duke@435: /* xdono@1014: * Copyright 1999-2009 Sun Microsystems, Inc. All Rights Reserved. duke@435: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. duke@435: * duke@435: * This code is free software; you can redistribute it and/or modify it duke@435: * under the terms of the GNU General Public License version 2 only, as duke@435: * published by the Free Software Foundation. duke@435: * duke@435: * This code is distributed in the hope that it will be useful, but WITHOUT duke@435: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or duke@435: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License duke@435: * version 2 for more details (a copy is included in the LICENSE file that duke@435: * accompanied this code). duke@435: * duke@435: * You should have received a copy of the GNU General Public License version duke@435: * 2 along with this work; if not, write to the Free Software Foundation, duke@435: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. duke@435: * duke@435: * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, duke@435: * CA 95054 USA or visit www.sun.com if you need additional information or duke@435: * have any questions. duke@435: * duke@435: */ duke@435: duke@435: // Thread-Local Edens support duke@435: duke@435: # include "incls/_precompiled.incl" duke@435: # include "incls/_threadLocalAllocBuffer.cpp.incl" duke@435: duke@435: // static member initialization duke@435: unsigned ThreadLocalAllocBuffer::_target_refills = 0; duke@435: GlobalTLABStats* ThreadLocalAllocBuffer::_global_stats = NULL; duke@435: duke@435: void ThreadLocalAllocBuffer::clear_before_allocation() { duke@435: _slow_refill_waste += (unsigned)remaining(); duke@435: make_parsable(true); // also retire the TLAB duke@435: } duke@435: duke@435: void ThreadLocalAllocBuffer::accumulate_statistics_before_gc() { duke@435: global_stats()->initialize(); duke@435: duke@435: for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { duke@435: thread->tlab().accumulate_statistics(); duke@435: thread->tlab().initialize_statistics(); duke@435: } duke@435: duke@435: // Publish new stats if some allocation occurred. duke@435: if (global_stats()->allocation() != 0) { duke@435: global_stats()->publish(); duke@435: if (PrintTLAB) { duke@435: global_stats()->print(); duke@435: } duke@435: } duke@435: } duke@435: duke@435: void ThreadLocalAllocBuffer::accumulate_statistics() { duke@435: size_t capacity = Universe::heap()->tlab_capacity(myThread()) / HeapWordSize; duke@435: size_t unused = Universe::heap()->unsafe_max_tlab_alloc(myThread()) / HeapWordSize; duke@435: size_t used = capacity - unused; duke@435: duke@435: // Update allocation history if a reasonable amount of eden was allocated. duke@435: bool update_allocation_history = used > 0.5 * capacity; duke@435: duke@435: _gc_waste += (unsigned)remaining(); duke@435: duke@435: if (PrintTLAB && (_number_of_refills > 0 || Verbose)) { duke@435: print_stats("gc"); duke@435: } duke@435: duke@435: if (_number_of_refills > 0) { duke@435: duke@435: if (update_allocation_history) { duke@435: // Average the fraction of eden allocated in a tlab by this duke@435: // thread for use in the next resize operation. duke@435: // _gc_waste is not subtracted because it's included in duke@435: // "used". duke@435: size_t allocation = _number_of_refills * desired_size(); duke@435: double alloc_frac = allocation / (double) used; duke@435: _allocation_fraction.sample(alloc_frac); duke@435: } duke@435: global_stats()->update_allocating_threads(); duke@435: global_stats()->update_number_of_refills(_number_of_refills); duke@435: global_stats()->update_allocation(_number_of_refills * desired_size()); duke@435: global_stats()->update_gc_waste(_gc_waste); duke@435: global_stats()->update_slow_refill_waste(_slow_refill_waste); duke@435: global_stats()->update_fast_refill_waste(_fast_refill_waste); duke@435: duke@435: } else { duke@435: assert(_number_of_refills == 0 && _fast_refill_waste == 0 && duke@435: _slow_refill_waste == 0 && _gc_waste == 0, duke@435: "tlab stats == 0"); duke@435: } duke@435: global_stats()->update_slow_allocations(_slow_allocations); duke@435: } duke@435: duke@435: // Fills the current tlab with a dummy filler array to create duke@435: // an illusion of a contiguous Eden and optionally retires the tlab. duke@435: // Waste accounting should be done in caller as appropriate; see, duke@435: // for example, clear_before_allocation(). duke@435: void ThreadLocalAllocBuffer::make_parsable(bool retire) { duke@435: if (end() != NULL) { duke@435: invariants(); johnc@1600: CollectedHeap::fill_with_object(top(), hard_end(), retire); duke@435: duke@435: if (retire || ZeroTLAB) { // "Reset" the TLAB duke@435: set_start(NULL); duke@435: set_top(NULL); duke@435: set_pf_top(NULL); duke@435: set_end(NULL); duke@435: } duke@435: } duke@435: assert(!(retire || ZeroTLAB) || duke@435: (start() == NULL && end() == NULL && top() == NULL), duke@435: "TLAB must be reset"); duke@435: } duke@435: duke@435: void ThreadLocalAllocBuffer::resize_all_tlabs() { duke@435: for(JavaThread *thread = Threads::first(); thread; thread = thread->next()) { duke@435: thread->tlab().resize(); duke@435: } duke@435: } duke@435: duke@435: void ThreadLocalAllocBuffer::resize() { duke@435: duke@435: if (ResizeTLAB) { duke@435: // Compute the next tlab size using expected allocation amount duke@435: size_t alloc = (size_t)(_allocation_fraction.average() * duke@435: (Universe::heap()->tlab_capacity(myThread()) / HeapWordSize)); duke@435: size_t new_size = alloc / _target_refills; duke@435: duke@435: new_size = MIN2(MAX2(new_size, min_size()), max_size()); duke@435: duke@435: size_t aligned_new_size = align_object_size(new_size); duke@435: duke@435: if (PrintTLAB && Verbose) { duke@435: gclog_or_tty->print("TLAB new size: thread: " INTPTR_FORMAT " [id: %2d]" duke@435: " refills %d alloc: %8.6f desired_size: " SIZE_FORMAT " -> " SIZE_FORMAT "\n", duke@435: myThread(), myThread()->osthread()->thread_id(), duke@435: _target_refills, _allocation_fraction.average(), desired_size(), aligned_new_size); duke@435: } duke@435: set_desired_size(aligned_new_size); duke@435: duke@435: set_refill_waste_limit(initial_refill_waste_limit()); duke@435: } duke@435: } duke@435: duke@435: void ThreadLocalAllocBuffer::initialize_statistics() { duke@435: _number_of_refills = 0; duke@435: _fast_refill_waste = 0; duke@435: _slow_refill_waste = 0; duke@435: _gc_waste = 0; duke@435: _slow_allocations = 0; duke@435: } duke@435: duke@435: void ThreadLocalAllocBuffer::fill(HeapWord* start, duke@435: HeapWord* top, duke@435: size_t new_size) { duke@435: _number_of_refills++; duke@435: if (PrintTLAB && Verbose) { duke@435: print_stats("fill"); duke@435: } duke@435: assert(top <= start + new_size - alignment_reserve(), "size too small"); duke@435: initialize(start, top, start + new_size - alignment_reserve()); duke@435: duke@435: // Reset amount of internal fragmentation duke@435: set_refill_waste_limit(initial_refill_waste_limit()); duke@435: } duke@435: duke@435: void ThreadLocalAllocBuffer::initialize(HeapWord* start, duke@435: HeapWord* top, duke@435: HeapWord* end) { duke@435: set_start(start); duke@435: set_top(top); duke@435: set_pf_top(top); duke@435: set_end(end); duke@435: invariants(); duke@435: } duke@435: duke@435: void ThreadLocalAllocBuffer::initialize() { duke@435: initialize(NULL, // start duke@435: NULL, // top duke@435: NULL); // end duke@435: duke@435: set_desired_size(initial_desired_size()); duke@435: duke@435: // Following check is needed because at startup the main (primordial) duke@435: // thread is initialized before the heap is. The initialization for duke@435: // this thread is redone in startup_initialization below. duke@435: if (Universe::heap() != NULL) { duke@435: size_t capacity = Universe::heap()->tlab_capacity(myThread()) / HeapWordSize; duke@435: double alloc_frac = desired_size() * target_refills() / (double) capacity; duke@435: _allocation_fraction.sample(alloc_frac); duke@435: } duke@435: duke@435: set_refill_waste_limit(initial_refill_waste_limit()); duke@435: duke@435: initialize_statistics(); duke@435: } duke@435: duke@435: void ThreadLocalAllocBuffer::startup_initialization() { duke@435: duke@435: // Assuming each thread's active tlab is, on average, duke@435: // 1/2 full at a GC duke@435: _target_refills = 100 / (2 * TLABWasteTargetPercent); duke@435: _target_refills = MAX2(_target_refills, (unsigned)1U); duke@435: duke@435: _global_stats = new GlobalTLABStats(); duke@435: duke@435: // During jvm startup, the main (primordial) thread is initialized duke@435: // before the heap is initialized. So reinitialize it now. duke@435: guarantee(Thread::current()->is_Java_thread(), "tlab initialization thread not Java thread"); duke@435: Thread::current()->tlab().initialize(); duke@435: duke@435: if (PrintTLAB && Verbose) { duke@435: gclog_or_tty->print("TLAB min: " SIZE_FORMAT " initial: " SIZE_FORMAT " max: " SIZE_FORMAT "\n", duke@435: min_size(), Thread::current()->tlab().initial_desired_size(), max_size()); duke@435: } duke@435: } duke@435: duke@435: size_t ThreadLocalAllocBuffer::initial_desired_size() { duke@435: size_t init_sz; duke@435: duke@435: if (TLABSize > 0) { duke@435: init_sz = MIN2(TLABSize / HeapWordSize, max_size()); duke@435: } else if (global_stats() == NULL) { duke@435: // Startup issue - main thread initialized before heap initialized. duke@435: init_sz = min_size(); duke@435: } else { duke@435: // Initial size is a function of the average number of allocating threads. duke@435: unsigned nof_threads = global_stats()->allocating_threads_avg(); duke@435: duke@435: init_sz = (Universe::heap()->tlab_capacity(myThread()) / HeapWordSize) / duke@435: (nof_threads * target_refills()); duke@435: init_sz = align_object_size(init_sz); duke@435: init_sz = MIN2(MAX2(init_sz, min_size()), max_size()); duke@435: } duke@435: return init_sz; duke@435: } duke@435: duke@435: const size_t ThreadLocalAllocBuffer::max_size() { duke@435: duke@435: // TLABs can't be bigger than we can fill with a int[Integer.MAX_VALUE]. duke@435: // This restriction could be removed by enabling filling with multiple arrays. duke@435: // If we compute that the reasonable way as duke@435: // header_size + ((sizeof(jint) * max_jint) / HeapWordSize) duke@435: // we'll overflow on the multiply, so we do the divide first. duke@435: // We actually lose a little by dividing first, duke@435: // but that just makes the TLAB somewhat smaller than the biggest array, duke@435: // which is fine, since we'll be able to fill that. duke@435: duke@435: size_t unaligned_max_size = typeArrayOopDesc::header_size(T_INT) + duke@435: sizeof(jint) * duke@435: ((juint) max_jint / (size_t) HeapWordSize); duke@435: return align_size_down(unaligned_max_size, MinObjAlignment); duke@435: } duke@435: duke@435: void ThreadLocalAllocBuffer::print_stats(const char* tag) { duke@435: Thread* thrd = myThread(); duke@435: size_t waste = _gc_waste + _slow_refill_waste + _fast_refill_waste; duke@435: size_t alloc = _number_of_refills * _desired_size; duke@435: double waste_percent = alloc == 0 ? 0.0 : duke@435: 100.0 * waste / alloc; duke@435: size_t tlab_used = Universe::heap()->tlab_capacity(thrd) - duke@435: Universe::heap()->unsafe_max_tlab_alloc(thrd); duke@435: gclog_or_tty->print("TLAB: %s thread: " INTPTR_FORMAT " [id: %2d]" duke@435: " desired_size: " SIZE_FORMAT "KB" duke@435: " slow allocs: %d refill waste: " SIZE_FORMAT "B" duke@435: " alloc:%8.5f %8.0fKB refills: %d waste %4.1f%% gc: %dB" duke@435: " slow: %dB fast: %dB\n", duke@435: tag, thrd, thrd->osthread()->thread_id(), duke@435: _desired_size / (K / HeapWordSize), duke@435: _slow_allocations, _refill_waste_limit * HeapWordSize, duke@435: _allocation_fraction.average(), duke@435: _allocation_fraction.average() * tlab_used / K, duke@435: _number_of_refills, waste_percent, duke@435: _gc_waste * HeapWordSize, duke@435: _slow_refill_waste * HeapWordSize, duke@435: _fast_refill_waste * HeapWordSize); duke@435: } duke@435: duke@435: void ThreadLocalAllocBuffer::verify() { duke@435: HeapWord* p = start(); duke@435: HeapWord* t = top(); duke@435: HeapWord* prev_p = NULL; duke@435: while (p < t) { duke@435: oop(p)->verify(); duke@435: prev_p = p; duke@435: p += oop(p)->size(); duke@435: } duke@435: guarantee(p == top(), "end of last object must match end of space"); duke@435: } duke@435: duke@435: Thread* ThreadLocalAllocBuffer::myThread() { duke@435: return (Thread*)(((char *)this) + duke@435: in_bytes(start_offset()) - duke@435: in_bytes(Thread::tlab_start_offset())); duke@435: } duke@435: duke@435: duke@435: GlobalTLABStats::GlobalTLABStats() : duke@435: _allocating_threads_avg(TLABAllocationWeight) { duke@435: duke@435: initialize(); duke@435: duke@435: _allocating_threads_avg.sample(1); // One allocating thread at startup duke@435: duke@435: if (UsePerfData) { duke@435: duke@435: EXCEPTION_MARK; duke@435: ResourceMark rm; duke@435: duke@435: char* cname = PerfDataManager::counter_name("tlab", "allocThreads"); duke@435: _perf_allocating_threads = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_None, CHECK); duke@435: duke@435: cname = PerfDataManager::counter_name("tlab", "fills"); duke@435: _perf_total_refills = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_None, CHECK); duke@435: duke@435: cname = PerfDataManager::counter_name("tlab", "maxFills"); duke@435: _perf_max_refills = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_None, CHECK); duke@435: duke@435: cname = PerfDataManager::counter_name("tlab", "alloc"); duke@435: _perf_allocation = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK); duke@435: duke@435: cname = PerfDataManager::counter_name("tlab", "gcWaste"); duke@435: _perf_gc_waste = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK); duke@435: duke@435: cname = PerfDataManager::counter_name("tlab", "maxGcWaste"); duke@435: _perf_max_gc_waste = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK); duke@435: duke@435: cname = PerfDataManager::counter_name("tlab", "slowWaste"); duke@435: _perf_slow_refill_waste = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK); duke@435: duke@435: cname = PerfDataManager::counter_name("tlab", "maxSlowWaste"); duke@435: _perf_max_slow_refill_waste = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK); duke@435: duke@435: cname = PerfDataManager::counter_name("tlab", "fastWaste"); duke@435: _perf_fast_refill_waste = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK); duke@435: duke@435: cname = PerfDataManager::counter_name("tlab", "maxFastWaste"); duke@435: _perf_max_fast_refill_waste = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_Bytes, CHECK); duke@435: duke@435: cname = PerfDataManager::counter_name("tlab", "slowAlloc"); duke@435: _perf_slow_allocations = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_None, CHECK); duke@435: duke@435: cname = PerfDataManager::counter_name("tlab", "maxSlowAlloc"); duke@435: _perf_max_slow_allocations = duke@435: PerfDataManager::create_variable(SUN_GC, cname, PerfData::U_None, CHECK); duke@435: } duke@435: } duke@435: duke@435: void GlobalTLABStats::initialize() { duke@435: // Clear counters summarizing info from all threads duke@435: _allocating_threads = 0; duke@435: _total_refills = 0; duke@435: _max_refills = 0; duke@435: _total_allocation = 0; duke@435: _total_gc_waste = 0; duke@435: _max_gc_waste = 0; duke@435: _total_slow_refill_waste = 0; duke@435: _max_slow_refill_waste = 0; duke@435: _total_fast_refill_waste = 0; duke@435: _max_fast_refill_waste = 0; duke@435: _total_slow_allocations = 0; duke@435: _max_slow_allocations = 0; duke@435: } duke@435: duke@435: void GlobalTLABStats::publish() { duke@435: _allocating_threads_avg.sample(_allocating_threads); duke@435: if (UsePerfData) { duke@435: _perf_allocating_threads ->set_value(_allocating_threads); duke@435: _perf_total_refills ->set_value(_total_refills); duke@435: _perf_max_refills ->set_value(_max_refills); duke@435: _perf_allocation ->set_value(_total_allocation); duke@435: _perf_gc_waste ->set_value(_total_gc_waste); duke@435: _perf_max_gc_waste ->set_value(_max_gc_waste); duke@435: _perf_slow_refill_waste ->set_value(_total_slow_refill_waste); duke@435: _perf_max_slow_refill_waste->set_value(_max_slow_refill_waste); duke@435: _perf_fast_refill_waste ->set_value(_total_fast_refill_waste); duke@435: _perf_max_fast_refill_waste->set_value(_max_fast_refill_waste); duke@435: _perf_slow_allocations ->set_value(_total_slow_allocations); duke@435: _perf_max_slow_allocations ->set_value(_max_slow_allocations); duke@435: } duke@435: } duke@435: duke@435: void GlobalTLABStats::print() { duke@435: size_t waste = _total_gc_waste + _total_slow_refill_waste + _total_fast_refill_waste; duke@435: double waste_percent = _total_allocation == 0 ? 0.0 : duke@435: 100.0 * waste / _total_allocation; duke@435: gclog_or_tty->print("TLAB totals: thrds: %d refills: %d max: %d" duke@435: " slow allocs: %d max %d waste: %4.1f%%" duke@435: " gc: " SIZE_FORMAT "B max: " SIZE_FORMAT "B" duke@435: " slow: " SIZE_FORMAT "B max: " SIZE_FORMAT "B" duke@435: " fast: " SIZE_FORMAT "B max: " SIZE_FORMAT "B\n", duke@435: _allocating_threads, duke@435: _total_refills, _max_refills, duke@435: _total_slow_allocations, _max_slow_allocations, duke@435: waste_percent, duke@435: _total_gc_waste * HeapWordSize, duke@435: _max_gc_waste * HeapWordSize, duke@435: _total_slow_refill_waste * HeapWordSize, duke@435: _max_slow_refill_waste * HeapWordSize, duke@435: _total_fast_refill_waste * HeapWordSize, duke@435: _max_fast_refill_waste * HeapWordSize); duke@435: }