Mercurial > hg > truffle
view src/share/vm/gc_implementation/g1/collectionSetChooser.cpp @ 3758:e2ce15aa3daf
Merge
author | never |
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date | Tue, 14 Jun 2011 15:20:55 -0700 |
parents | 371bbc844bf1 |
children | 20213c8a3c40 |
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/* * Copyright (c) 2001, 2010, 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 "gc_implementation/g1/collectionSetChooser.hpp" #include "gc_implementation/g1/g1CollectedHeap.inline.hpp" #include "gc_implementation/g1/g1CollectorPolicy.hpp" #include "memory/space.inline.hpp" CSetChooserCache::CSetChooserCache() { for (int i = 0; i < CacheLength; ++i) _cache[i] = NULL; clear(); } void CSetChooserCache::clear() { _occupancy = 0; _first = 0; for (int i = 0; i < CacheLength; ++i) { HeapRegion *hr = _cache[i]; if (hr != NULL) hr->set_sort_index(-1); _cache[i] = NULL; } } #ifndef PRODUCT bool CSetChooserCache::verify() { int index = _first; HeapRegion *prev = NULL; for (int i = 0; i < _occupancy; ++i) { guarantee(_cache[index] != NULL, "cache entry should not be empty"); HeapRegion *hr = _cache[index]; guarantee(!hr->is_young(), "should not be young!"); if (prev != NULL) { guarantee(prev->gc_efficiency() >= hr->gc_efficiency(), "cache should be correctly ordered"); } guarantee(hr->sort_index() == get_sort_index(index), "sort index should be correct"); index = trim_index(index + 1); prev = hr; } for (int i = 0; i < (CacheLength - _occupancy); ++i) { guarantee(_cache[index] == NULL, "cache entry should be empty"); index = trim_index(index + 1); } guarantee(index == _first, "we should have reached where we started from"); return true; } #endif // PRODUCT void CSetChooserCache::insert(HeapRegion *hr) { assert(!is_full(), "cache should not be empty"); hr->calc_gc_efficiency(); int empty_index; if (_occupancy == 0) { empty_index = _first; } else { empty_index = trim_index(_first + _occupancy); assert(_cache[empty_index] == NULL, "last slot should be empty"); int last_index = trim_index(empty_index - 1); HeapRegion *last = _cache[last_index]; assert(last != NULL,"as the cache is not empty, last should not be empty"); while (empty_index != _first && last->gc_efficiency() < hr->gc_efficiency()) { _cache[empty_index] = last; last->set_sort_index(get_sort_index(empty_index)); empty_index = last_index; last_index = trim_index(last_index - 1); last = _cache[last_index]; } } _cache[empty_index] = hr; hr->set_sort_index(get_sort_index(empty_index)); ++_occupancy; assert(verify(), "cache should be consistent"); } HeapRegion *CSetChooserCache::remove_first() { if (_occupancy > 0) { assert(_cache[_first] != NULL, "cache should have at least one region"); HeapRegion *ret = _cache[_first]; _cache[_first] = NULL; ret->set_sort_index(-1); --_occupancy; _first = trim_index(_first + 1); assert(verify(), "cache should be consistent"); return ret; } else { return NULL; } } // this is a bit expensive... but we expect that it should not be called // to often. void CSetChooserCache::remove(HeapRegion *hr) { assert(_occupancy > 0, "cache should not be empty"); assert(hr->sort_index() < -1, "should already be in the cache"); int index = get_index(hr->sort_index()); assert(_cache[index] == hr, "index should be correct"); int next_index = trim_index(index + 1); int last_index = trim_index(_first + _occupancy - 1); while (index != last_index) { assert(_cache[next_index] != NULL, "should not be null"); _cache[index] = _cache[next_index]; _cache[index]->set_sort_index(get_sort_index(index)); index = next_index; next_index = trim_index(next_index+1); } assert(index == last_index, "should have reached the last one"); _cache[index] = NULL; hr->set_sort_index(-1); --_occupancy; assert(verify(), "cache should be consistent"); } static inline int orderRegions(HeapRegion* hr1, HeapRegion* hr2) { if (hr1 == NULL) { if (hr2 == NULL) return 0; else return 1; } else if (hr2 == NULL) { return -1; } if (hr2->gc_efficiency() < hr1->gc_efficiency()) return -1; else if (hr1->gc_efficiency() < hr2->gc_efficiency()) return 1; else return 0; } static int orderRegions(HeapRegion** hr1p, HeapRegion** hr2p) { return orderRegions(*hr1p, *hr2p); } CollectionSetChooser::CollectionSetChooser() : // The line below is the worst bit of C++ hackery I've ever written // (Detlefs, 11/23). You should think of it as equivalent to // "_regions(100, true)": initialize the growable array and inform it // that it should allocate its elem array(s) on the C heap. // // The first argument, however, is actually a comma expression // (set_allocation_type(this, C_HEAP), 100). The purpose of the // set_allocation_type() call is to replace the default allocation // type for embedded objects STACK_OR_EMBEDDED with C_HEAP. It will // allow to pass the assert in GenericGrowableArray() which checks // that a growable array object must be on C heap if elements are. // // Note: containing object is allocated on C heap since it is CHeapObj. // _markedRegions((ResourceObj::set_allocation_type((address)&_markedRegions, ResourceObj::C_HEAP), 100), true), _curMarkedIndex(0), _numMarkedRegions(0), _unmarked_age_1_returned_as_new(false), _first_par_unreserved_idx(0) {} #ifndef PRODUCT bool CollectionSetChooser::verify() { int index = 0; guarantee(_curMarkedIndex <= _numMarkedRegions, "_curMarkedIndex should be within bounds"); while (index < _curMarkedIndex) { guarantee(_markedRegions.at(index++) == NULL, "all entries before _curMarkedIndex should be NULL"); } HeapRegion *prev = NULL; while (index < _numMarkedRegions) { HeapRegion *curr = _markedRegions.at(index++); if (curr != NULL) { int si = curr->sort_index(); guarantee(!curr->is_young(), "should not be young!"); guarantee(si > -1 && si == (index-1), "sort index invariant"); if (prev != NULL) { guarantee(orderRegions(prev, curr) != 1, "regions should be sorted"); } prev = curr; } } return _cache.verify(); } #endif bool CollectionSetChooser::addRegionToCache() { assert(!_cache.is_full(), "cache should not be full"); HeapRegion *hr = NULL; while (hr == NULL && _curMarkedIndex < _numMarkedRegions) { hr = _markedRegions.at(_curMarkedIndex++); } if (hr == NULL) return false; assert(!hr->is_young(), "should not be young!"); assert(hr->sort_index() == _curMarkedIndex-1, "sort_index invariant"); _markedRegions.at_put(hr->sort_index(), NULL); _cache.insert(hr); assert(!_cache.is_empty(), "cache should not be empty"); assert(verify(), "cache should be consistent"); return false; } void CollectionSetChooser::fillCache() { while (!_cache.is_full() && addRegionToCache()) { } } void CollectionSetChooser::sortMarkedHeapRegions() { guarantee(_cache.is_empty(), "cache should be empty"); // First trim any unused portion of the top in the parallel case. if (_first_par_unreserved_idx > 0) { if (G1PrintParCleanupStats) { gclog_or_tty->print(" Truncating _markedRegions from %d to %d.\n", _markedRegions.length(), _first_par_unreserved_idx); } assert(_first_par_unreserved_idx <= _markedRegions.length(), "Or we didn't reserved enough length"); _markedRegions.trunc_to(_first_par_unreserved_idx); } _markedRegions.sort(orderRegions); assert(_numMarkedRegions <= _markedRegions.length(), "Requirement"); assert(_numMarkedRegions == 0 || _markedRegions.at(_numMarkedRegions-1) != NULL, "Testing _numMarkedRegions"); assert(_numMarkedRegions == _markedRegions.length() || _markedRegions.at(_numMarkedRegions) == NULL, "Testing _numMarkedRegions"); if (G1PrintParCleanupStats) { gclog_or_tty->print_cr(" Sorted %d marked regions.", _numMarkedRegions); } for (int i = 0; i < _numMarkedRegions; i++) { assert(_markedRegions.at(i) != NULL, "Should be true by sorting!"); _markedRegions.at(i)->set_sort_index(i); } if (G1PrintRegionLivenessInfo) { G1PrintRegionLivenessInfoClosure cl(gclog_or_tty, "Post-Sorting"); for (int i = 0; i < _numMarkedRegions; ++i) { HeapRegion* r = _markedRegions.at(i); cl.doHeapRegion(r); } } assert(verify(), "should now be sorted"); } void CollectionSetChooser::addMarkedHeapRegion(HeapRegion* hr) { assert(!hr->isHumongous(), "Humongous regions shouldn't be added to the collection set"); assert(!hr->is_young(), "should not be young!"); _markedRegions.append(hr); _numMarkedRegions++; hr->calc_gc_efficiency(); } void CollectionSetChooser:: prepareForAddMarkedHeapRegionsPar(size_t n_regions, size_t chunkSize) { _first_par_unreserved_idx = 0; size_t max_waste = ParallelGCThreads * chunkSize; // it should be aligned with respect to chunkSize size_t aligned_n_regions = (n_regions + (chunkSize - 1)) / chunkSize * chunkSize; assert( aligned_n_regions % chunkSize == 0, "should be aligned" ); _markedRegions.at_put_grow((int)(aligned_n_regions + max_waste - 1), NULL); } jint CollectionSetChooser::getParMarkedHeapRegionChunk(jint n_regions) { jint res = Atomic::add(n_regions, &_first_par_unreserved_idx); assert(_markedRegions.length() > res + n_regions - 1, "Should already have been expanded"); return res - n_regions; } void CollectionSetChooser::setMarkedHeapRegion(jint index, HeapRegion* hr) { assert(_markedRegions.at(index) == NULL, "precondition"); assert(!hr->is_young(), "should not be young!"); _markedRegions.at_put(index, hr); hr->calc_gc_efficiency(); } void CollectionSetChooser::incNumMarkedHeapRegions(jint inc_by) { (void)Atomic::add(inc_by, &_numMarkedRegions); } void CollectionSetChooser::clearMarkedHeapRegions(){ for (int i = 0; i < _markedRegions.length(); i++) { HeapRegion* r = _markedRegions.at(i); if (r != NULL) r->set_sort_index(-1); } _markedRegions.clear(); _curMarkedIndex = 0; _numMarkedRegions = 0; _cache.clear(); }; void CollectionSetChooser::updateAfterFullCollection() { clearMarkedHeapRegions(); } void CollectionSetChooser::removeRegion(HeapRegion *hr) { int si = hr->sort_index(); assert(si == -1 || hr->is_marked(), "Sort index not valid."); if (si > -1) { assert(_markedRegions.at(si) == hr, "Sort index not valid." ); _markedRegions.at_put(si, NULL); } else if (si < -1) { assert(_cache.region_in_cache(hr), "should be in the cache"); _cache.remove(hr); assert(hr->sort_index() == -1, "sort index invariant"); } hr->set_sort_index(-1); } // if time_remaining < 0.0, then this method should try to return // a region, whether it fits within the remaining time or not HeapRegion* CollectionSetChooser::getNextMarkedRegion(double time_remaining, double avg_prediction) { G1CollectedHeap* g1h = G1CollectedHeap::heap(); G1CollectorPolicy* g1p = g1h->g1_policy(); fillCache(); if (_cache.is_empty()) { assert(_curMarkedIndex == _numMarkedRegions, "if cache is empty, list should also be empty"); return NULL; } HeapRegion *hr = _cache.get_first(); assert(hr != NULL, "if cache not empty, first entry should be non-null"); double predicted_time = g1h->predict_region_elapsed_time_ms(hr, false); if (g1p->adaptive_young_list_length()) { if (time_remaining - predicted_time < 0.0) { g1h->check_if_region_is_too_expensive(predicted_time); return NULL; } } else { if (predicted_time > 2.0 * avg_prediction) { return NULL; } } HeapRegion *hr2 = _cache.remove_first(); assert(hr == hr2, "cache contents should not have changed"); return hr; }