0
|
1 /*
|
|
2 * Copyright 2003-2006 Sun Microsystems, Inc. All Rights Reserved.
|
|
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
|
|
4 *
|
|
5 * This code is free software; you can redistribute it and/or modify it
|
|
6 * under the terms of the GNU General Public License version 2 only, as
|
|
7 * published by the Free Software Foundation.
|
|
8 *
|
|
9 * This code is distributed in the hope that it will be useful, but WITHOUT
|
|
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
|
12 * version 2 for more details (a copy is included in the LICENSE file that
|
|
13 * accompanied this code).
|
|
14 *
|
|
15 * You should have received a copy of the GNU General Public License version
|
|
16 * 2 along with this work; if not, write to the Free Software Foundation,
|
|
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
18 *
|
|
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
|
|
20 * CA 95054 USA or visit www.sun.com if you need additional information or
|
|
21 * have any questions.
|
|
22 *
|
|
23 */
|
|
24
|
|
25 # include "incls/_precompiled.incl"
|
|
26 # include "incls/_asPSYoungGen.cpp.incl"
|
|
27
|
|
28 ASPSYoungGen::ASPSYoungGen(size_t init_byte_size,
|
|
29 size_t minimum_byte_size,
|
|
30 size_t byte_size_limit) :
|
|
31 PSYoungGen(init_byte_size, minimum_byte_size, byte_size_limit),
|
|
32 _gen_size_limit(byte_size_limit) {
|
|
33 }
|
|
34
|
|
35
|
|
36 ASPSYoungGen::ASPSYoungGen(PSVirtualSpace* vs,
|
|
37 size_t init_byte_size,
|
|
38 size_t minimum_byte_size,
|
|
39 size_t byte_size_limit) :
|
|
40 //PSYoungGen(init_byte_size, minimum_byte_size, byte_size_limit),
|
|
41 PSYoungGen(vs->committed_size(), minimum_byte_size, byte_size_limit),
|
|
42 _gen_size_limit(byte_size_limit) {
|
|
43
|
|
44 assert(vs->committed_size() == init_byte_size, "Cannot replace with");
|
|
45
|
|
46 _virtual_space = vs;
|
|
47 }
|
|
48
|
|
49 void ASPSYoungGen::initialize_virtual_space(ReservedSpace rs,
|
|
50 size_t alignment) {
|
|
51 assert(_init_gen_size != 0, "Should have a finite size");
|
|
52 _virtual_space = new PSVirtualSpaceHighToLow(rs, alignment);
|
|
53 if (!_virtual_space->expand_by(_init_gen_size)) {
|
|
54 vm_exit_during_initialization("Could not reserve enough space for "
|
|
55 "object heap");
|
|
56 }
|
|
57 }
|
|
58
|
|
59 void ASPSYoungGen::initialize(ReservedSpace rs, size_t alignment) {
|
|
60 initialize_virtual_space(rs, alignment);
|
|
61 initialize_work();
|
|
62 }
|
|
63
|
|
64 size_t ASPSYoungGen::available_for_expansion() {
|
|
65
|
|
66 size_t current_committed_size = virtual_space()->committed_size();
|
|
67 assert((gen_size_limit() >= current_committed_size),
|
|
68 "generation size limit is wrong");
|
|
69 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
|
|
70 size_t result = gen_size_limit() - current_committed_size;
|
|
71 size_t result_aligned = align_size_down(result, heap->young_gen_alignment());
|
|
72 return result_aligned;
|
|
73 }
|
|
74
|
|
75 // Return the number of bytes the young gen is willing give up.
|
|
76 //
|
|
77 // Future implementations could check the survivors and if to_space is in the
|
|
78 // right place (below from_space), take a chunk from to_space.
|
|
79 size_t ASPSYoungGen::available_for_contraction() {
|
|
80
|
|
81 size_t uncommitted_bytes = virtual_space()->uncommitted_size();
|
|
82 if (uncommitted_bytes != 0) {
|
|
83 return uncommitted_bytes;
|
|
84 }
|
|
85
|
|
86 if (eden_space()->is_empty()) {
|
|
87 // Respect the minimum size for eden and for the young gen as a whole.
|
|
88 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
|
|
89 const size_t eden_alignment = heap->intra_generation_alignment();
|
|
90 const size_t gen_alignment = heap->young_gen_alignment();
|
|
91
|
|
92 assert(eden_space()->capacity_in_bytes() >= eden_alignment,
|
|
93 "Alignment is wrong");
|
|
94 size_t eden_avail = eden_space()->capacity_in_bytes() - eden_alignment;
|
|
95 eden_avail = align_size_down(eden_avail, gen_alignment);
|
|
96
|
|
97 assert(virtual_space()->committed_size() >= min_gen_size(),
|
|
98 "minimum gen size is wrong");
|
|
99 size_t gen_avail = virtual_space()->committed_size() - min_gen_size();
|
|
100 assert(virtual_space()->is_aligned(gen_avail), "not aligned");
|
|
101
|
|
102 const size_t max_contraction = MIN2(eden_avail, gen_avail);
|
|
103 // See comment for ASPSOldGen::available_for_contraction()
|
|
104 // for reasons the "increment" fraction is used.
|
|
105 PSAdaptiveSizePolicy* policy = heap->size_policy();
|
|
106 size_t result = policy->eden_increment_aligned_down(max_contraction);
|
|
107 size_t result_aligned = align_size_down(result, gen_alignment);
|
|
108 if (PrintAdaptiveSizePolicy && Verbose) {
|
|
109 gclog_or_tty->print_cr("ASPSYoungGen::available_for_contraction: %d K",
|
|
110 result_aligned/K);
|
|
111 gclog_or_tty->print_cr(" max_contraction %d K", max_contraction/K);
|
|
112 gclog_or_tty->print_cr(" eden_avail %d K", eden_avail/K);
|
|
113 gclog_or_tty->print_cr(" gen_avail %d K", gen_avail/K);
|
|
114 }
|
|
115 return result_aligned;
|
|
116
|
|
117 }
|
|
118
|
|
119 return 0;
|
|
120 }
|
|
121
|
|
122 // The current implementation only considers to the end of eden.
|
|
123 // If to_space is below from_space, to_space is not considered.
|
|
124 // to_space can be.
|
|
125 size_t ASPSYoungGen::available_to_live() {
|
|
126 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
|
|
127 const size_t alignment = heap->intra_generation_alignment();
|
|
128
|
|
129 // Include any space that is committed but is not in eden.
|
|
130 size_t available = pointer_delta(eden_space()->bottom(),
|
|
131 virtual_space()->low(),
|
|
132 sizeof(char));
|
|
133
|
|
134 const size_t eden_capacity = eden_space()->capacity_in_bytes();
|
|
135 if (eden_space()->is_empty() && eden_capacity > alignment) {
|
|
136 available += eden_capacity - alignment;
|
|
137 }
|
|
138 return available;
|
|
139 }
|
|
140
|
|
141 // Similar to PSYoungGen::resize_generation() but
|
|
142 // allows sum of eden_size and 2 * survivor_size to exceed _max_gen_size
|
|
143 // expands at the low end of the virtual space
|
|
144 // moves the boundary between the generations in order to expand
|
|
145 // some additional diagnostics
|
|
146 // If no additional changes are required, this can be deleted
|
|
147 // and the changes factored back into PSYoungGen::resize_generation().
|
|
148 bool ASPSYoungGen::resize_generation(size_t eden_size, size_t survivor_size) {
|
|
149 const size_t alignment = virtual_space()->alignment();
|
|
150 size_t orig_size = virtual_space()->committed_size();
|
|
151 bool size_changed = false;
|
|
152
|
|
153 // There used to be a guarantee here that
|
|
154 // (eden_size + 2*survivor_size) <= _max_gen_size
|
|
155 // This requirement is enforced by the calculation of desired_size
|
|
156 // below. It may not be true on entry since the size of the
|
|
157 // eden_size is no bounded by the generation size.
|
|
158
|
|
159 assert(max_size() == reserved().byte_size(), "max gen size problem?");
|
|
160 assert(min_gen_size() <= orig_size && orig_size <= max_size(),
|
|
161 "just checking");
|
|
162
|
|
163 // Adjust new generation size
|
|
164 const size_t eden_plus_survivors =
|
|
165 align_size_up(eden_size + 2 * survivor_size, alignment);
|
|
166 size_t desired_size = MAX2(MIN2(eden_plus_survivors, gen_size_limit()),
|
|
167 min_gen_size());
|
|
168 assert(desired_size <= gen_size_limit(), "just checking");
|
|
169
|
|
170 if (desired_size > orig_size) {
|
|
171 // Grow the generation
|
|
172 size_t change = desired_size - orig_size;
|
|
173 if (!virtual_space()->expand_by(change)) {
|
|
174 return false;
|
|
175 }
|
|
176 size_changed = true;
|
|
177 } else if (desired_size < orig_size) {
|
|
178 size_t desired_change = orig_size - desired_size;
|
|
179
|
|
180 // How much is available for shrinking.
|
|
181 size_t available_bytes = limit_gen_shrink(desired_change);
|
|
182 size_t change = MIN2(desired_change, available_bytes);
|
|
183 virtual_space()->shrink_by(change);
|
|
184 size_changed = true;
|
|
185 } else {
|
|
186 if (Verbose && PrintGC) {
|
|
187 if (orig_size == gen_size_limit()) {
|
|
188 gclog_or_tty->print_cr("ASPSYoung generation size at maximum: "
|
|
189 SIZE_FORMAT "K", orig_size/K);
|
|
190 } else if (orig_size == min_gen_size()) {
|
|
191 gclog_or_tty->print_cr("ASPSYoung generation size at minium: "
|
|
192 SIZE_FORMAT "K", orig_size/K);
|
|
193 }
|
|
194 }
|
|
195 }
|
|
196
|
|
197 if (size_changed) {
|
|
198 reset_after_change();
|
|
199 if (Verbose && PrintGC) {
|
|
200 size_t current_size = virtual_space()->committed_size();
|
|
201 gclog_or_tty->print_cr("ASPSYoung generation size changed: "
|
|
202 SIZE_FORMAT "K->" SIZE_FORMAT "K",
|
|
203 orig_size/K, current_size/K);
|
|
204 }
|
|
205 }
|
|
206
|
|
207 guarantee(eden_plus_survivors <= virtual_space()->committed_size() ||
|
|
208 virtual_space()->committed_size() == max_size(), "Sanity");
|
|
209
|
|
210 return true;
|
|
211 }
|
|
212
|
|
213 // Similar to PSYoungGen::resize_spaces() but
|
|
214 // eden always starts at the low end of the committed virtual space
|
|
215 // current implementation does not allow holes between the spaces
|
|
216 // _young_generation_boundary has to be reset because it changes.
|
|
217 // so additional verification
|
|
218 void ASPSYoungGen::resize_spaces(size_t requested_eden_size,
|
|
219 size_t requested_survivor_size) {
|
|
220 assert(requested_eden_size > 0 && requested_survivor_size > 0,
|
|
221 "just checking");
|
|
222
|
|
223 space_invariants();
|
|
224
|
|
225 // We require eden and to space to be empty
|
|
226 if ((!eden_space()->is_empty()) || (!to_space()->is_empty())) {
|
|
227 return;
|
|
228 }
|
|
229
|
|
230 if (PrintAdaptiveSizePolicy && Verbose) {
|
|
231 gclog_or_tty->print_cr("PSYoungGen::resize_spaces(requested_eden_size: "
|
|
232 SIZE_FORMAT
|
|
233 ", requested_survivor_size: " SIZE_FORMAT ")",
|
|
234 requested_eden_size, requested_survivor_size);
|
|
235 gclog_or_tty->print_cr(" eden: [" PTR_FORMAT ".." PTR_FORMAT ") "
|
|
236 SIZE_FORMAT,
|
|
237 eden_space()->bottom(),
|
|
238 eden_space()->end(),
|
|
239 pointer_delta(eden_space()->end(),
|
|
240 eden_space()->bottom(),
|
|
241 sizeof(char)));
|
|
242 gclog_or_tty->print_cr(" from: [" PTR_FORMAT ".." PTR_FORMAT ") "
|
|
243 SIZE_FORMAT,
|
|
244 from_space()->bottom(),
|
|
245 from_space()->end(),
|
|
246 pointer_delta(from_space()->end(),
|
|
247 from_space()->bottom(),
|
|
248 sizeof(char)));
|
|
249 gclog_or_tty->print_cr(" to: [" PTR_FORMAT ".." PTR_FORMAT ") "
|
|
250 SIZE_FORMAT,
|
|
251 to_space()->bottom(),
|
|
252 to_space()->end(),
|
|
253 pointer_delta( to_space()->end(),
|
|
254 to_space()->bottom(),
|
|
255 sizeof(char)));
|
|
256 }
|
|
257
|
|
258 // There's nothing to do if the new sizes are the same as the current
|
|
259 if (requested_survivor_size == to_space()->capacity_in_bytes() &&
|
|
260 requested_survivor_size == from_space()->capacity_in_bytes() &&
|
|
261 requested_eden_size == eden_space()->capacity_in_bytes()) {
|
|
262 if (PrintAdaptiveSizePolicy && Verbose) {
|
|
263 gclog_or_tty->print_cr(" capacities are the right sizes, returning");
|
|
264 }
|
|
265 return;
|
|
266 }
|
|
267
|
|
268 char* eden_start = (char*)virtual_space()->low();
|
|
269 char* eden_end = (char*)eden_space()->end();
|
|
270 char* from_start = (char*)from_space()->bottom();
|
|
271 char* from_end = (char*)from_space()->end();
|
|
272 char* to_start = (char*)to_space()->bottom();
|
|
273 char* to_end = (char*)to_space()->end();
|
|
274
|
|
275 assert(eden_start < from_start, "Cannot push into from_space");
|
|
276
|
|
277 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
|
|
278 const size_t alignment = heap->intra_generation_alignment();
|
|
279
|
|
280 // Check whether from space is below to space
|
|
281 if (from_start < to_start) {
|
|
282 // Eden, from, to
|
|
283 if (PrintAdaptiveSizePolicy && Verbose) {
|
|
284 gclog_or_tty->print_cr(" Eden, from, to:");
|
|
285 }
|
|
286
|
|
287 // Set eden
|
|
288 // Compute how big eden can be, then adjust end.
|
|
289 // See comment in PSYoungGen::resize_spaces() on
|
|
290 // calculating eden_end.
|
|
291 const size_t eden_size = MIN2(requested_eden_size,
|
|
292 pointer_delta(from_start,
|
|
293 eden_start,
|
|
294 sizeof(char)));
|
|
295 eden_end = eden_start + eden_size;
|
|
296 assert(eden_end >= eden_start, "addition overflowed")
|
|
297
|
|
298 // To may resize into from space as long as it is clear of live data.
|
|
299 // From space must remain page aligned, though, so we need to do some
|
|
300 // extra calculations.
|
|
301
|
|
302 // First calculate an optimal to-space
|
|
303 to_end = (char*)virtual_space()->high();
|
|
304 to_start = (char*)pointer_delta(to_end,
|
|
305 (char*)requested_survivor_size,
|
|
306 sizeof(char));
|
|
307
|
|
308 // Does the optimal to-space overlap from-space?
|
|
309 if (to_start < (char*)from_space()->end()) {
|
|
310 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
|
|
311
|
|
312 // Calculate the minimum offset possible for from_end
|
|
313 size_t from_size =
|
|
314 pointer_delta(from_space()->top(), from_start, sizeof(char));
|
|
315
|
|
316 // Should we be in this method if from_space is empty? Why not the set_space method? FIX ME!
|
|
317 if (from_size == 0) {
|
|
318 from_size = alignment;
|
|
319 } else {
|
|
320 from_size = align_size_up(from_size, alignment);
|
|
321 }
|
|
322
|
|
323 from_end = from_start + from_size;
|
|
324 assert(from_end > from_start, "addition overflow or from_size problem");
|
|
325
|
|
326 guarantee(from_end <= (char*)from_space()->end(),
|
|
327 "from_end moved to the right");
|
|
328
|
|
329 // Now update to_start with the new from_end
|
|
330 to_start = MAX2(from_end, to_start);
|
|
331 }
|
|
332
|
|
333 guarantee(to_start != to_end, "to space is zero sized");
|
|
334
|
|
335 if (PrintAdaptiveSizePolicy && Verbose) {
|
|
336 gclog_or_tty->print_cr(" [eden_start .. eden_end): "
|
|
337 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT,
|
|
338 eden_start,
|
|
339 eden_end,
|
|
340 pointer_delta(eden_end, eden_start, sizeof(char)));
|
|
341 gclog_or_tty->print_cr(" [from_start .. from_end): "
|
|
342 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT,
|
|
343 from_start,
|
|
344 from_end,
|
|
345 pointer_delta(from_end, from_start, sizeof(char)));
|
|
346 gclog_or_tty->print_cr(" [ to_start .. to_end): "
|
|
347 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT,
|
|
348 to_start,
|
|
349 to_end,
|
|
350 pointer_delta( to_end, to_start, sizeof(char)));
|
|
351 }
|
|
352 } else {
|
|
353 // Eden, to, from
|
|
354 if (PrintAdaptiveSizePolicy && Verbose) {
|
|
355 gclog_or_tty->print_cr(" Eden, to, from:");
|
|
356 }
|
|
357
|
|
358 // To space gets priority over eden resizing. Note that we position
|
|
359 // to space as if we were able to resize from space, even though from
|
|
360 // space is not modified.
|
|
361 // Giving eden priority was tried and gave poorer performance.
|
|
362 to_end = (char*)pointer_delta(virtual_space()->high(),
|
|
363 (char*)requested_survivor_size,
|
|
364 sizeof(char));
|
|
365 to_end = MIN2(to_end, from_start);
|
|
366 to_start = (char*)pointer_delta(to_end, (char*)requested_survivor_size,
|
|
367 sizeof(char));
|
|
368 // if the space sizes are to be increased by several times then
|
|
369 // 'to_start' will point beyond the young generation. In this case
|
|
370 // 'to_start' should be adjusted.
|
|
371 to_start = MAX2(to_start, eden_start + alignment);
|
|
372
|
|
373 // Compute how big eden can be, then adjust end.
|
|
374 // See comment in PSYoungGen::resize_spaces() on
|
|
375 // calculating eden_end.
|
|
376 const size_t eden_size = MIN2(requested_eden_size,
|
|
377 pointer_delta(to_start,
|
|
378 eden_start,
|
|
379 sizeof(char)));
|
|
380 eden_end = eden_start + eden_size;
|
|
381 assert(eden_end >= eden_start, "addition overflowed")
|
|
382
|
|
383 // Don't let eden shrink down to 0 or less.
|
|
384 eden_end = MAX2(eden_end, eden_start + alignment);
|
|
385 to_start = MAX2(to_start, eden_end);
|
|
386
|
|
387 if (PrintAdaptiveSizePolicy && Verbose) {
|
|
388 gclog_or_tty->print_cr(" [eden_start .. eden_end): "
|
|
389 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT,
|
|
390 eden_start,
|
|
391 eden_end,
|
|
392 pointer_delta(eden_end, eden_start, sizeof(char)));
|
|
393 gclog_or_tty->print_cr(" [ to_start .. to_end): "
|
|
394 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT,
|
|
395 to_start,
|
|
396 to_end,
|
|
397 pointer_delta( to_end, to_start, sizeof(char)));
|
|
398 gclog_or_tty->print_cr(" [from_start .. from_end): "
|
|
399 "[" PTR_FORMAT " .. " PTR_FORMAT ") " SIZE_FORMAT,
|
|
400 from_start,
|
|
401 from_end,
|
|
402 pointer_delta(from_end, from_start, sizeof(char)));
|
|
403 }
|
|
404 }
|
|
405
|
|
406
|
|
407 guarantee((HeapWord*)from_start <= from_space()->bottom(),
|
|
408 "from start moved to the right");
|
|
409 guarantee((HeapWord*)from_end >= from_space()->top(),
|
|
410 "from end moved into live data");
|
|
411 assert(is_object_aligned((intptr_t)eden_start), "checking alignment");
|
|
412 assert(is_object_aligned((intptr_t)from_start), "checking alignment");
|
|
413 assert(is_object_aligned((intptr_t)to_start), "checking alignment");
|
|
414
|
|
415 MemRegion edenMR((HeapWord*)eden_start, (HeapWord*)eden_end);
|
|
416 MemRegion toMR ((HeapWord*)to_start, (HeapWord*)to_end);
|
|
417 MemRegion fromMR((HeapWord*)from_start, (HeapWord*)from_end);
|
|
418
|
|
419 // Let's make sure the call to initialize doesn't reset "top"!
|
|
420 DEBUG_ONLY(HeapWord* old_from_top = from_space()->top();)
|
|
421
|
|
422 // For PrintAdaptiveSizePolicy block below
|
|
423 size_t old_from = from_space()->capacity_in_bytes();
|
|
424 size_t old_to = to_space()->capacity_in_bytes();
|
|
425
|
|
426 eden_space()->initialize(edenMR, true);
|
|
427 to_space()->initialize(toMR , true);
|
|
428 from_space()->initialize(fromMR, false); // Note, not cleared!
|
|
429 PSScavenge::set_young_generation_boundary(eden_space()->bottom());
|
|
430
|
|
431 assert(from_space()->top() == old_from_top, "from top changed!");
|
|
432
|
|
433 if (PrintAdaptiveSizePolicy) {
|
|
434 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
|
|
435 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
|
|
436
|
|
437 gclog_or_tty->print("AdaptiveSizePolicy::survivor space sizes: "
|
|
438 "collection: %d "
|
|
439 "(" SIZE_FORMAT ", " SIZE_FORMAT ") -> "
|
|
440 "(" SIZE_FORMAT ", " SIZE_FORMAT ") ",
|
|
441 heap->total_collections(),
|
|
442 old_from, old_to,
|
|
443 from_space()->capacity_in_bytes(),
|
|
444 to_space()->capacity_in_bytes());
|
|
445 gclog_or_tty->cr();
|
|
446 }
|
|
447 space_invariants();
|
|
448 }
|
|
449
|
|
450 void ASPSYoungGen::reset_after_change() {
|
|
451 assert_locked_or_safepoint(Heap_lock);
|
|
452
|
|
453 _reserved = MemRegion((HeapWord*)virtual_space()->low_boundary(),
|
|
454 (HeapWord*)virtual_space()->high_boundary());
|
|
455 PSScavenge::reference_processor()->set_span(_reserved);
|
|
456
|
|
457 HeapWord* new_eden_bottom = (HeapWord*)virtual_space()->low();
|
|
458 HeapWord* eden_bottom = eden_space()->bottom();
|
|
459 if (new_eden_bottom != eden_bottom) {
|
|
460 MemRegion eden_mr(new_eden_bottom, eden_space()->end());
|
|
461 eden_space()->initialize(eden_mr, true);
|
|
462 PSScavenge::set_young_generation_boundary(eden_space()->bottom());
|
|
463 }
|
|
464 MemRegion cmr((HeapWord*)virtual_space()->low(),
|
|
465 (HeapWord*)virtual_space()->high());
|
|
466 Universe::heap()->barrier_set()->resize_covered_region(cmr);
|
|
467
|
|
468 space_invariants();
|
|
469 }
|