Tue, 26 Jan 2010 16:52:29 -0800
6920090: G1: Disable ReduceInitialCardMarks at least until 6920109 is fixed
Summary: G1 now answers "no" to the query can_elide_initializing_store_barrier() in the product build. A debug flag allows alternate behaviour in debug builds.
Reviewed-by: iveresov, tonyp
ysr@777 | 1 | /* |
xdono@1279 | 2 | * Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved. |
ysr@777 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
ysr@777 | 4 | * |
ysr@777 | 5 | * This code is free software; you can redistribute it and/or modify it |
ysr@777 | 6 | * under the terms of the GNU General Public License version 2 only, as |
ysr@777 | 7 | * published by the Free Software Foundation. |
ysr@777 | 8 | * |
ysr@777 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
ysr@777 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
ysr@777 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
ysr@777 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
ysr@777 | 13 | * accompanied this code). |
ysr@777 | 14 | * |
ysr@777 | 15 | * You should have received a copy of the GNU General Public License version |
ysr@777 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
ysr@777 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
ysr@777 | 18 | * |
ysr@777 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
ysr@777 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
ysr@777 | 21 | * have any questions. |
ysr@777 | 22 | * |
ysr@777 | 23 | */ |
ysr@777 | 24 | |
ysr@777 | 25 | # include "incls/_precompiled.incl" |
ysr@777 | 26 | # include "incls/_collectionSetChooser.cpp.incl" |
ysr@777 | 27 | |
ysr@777 | 28 | CSetChooserCache::CSetChooserCache() { |
ysr@777 | 29 | for (int i = 0; i < CacheLength; ++i) |
ysr@777 | 30 | _cache[i] = NULL; |
ysr@777 | 31 | clear(); |
ysr@777 | 32 | } |
ysr@777 | 33 | |
ysr@777 | 34 | void CSetChooserCache::clear() { |
ysr@777 | 35 | _occupancy = 0; |
ysr@777 | 36 | _first = 0; |
ysr@777 | 37 | for (int i = 0; i < CacheLength; ++i) { |
ysr@777 | 38 | HeapRegion *hr = _cache[i]; |
ysr@777 | 39 | if (hr != NULL) |
ysr@777 | 40 | hr->set_sort_index(-1); |
ysr@777 | 41 | _cache[i] = NULL; |
ysr@777 | 42 | } |
ysr@777 | 43 | } |
ysr@777 | 44 | |
ysr@777 | 45 | #ifndef PRODUCT |
ysr@777 | 46 | bool CSetChooserCache::verify() { |
ysr@777 | 47 | int index = _first; |
ysr@777 | 48 | HeapRegion *prev = NULL; |
ysr@777 | 49 | for (int i = 0; i < _occupancy; ++i) { |
ysr@777 | 50 | guarantee(_cache[index] != NULL, "cache entry should not be empty"); |
ysr@777 | 51 | HeapRegion *hr = _cache[index]; |
ysr@777 | 52 | guarantee(!hr->is_young(), "should not be young!"); |
ysr@777 | 53 | if (prev != NULL) { |
ysr@777 | 54 | guarantee(prev->gc_efficiency() >= hr->gc_efficiency(), |
ysr@777 | 55 | "cache should be correctly ordered"); |
ysr@777 | 56 | } |
ysr@777 | 57 | guarantee(hr->sort_index() == get_sort_index(index), |
ysr@777 | 58 | "sort index should be correct"); |
ysr@777 | 59 | index = trim_index(index + 1); |
ysr@777 | 60 | prev = hr; |
ysr@777 | 61 | } |
ysr@777 | 62 | |
ysr@777 | 63 | for (int i = 0; i < (CacheLength - _occupancy); ++i) { |
ysr@777 | 64 | guarantee(_cache[index] == NULL, "cache entry should be empty"); |
ysr@777 | 65 | index = trim_index(index + 1); |
ysr@777 | 66 | } |
ysr@777 | 67 | |
ysr@777 | 68 | guarantee(index == _first, "we should have reached where we started from"); |
ysr@777 | 69 | return true; |
ysr@777 | 70 | } |
ysr@777 | 71 | #endif // PRODUCT |
ysr@777 | 72 | |
ysr@777 | 73 | void CSetChooserCache::insert(HeapRegion *hr) { |
ysr@777 | 74 | assert(!is_full(), "cache should not be empty"); |
ysr@777 | 75 | hr->calc_gc_efficiency(); |
ysr@777 | 76 | |
ysr@777 | 77 | int empty_index; |
ysr@777 | 78 | if (_occupancy == 0) { |
ysr@777 | 79 | empty_index = _first; |
ysr@777 | 80 | } else { |
ysr@777 | 81 | empty_index = trim_index(_first + _occupancy); |
ysr@777 | 82 | assert(_cache[empty_index] == NULL, "last slot should be empty"); |
ysr@777 | 83 | int last_index = trim_index(empty_index - 1); |
ysr@777 | 84 | HeapRegion *last = _cache[last_index]; |
ysr@777 | 85 | assert(last != NULL,"as the cache is not empty, last should not be empty"); |
ysr@777 | 86 | while (empty_index != _first && |
ysr@777 | 87 | last->gc_efficiency() < hr->gc_efficiency()) { |
ysr@777 | 88 | _cache[empty_index] = last; |
ysr@777 | 89 | last->set_sort_index(get_sort_index(empty_index)); |
ysr@777 | 90 | empty_index = last_index; |
ysr@777 | 91 | last_index = trim_index(last_index - 1); |
ysr@777 | 92 | last = _cache[last_index]; |
ysr@777 | 93 | } |
ysr@777 | 94 | } |
ysr@777 | 95 | _cache[empty_index] = hr; |
ysr@777 | 96 | hr->set_sort_index(get_sort_index(empty_index)); |
ysr@777 | 97 | |
ysr@777 | 98 | ++_occupancy; |
ysr@777 | 99 | assert(verify(), "cache should be consistent"); |
ysr@777 | 100 | } |
ysr@777 | 101 | |
ysr@777 | 102 | HeapRegion *CSetChooserCache::remove_first() { |
ysr@777 | 103 | if (_occupancy > 0) { |
ysr@777 | 104 | assert(_cache[_first] != NULL, "cache should have at least one region"); |
ysr@777 | 105 | HeapRegion *ret = _cache[_first]; |
ysr@777 | 106 | _cache[_first] = NULL; |
ysr@777 | 107 | ret->set_sort_index(-1); |
ysr@777 | 108 | --_occupancy; |
ysr@777 | 109 | _first = trim_index(_first + 1); |
ysr@777 | 110 | assert(verify(), "cache should be consistent"); |
ysr@777 | 111 | return ret; |
ysr@777 | 112 | } else { |
ysr@777 | 113 | return NULL; |
ysr@777 | 114 | } |
ysr@777 | 115 | } |
ysr@777 | 116 | |
ysr@777 | 117 | // this is a bit expensive... but we expect that it should not be called |
ysr@777 | 118 | // to often. |
ysr@777 | 119 | void CSetChooserCache::remove(HeapRegion *hr) { |
ysr@777 | 120 | assert(_occupancy > 0, "cache should not be empty"); |
ysr@777 | 121 | assert(hr->sort_index() < -1, "should already be in the cache"); |
ysr@777 | 122 | int index = get_index(hr->sort_index()); |
ysr@777 | 123 | assert(_cache[index] == hr, "index should be correct"); |
ysr@777 | 124 | int next_index = trim_index(index + 1); |
ysr@777 | 125 | int last_index = trim_index(_first + _occupancy - 1); |
ysr@777 | 126 | while (index != last_index) { |
ysr@777 | 127 | assert(_cache[next_index] != NULL, "should not be null"); |
ysr@777 | 128 | _cache[index] = _cache[next_index]; |
ysr@777 | 129 | _cache[index]->set_sort_index(get_sort_index(index)); |
ysr@777 | 130 | |
ysr@777 | 131 | index = next_index; |
ysr@777 | 132 | next_index = trim_index(next_index+1); |
ysr@777 | 133 | } |
ysr@777 | 134 | assert(index == last_index, "should have reached the last one"); |
ysr@777 | 135 | _cache[index] = NULL; |
ysr@777 | 136 | hr->set_sort_index(-1); |
ysr@777 | 137 | --_occupancy; |
ysr@777 | 138 | assert(verify(), "cache should be consistent"); |
ysr@777 | 139 | } |
ysr@777 | 140 | |
ysr@777 | 141 | static inline int orderRegions(HeapRegion* hr1, HeapRegion* hr2) { |
ysr@777 | 142 | if (hr1 == NULL) { |
ysr@777 | 143 | if (hr2 == NULL) return 0; |
ysr@777 | 144 | else return 1; |
ysr@777 | 145 | } else if (hr2 == NULL) { |
ysr@777 | 146 | return -1; |
ysr@777 | 147 | } |
ysr@777 | 148 | if (hr2->gc_efficiency() < hr1->gc_efficiency()) return -1; |
ysr@777 | 149 | else if (hr1->gc_efficiency() < hr2->gc_efficiency()) return 1; |
ysr@777 | 150 | else return 0; |
ysr@777 | 151 | } |
ysr@777 | 152 | |
ysr@777 | 153 | static int orderRegions(HeapRegion** hr1p, HeapRegion** hr2p) { |
ysr@777 | 154 | return orderRegions(*hr1p, *hr2p); |
ysr@777 | 155 | } |
ysr@777 | 156 | |
ysr@777 | 157 | CollectionSetChooser::CollectionSetChooser() : |
ysr@777 | 158 | // The line below is the worst bit of C++ hackery I've ever written |
ysr@777 | 159 | // (Detlefs, 11/23). You should think of it as equivalent to |
ysr@777 | 160 | // "_regions(100, true)": initialize the growable array and inform it |
ysr@777 | 161 | // that it should allocate its elem array(s) on the C heap. The first |
ysr@777 | 162 | // argument, however, is actually a comma expression (new-expr, 100). |
ysr@777 | 163 | // The purpose of the new_expr is to inform the growable array that it |
ysr@777 | 164 | // is *already* allocated on the C heap: it uses the placement syntax to |
ysr@777 | 165 | // keep it from actually doing any allocation. |
ysr@777 | 166 | _markedRegions((ResourceObj::operator new (sizeof(GrowableArray<HeapRegion*>), |
ysr@777 | 167 | (void*)&_markedRegions, |
ysr@777 | 168 | ResourceObj::C_HEAP), |
ysr@777 | 169 | 100), |
ysr@777 | 170 | true), |
ysr@777 | 171 | _curMarkedIndex(0), |
ysr@777 | 172 | _numMarkedRegions(0), |
ysr@777 | 173 | _unmarked_age_1_returned_as_new(false), |
ysr@777 | 174 | _first_par_unreserved_idx(0) |
ysr@777 | 175 | {} |
ysr@777 | 176 | |
ysr@777 | 177 | |
ysr@777 | 178 | |
ysr@777 | 179 | #ifndef PRODUCT |
ysr@777 | 180 | bool CollectionSetChooser::verify() { |
ysr@777 | 181 | int index = 0; |
ysr@777 | 182 | guarantee(_curMarkedIndex <= _numMarkedRegions, |
ysr@777 | 183 | "_curMarkedIndex should be within bounds"); |
ysr@777 | 184 | while (index < _curMarkedIndex) { |
ysr@777 | 185 | guarantee(_markedRegions.at(index++) == NULL, |
ysr@777 | 186 | "all entries before _curMarkedIndex should be NULL"); |
ysr@777 | 187 | } |
ysr@777 | 188 | HeapRegion *prev = NULL; |
ysr@777 | 189 | while (index < _numMarkedRegions) { |
ysr@777 | 190 | HeapRegion *curr = _markedRegions.at(index++); |
ysr@777 | 191 | if (curr != NULL) { |
ysr@777 | 192 | int si = curr->sort_index(); |
ysr@777 | 193 | guarantee(!curr->is_young(), "should not be young!"); |
ysr@777 | 194 | guarantee(si > -1 && si == (index-1), "sort index invariant"); |
ysr@777 | 195 | if (prev != NULL) { |
ysr@777 | 196 | guarantee(orderRegions(prev, curr) != 1, "regions should be sorted"); |
ysr@777 | 197 | } |
ysr@777 | 198 | prev = curr; |
ysr@777 | 199 | } |
ysr@777 | 200 | } |
ysr@777 | 201 | return _cache.verify(); |
ysr@777 | 202 | } |
ysr@777 | 203 | #endif |
ysr@777 | 204 | |
ysr@777 | 205 | bool |
ysr@777 | 206 | CollectionSetChooser::addRegionToCache() { |
ysr@777 | 207 | assert(!_cache.is_full(), "cache should not be full"); |
ysr@777 | 208 | |
ysr@777 | 209 | HeapRegion *hr = NULL; |
ysr@777 | 210 | while (hr == NULL && _curMarkedIndex < _numMarkedRegions) { |
ysr@777 | 211 | hr = _markedRegions.at(_curMarkedIndex++); |
ysr@777 | 212 | } |
ysr@777 | 213 | if (hr == NULL) |
ysr@777 | 214 | return false; |
ysr@777 | 215 | assert(!hr->is_young(), "should not be young!"); |
ysr@777 | 216 | assert(hr->sort_index() == _curMarkedIndex-1, "sort_index invariant"); |
ysr@777 | 217 | _markedRegions.at_put(hr->sort_index(), NULL); |
ysr@777 | 218 | _cache.insert(hr); |
ysr@777 | 219 | assert(!_cache.is_empty(), "cache should not be empty"); |
ysr@777 | 220 | assert(verify(), "cache should be consistent"); |
ysr@777 | 221 | return false; |
ysr@777 | 222 | } |
ysr@777 | 223 | |
ysr@777 | 224 | void |
ysr@777 | 225 | CollectionSetChooser::fillCache() { |
ysr@777 | 226 | while (!_cache.is_full() && addRegionToCache()) { |
ysr@777 | 227 | } |
ysr@777 | 228 | } |
ysr@777 | 229 | |
ysr@777 | 230 | void |
ysr@777 | 231 | CollectionSetChooser::sortMarkedHeapRegions() { |
ysr@777 | 232 | guarantee(_cache.is_empty(), "cache should be empty"); |
ysr@777 | 233 | // First trim any unused portion of the top in the parallel case. |
ysr@777 | 234 | if (_first_par_unreserved_idx > 0) { |
ysr@777 | 235 | if (G1PrintParCleanupStats) { |
ysr@777 | 236 | gclog_or_tty->print(" Truncating _markedRegions from %d to %d.\n", |
ysr@777 | 237 | _markedRegions.length(), _first_par_unreserved_idx); |
ysr@777 | 238 | } |
ysr@777 | 239 | assert(_first_par_unreserved_idx <= _markedRegions.length(), |
ysr@777 | 240 | "Or we didn't reserved enough length"); |
ysr@777 | 241 | _markedRegions.trunc_to(_first_par_unreserved_idx); |
ysr@777 | 242 | } |
ysr@777 | 243 | _markedRegions.sort(orderRegions); |
ysr@777 | 244 | assert(_numMarkedRegions <= _markedRegions.length(), "Requirement"); |
ysr@777 | 245 | assert(_numMarkedRegions == 0 |
ysr@777 | 246 | || _markedRegions.at(_numMarkedRegions-1) != NULL, |
ysr@777 | 247 | "Testing _numMarkedRegions"); |
ysr@777 | 248 | assert(_numMarkedRegions == _markedRegions.length() |
ysr@777 | 249 | || _markedRegions.at(_numMarkedRegions) == NULL, |
ysr@777 | 250 | "Testing _numMarkedRegions"); |
ysr@777 | 251 | if (G1PrintParCleanupStats) { |
ysr@777 | 252 | gclog_or_tty->print_cr(" Sorted %d marked regions.", _numMarkedRegions); |
ysr@777 | 253 | } |
ysr@777 | 254 | for (int i = 0; i < _numMarkedRegions; i++) { |
ysr@777 | 255 | assert(_markedRegions.at(i) != NULL, "Should be true by sorting!"); |
ysr@777 | 256 | _markedRegions.at(i)->set_sort_index(i); |
ysr@777 | 257 | if (G1PrintRegionLivenessInfo > 0) { |
ysr@777 | 258 | if (i == 0) gclog_or_tty->print_cr("Sorted marked regions:"); |
ysr@777 | 259 | if (i < G1PrintRegionLivenessInfo || |
ysr@777 | 260 | (_numMarkedRegions-i) < G1PrintRegionLivenessInfo) { |
ysr@777 | 261 | HeapRegion* hr = _markedRegions.at(i); |
ysr@777 | 262 | size_t u = hr->used(); |
ysr@777 | 263 | gclog_or_tty->print_cr(" Region %d: %d used, %d max live, %5.2f%%.", |
ysr@777 | 264 | i, u, hr->max_live_bytes(), |
ysr@777 | 265 | 100.0*(float)hr->max_live_bytes()/(float)u); |
ysr@777 | 266 | } |
ysr@777 | 267 | } |
ysr@777 | 268 | } |
ysr@777 | 269 | if (G1PolicyVerbose > 1) |
ysr@777 | 270 | printSortedHeapRegions(); |
ysr@777 | 271 | assert(verify(), "should now be sorted"); |
ysr@777 | 272 | } |
ysr@777 | 273 | |
ysr@777 | 274 | void |
ysr@777 | 275 | printHeapRegion(HeapRegion *hr) { |
ysr@777 | 276 | if (hr->isHumongous()) |
ysr@777 | 277 | gclog_or_tty->print("H: "); |
ysr@777 | 278 | if (hr->in_collection_set()) |
ysr@777 | 279 | gclog_or_tty->print("CS: "); |
ysr@777 | 280 | gclog_or_tty->print_cr("Region " PTR_FORMAT " (%s%s) " |
ysr@777 | 281 | "[" PTR_FORMAT ", " PTR_FORMAT"] " |
ysr@777 | 282 | "Used: " SIZE_FORMAT "K, garbage: " SIZE_FORMAT "K.", |
ysr@777 | 283 | hr, hr->is_young() ? "Y " : " ", |
ysr@777 | 284 | hr->is_marked()? "M1" : "M0", |
ysr@777 | 285 | hr->bottom(), hr->end(), |
ysr@777 | 286 | hr->used()/K, hr->garbage_bytes()/K); |
ysr@777 | 287 | } |
ysr@777 | 288 | |
ysr@777 | 289 | void |
ysr@777 | 290 | CollectionSetChooser::addMarkedHeapRegion(HeapRegion* hr) { |
ysr@777 | 291 | assert(!hr->isHumongous(), |
ysr@777 | 292 | "Humongous regions shouldn't be added to the collection set"); |
ysr@777 | 293 | assert(!hr->is_young(), "should not be young!"); |
ysr@777 | 294 | _markedRegions.append(hr); |
ysr@777 | 295 | _numMarkedRegions++; |
ysr@777 | 296 | hr->calc_gc_efficiency(); |
ysr@777 | 297 | } |
ysr@777 | 298 | |
ysr@777 | 299 | void |
ysr@777 | 300 | CollectionSetChooser:: |
ysr@777 | 301 | prepareForAddMarkedHeapRegionsPar(size_t n_regions, size_t chunkSize) { |
ysr@777 | 302 | _first_par_unreserved_idx = 0; |
ysr@777 | 303 | size_t max_waste = ParallelGCThreads * chunkSize; |
ysr@777 | 304 | // it should be aligned with respect to chunkSize |
ysr@777 | 305 | size_t aligned_n_regions = |
ysr@777 | 306 | (n_regions + (chunkSize - 1)) / chunkSize * chunkSize; |
ysr@777 | 307 | assert( aligned_n_regions % chunkSize == 0, "should be aligned" ); |
ysr@777 | 308 | _markedRegions.at_put_grow((int)(aligned_n_regions + max_waste - 1), NULL); |
ysr@777 | 309 | } |
ysr@777 | 310 | |
ysr@777 | 311 | jint |
ysr@777 | 312 | CollectionSetChooser::getParMarkedHeapRegionChunk(jint n_regions) { |
ysr@777 | 313 | jint res = Atomic::add(n_regions, &_first_par_unreserved_idx); |
ysr@777 | 314 | assert(_markedRegions.length() > res + n_regions - 1, |
ysr@777 | 315 | "Should already have been expanded"); |
ysr@777 | 316 | return res - n_regions; |
ysr@777 | 317 | } |
ysr@777 | 318 | |
ysr@777 | 319 | void |
ysr@777 | 320 | CollectionSetChooser::setMarkedHeapRegion(jint index, HeapRegion* hr) { |
ysr@777 | 321 | assert(_markedRegions.at(index) == NULL, "precondition"); |
ysr@777 | 322 | assert(!hr->is_young(), "should not be young!"); |
ysr@777 | 323 | _markedRegions.at_put(index, hr); |
ysr@777 | 324 | hr->calc_gc_efficiency(); |
ysr@777 | 325 | } |
ysr@777 | 326 | |
ysr@777 | 327 | void |
ysr@777 | 328 | CollectionSetChooser::incNumMarkedHeapRegions(jint inc_by) { |
ysr@777 | 329 | (void)Atomic::add(inc_by, &_numMarkedRegions); |
ysr@777 | 330 | } |
ysr@777 | 331 | |
ysr@777 | 332 | void |
ysr@777 | 333 | CollectionSetChooser::clearMarkedHeapRegions(){ |
ysr@777 | 334 | for (int i = 0; i < _markedRegions.length(); i++) { |
ysr@777 | 335 | HeapRegion* r = _markedRegions.at(i); |
ysr@777 | 336 | if (r != NULL) r->set_sort_index(-1); |
ysr@777 | 337 | } |
ysr@777 | 338 | _markedRegions.clear(); |
ysr@777 | 339 | _curMarkedIndex = 0; |
ysr@777 | 340 | _numMarkedRegions = 0; |
ysr@777 | 341 | _cache.clear(); |
ysr@777 | 342 | }; |
ysr@777 | 343 | |
ysr@777 | 344 | void |
ysr@777 | 345 | CollectionSetChooser::updateAfterFullCollection() { |
ysr@777 | 346 | G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
ysr@777 | 347 | clearMarkedHeapRegions(); |
ysr@777 | 348 | } |
ysr@777 | 349 | |
ysr@777 | 350 | void |
ysr@777 | 351 | CollectionSetChooser::printSortedHeapRegions() { |
ysr@777 | 352 | gclog_or_tty->print_cr("Printing %d Heap Regions sorted by amount of known garbage", |
ysr@777 | 353 | _numMarkedRegions); |
johnc@1538 | 354 | |
johnc@1538 | 355 | DEBUG_ONLY(int marked_count = 0;) |
ysr@777 | 356 | for (int i = 0; i < _markedRegions.length(); i++) { |
johnc@1538 | 357 | HeapRegion* r = _markedRegions.at(i); |
johnc@1538 | 358 | if (r != NULL) { |
johnc@1538 | 359 | printHeapRegion(r); |
johnc@1538 | 360 | DEBUG_ONLY(marked_count++;) |
johnc@1538 | 361 | } |
ysr@777 | 362 | } |
johnc@1538 | 363 | assert(marked_count == _numMarkedRegions, "must be"); |
ysr@777 | 364 | gclog_or_tty->print_cr("Done sorted heap region print"); |
ysr@777 | 365 | } |
ysr@777 | 366 | |
ysr@777 | 367 | void CollectionSetChooser::removeRegion(HeapRegion *hr) { |
ysr@777 | 368 | int si = hr->sort_index(); |
ysr@777 | 369 | assert(si == -1 || hr->is_marked(), "Sort index not valid."); |
ysr@777 | 370 | if (si > -1) { |
ysr@777 | 371 | assert(_markedRegions.at(si) == hr, "Sort index not valid." ); |
ysr@777 | 372 | _markedRegions.at_put(si, NULL); |
ysr@777 | 373 | } else if (si < -1) { |
ysr@777 | 374 | assert(_cache.region_in_cache(hr), "should be in the cache"); |
ysr@777 | 375 | _cache.remove(hr); |
ysr@777 | 376 | assert(hr->sort_index() == -1, "sort index invariant"); |
ysr@777 | 377 | } |
ysr@777 | 378 | hr->set_sort_index(-1); |
ysr@777 | 379 | } |
ysr@777 | 380 | |
ysr@777 | 381 | // if time_remaining < 0.0, then this method should try to return |
ysr@777 | 382 | // a region, whether it fits within the remaining time or not |
ysr@777 | 383 | HeapRegion* |
ysr@777 | 384 | CollectionSetChooser::getNextMarkedRegion(double time_remaining, |
ysr@777 | 385 | double avg_prediction) { |
ysr@777 | 386 | G1CollectedHeap* g1h = G1CollectedHeap::heap(); |
ysr@777 | 387 | G1CollectorPolicy* g1p = g1h->g1_policy(); |
ysr@777 | 388 | fillCache(); |
ysr@777 | 389 | if (_cache.is_empty()) { |
ysr@777 | 390 | assert(_curMarkedIndex == _numMarkedRegions, |
ysr@777 | 391 | "if cache is empty, list should also be empty"); |
ysr@777 | 392 | return NULL; |
ysr@777 | 393 | } |
ysr@777 | 394 | |
ysr@777 | 395 | HeapRegion *hr = _cache.get_first(); |
ysr@777 | 396 | assert(hr != NULL, "if cache not empty, first entry should be non-null"); |
ysr@777 | 397 | double predicted_time = g1h->predict_region_elapsed_time_ms(hr, false); |
ysr@777 | 398 | |
ysr@777 | 399 | if (g1p->adaptive_young_list_length()) { |
ysr@777 | 400 | if (time_remaining - predicted_time < 0.0) { |
ysr@777 | 401 | g1h->check_if_region_is_too_expensive(predicted_time); |
ysr@777 | 402 | return NULL; |
ysr@777 | 403 | } |
ysr@777 | 404 | } else { |
ysr@777 | 405 | if (predicted_time > 2.0 * avg_prediction) { |
ysr@777 | 406 | return NULL; |
ysr@777 | 407 | } |
ysr@777 | 408 | } |
ysr@777 | 409 | |
ysr@777 | 410 | HeapRegion *hr2 = _cache.remove_first(); |
ysr@777 | 411 | assert(hr == hr2, "cache contents should not have changed"); |
ysr@777 | 412 | |
ysr@777 | 413 | return hr; |
ysr@777 | 414 | } |