d", report_threshold, _bucket_over_threshold); } out->print_cr("most entries: %d", _longest_bucket_length); out->print_cr(" "); out->print_cr("Call stack depth distribution:"); for (index = 0; index < NMT_TrackingStackDepth; index ++) { if (_stack_depth_distribution[index] > 0) { out->print_cr("\t%d: %d", index + 1, _stack_depth_distribution[index]); } } } private: void record_bucket_length(int length) { _used_buckets ++; if (length <= report_threshold) { _hash_distribution[length - 1] ++; } else { _bucket_over_threshold ++; } _longest_bucket_length = MAX2(_longest_bucket_length, length); } }; void MemTracker::tuning_statistics(outputStream* out) { // NMT statistics StatisticsWalker walker; MallocSiteTable::walk_malloc_site(&walker); walker.completed(); out->print_cr("Native Memory Tracking Statistics:"); out->print_cr("Malloc allocation site table size: %d", MallocSiteTable::hash_buckets()); out->print_cr(" Tracking stack depth: %d", NMT_TrackingStackDepth); NOT_PRODUCT(out->print_cr("Peak concurrent access: %d", MallocSiteTable::access_peak_count());) out->print_cr(" "); walker.report_statistics(out); }