/*
* Copyright 2001-2008 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*
*/
# include "incls/_precompiled.incl"
# include "incls/_parallelScavengeHeap.cpp.incl"
PSYoungGen* ParallelScavengeHeap::_young_gen = NULL;
PSOldGen* ParallelScavengeHeap::_old_gen = NULL;
PSPermGen* ParallelScavengeHeap::_perm_gen = NULL;
PSAdaptiveSizePolicy* ParallelScavengeHeap::_size_policy = NULL;
PSGCAdaptivePolicyCounters* ParallelScavengeHeap::_gc_policy_counters = NULL;
ParallelScavengeHeap* ParallelScavengeHeap::_psh = NULL;
GCTaskManager* ParallelScavengeHeap::_gc_task_manager = NULL;
static void trace_gen_sizes(const char* const str,
size_t pg_min, size_t pg_max,
size_t og_min, size_t og_max,
size_t yg_min, size_t yg_max)
{
if (TracePageSizes) {
tty->print_cr("%s: " SIZE_FORMAT "," SIZE_FORMAT " "
SIZE_FORMAT "," SIZE_FORMAT " "
SIZE_FORMAT "," SIZE_FORMAT " "
SIZE_FORMAT,
str, pg_min / K, pg_max / K,
og_min / K, og_max / K,
yg_min / K, yg_max / K,
(pg_max + og_max + yg_max) / K);
}
}
jint ParallelScavengeHeap::initialize() {
// Cannot be initialized until after the flags are parsed
GenerationSizer flag_parser;
size_t yg_min_size = flag_parser.min_young_gen_size();
size_t yg_max_size = flag_parser.max_young_gen_size();
size_t og_min_size = flag_parser.min_old_gen_size();
size_t og_max_size = flag_parser.max_old_gen_size();
// Why isn't there a min_perm_gen_size()?
size_t pg_min_size = flag_parser.perm_gen_size();
size_t pg_max_size = flag_parser.max_perm_gen_size();
trace_gen_sizes("ps heap raw",
pg_min_size, pg_max_size,
og_min_size, og_max_size,
yg_min_size, yg_max_size);
// The ReservedSpace ctor used below requires that the page size for the perm
// gen is <= the page size for the rest of the heap (young + old gens).
const size_t og_page_sz = os::page_size_for_region(yg_min_size + og_min_size,
yg_max_size + og_max_size,
8);
const size_t pg_page_sz = MIN2(os::page_size_for_region(pg_min_size,
pg_max_size, 16),
og_page_sz);
const size_t pg_align = set_alignment(_perm_gen_alignment, pg_page_sz);
const size_t og_align = set_alignment(_old_gen_alignment, og_page_sz);
const size_t yg_align = set_alignment(_young_gen_alignment, og_page_sz);
// Update sizes to reflect the selected page size(s).
//
// NEEDS_CLEANUP. The default TwoGenerationCollectorPolicy uses NewRatio; it
// should check UseAdaptiveSizePolicy. Changes from generationSizer could
// move to the common code.
yg_min_size = align_size_up(yg_min_size, yg_align);
yg_max_size = align_size_up(yg_max_size, yg_align);
size_t yg_cur_size = align_size_up(flag_parser.young_gen_size(), yg_align);
yg_cur_size = MAX2(yg_cur_size, yg_min_size);
og_min_size = align_size_up(og_min_size, og_align);
og_max_size = align_size_up(og_max_size, og_align);
size_t og_cur_size = align_size_up(flag_parser.old_gen_size(), og_align);
og_cur_size = MAX2(og_cur_size, og_min_size);
pg_min_size = align_size_up(pg_min_size, pg_align);
pg_max_size = align_size_up(pg_max_size, pg_align);
size_t pg_cur_size = pg_min_size;
trace_gen_sizes("ps heap rnd",
pg_min_size, pg_max_size,
og_min_size, og_max_size,
yg_min_size, yg_max_size);
// The main part of the heap (old gen + young gen) can often use a larger page
// size than is needed or wanted for the perm gen. Use the "compound
// alignment" ReservedSpace ctor to avoid having to use the same page size for
// all gens.
ReservedHeapSpace heap_rs(pg_max_size, pg_align, og_max_size + yg_max_size,
og_align);
os::trace_page_sizes("ps perm", pg_min_size, pg_max_size, pg_page_sz,
heap_rs.base(), pg_max_size);
os::trace_page_sizes("ps main", og_min_size + yg_min_size,
og_max_size + yg_max_size, og_page_sz,
heap_rs.base() + pg_max_size,
heap_rs.size() - pg_max_size);
if (!heap_rs.is_reserved()) {
vm_shutdown_during_initialization(
"Could not reserve enough space for object heap");
return JNI_ENOMEM;
}
_reserved = MemRegion((HeapWord*)heap_rs.base(),
(HeapWord*)(heap_rs.base() + heap_rs.size()));
CardTableExtension* const barrier_set = new CardTableExtension(_reserved, 3);
_barrier_set = barrier_set;
oopDesc::set_bs(_barrier_set);
if (_barrier_set == NULL) {
vm_shutdown_during_initialization(
"Could not reserve enough space for barrier set");
return JNI_ENOMEM;
}
// Initial young gen size is 4 Mb
//
// XXX - what about flag_parser.young_gen_size()?
const size_t init_young_size = align_size_up(4 * M, yg_align);
yg_cur_size = MAX2(MIN2(init_young_size, yg_max_size), yg_cur_size);
// Split the reserved space into perm gen and the main heap (everything else).
// The main heap uses a different alignment.
ReservedSpace perm_rs = heap_rs.first_part(pg_max_size);
ReservedSpace main_rs = heap_rs.last_part(pg_max_size, og_align);
// Make up the generations
// Calculate the maximum size that a generation can grow. This
// includes growth into the other generation. Note that the
// parameter _max_gen_size is kept as the maximum
// size of the generation as the boundaries currently stand.
// _max_gen_size is still used as that value.
double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0;
double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0;
_gens = new AdjoiningGenerations(main_rs,
og_cur_size,
og_min_size,
og_max_size,
yg_cur_size,
yg_min_size,
yg_max_size,
yg_align);
_old_gen = _gens->old_gen();
_young_gen = _gens->young_gen();
const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes();
const size_t old_capacity = _old_gen->capacity_in_bytes();
const size_t initial_promo_size = MIN2(eden_capacity, old_capacity);
_size_policy =
new PSAdaptiveSizePolicy(eden_capacity,
initial_promo_size,
young_gen()->to_space()->capacity_in_bytes(),
intra_heap_alignment(),
max_gc_pause_sec,
max_gc_minor_pause_sec,
GCTimeRatio
);
_perm_gen = new PSPermGen(perm_rs,
pg_align,
pg_cur_size,
pg_cur_size,
pg_max_size,
"perm", 2);
assert(!UseAdaptiveGCBoundary ||
(old_gen()->virtual_space()->high_boundary() ==
young_gen()->virtual_space()->low_boundary()),
"Boundaries must meet");
// initialize the policy counters - 2 collectors, 3 generations
_gc_policy_counters =
new PSGCAdaptivePolicyCounters("ParScav:MSC", 2, 3, _size_policy);
_psh = this;
// Set up the GCTaskManager
_gc_task_manager = GCTaskManager::create(ParallelGCThreads);
if (UseParallelOldGC && !PSParallelCompact::initialize()) {
return JNI_ENOMEM;
}
return JNI_OK;
}
void ParallelScavengeHeap::post_initialize() {
// Need to init the tenuring threshold
PSScavenge::initialize();
if (UseParallelOldGC) {
PSParallelCompact::post_initialize();
if (VerifyParallelOldWithMarkSweep) {
// Will be used for verification of par old.
PSMarkSweep::initialize();
}
} else {
PSMarkSweep::initialize();
}
PSPromotionManager::initialize();
}
void ParallelScavengeHeap::update_counters() {
young_gen()->update_counters();
old_gen()->update_counters();
perm_gen()->update_counters();
}
size_t ParallelScavengeHeap::capacity() const {
size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes();
return value;
}
size_t ParallelScavengeHeap::used() const {
size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes();
return value;
}
bool ParallelScavengeHeap::is_maximal_no_gc() const {
return old_gen()->is_maximal_no_gc() && young_gen()->is_maximal_no_gc();
}
size_t ParallelScavengeHeap::permanent_capacity() const {
return perm_gen()->capacity_in_bytes();
}
size_t ParallelScavengeHeap::permanent_used() const {
return perm_gen()->used_in_bytes();
}
size_t ParallelScavengeHeap::max_capacity() const {
size_t estimated = reserved_region().byte_size();
estimated -= perm_gen()->reserved().byte_size();
if (UseAdaptiveSizePolicy) {
estimated -= _size_policy->max_survivor_size(young_gen()->max_size());
} else {
estimated -= young_gen()->to_space()->capacity_in_bytes();
}
return MAX2(estimated, capacity());
}
bool ParallelScavengeHeap::is_in(const void* p) const {
if (young_gen()->is_in(p)) {
return true;
}
if (old_gen()->is_in(p)) {
return true;
}
if (perm_gen()->is_in(p)) {
return true;
}
return false;
}
bool ParallelScavengeHeap::is_in_reserved(const void* p) const {
if (young_gen()->is_in_reserved(p)) {
return true;
}
if (old_gen()->is_in_reserved(p)) {
return true;
}
if (perm_gen()->is_in_reserved(p)) {
return true;
}
return false;
}
// Static method
bool ParallelScavengeHeap::is_in_young(oop* p) {
ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
assert(heap->kind() == CollectedHeap::ParallelScavengeHeap,
"Must be ParallelScavengeHeap");
PSYoungGen* young_gen = heap->young_gen();
if (young_gen->is_in_reserved(p)) {
return true;
}
return false;
}
// Static method
bool ParallelScavengeHeap::is_in_old_or_perm(oop* p) {
ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
assert(heap->kind() == CollectedHeap::ParallelScavengeHeap,
"Must be ParallelScavengeHeap");
PSOldGen* old_gen = heap->old_gen();
PSPermGen* perm_gen = heap->perm_gen();
if (old_gen->is_in_reserved(p)) {
return true;
}
if (perm_gen->is_in_reserved(p)) {
return true;
}
return false;
}
// There are two levels of allocation policy here.
//
// When an allocation request fails, the requesting thread must invoke a VM
// operation, transfer control to the VM thread, and await the results of a
// garbage collection. That is quite expensive, and we should avoid doing it
// multiple times if possible.
//
// To accomplish this, we have a basic allocation policy, and also a
// failed allocation policy.
//
// The basic allocation policy controls how you allocate memory without
// attempting garbage collection. It is okay to grab locks and
// expand the heap, if that can be done without coming to a safepoint.
// It is likely that the basic allocation policy will not be very
// aggressive.
//
// The failed allocation policy is invoked from the VM thread after
// the basic allocation policy is unable to satisfy a mem_allocate
// request. This policy needs to cover the entire range of collection,
// heap expansion, and out-of-memory conditions. It should make every
// attempt to allocate the requested memory.
// Basic allocation policy. Should never be called at a safepoint, or
// from the VM thread.
//
// This method must handle cases where many mem_allocate requests fail
// simultaneously. When that happens, only one VM operation will succeed,
// and the rest will not be executed. For that reason, this method loops
// during failed allocation attempts. If the java heap becomes exhausted,
// we rely on the size_policy object to force a bail out.
HeapWord* ParallelScavengeHeap::mem_allocate(
size_t size,
bool is_noref,
bool is_tlab,
bool* gc_overhead_limit_was_exceeded) {
assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint");
assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread");
assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
HeapWord* result = young_gen()->allocate(size, is_tlab);
uint loop_count = 0;
uint gc_count = 0;
while (result == NULL) {
// We don't want to have multiple collections for a single filled generation.
// To prevent this, each thread tracks the total_collections() value, and if
// the count has changed, does not do a new collection.
//
// The collection count must be read only while holding the heap lock. VM
// operations also hold the heap lock during collections. There is a lock
// contention case where thread A blocks waiting on the Heap_lock, while
// thread B is holding it doing a collection. When thread A gets the lock,
// the collection count has already changed. To prevent duplicate collections,
// The policy MUST attempt allocations during the same period it reads the
// total_collections() value!
{
MutexLocker ml(Heap_lock);
gc_count = Universe::heap()->total_collections();
result = young_gen()->allocate(size, is_tlab);
// (1) If the requested object is too large to easily fit in the
// young_gen, or
// (2) If GC is locked out via GCLocker, young gen is full and
// the need for a GC already signalled to GCLocker (done
// at a safepoint),
// ... then, rather than force a safepoint and (a potentially futile)
// collection (attempt) for each allocation, try allocation directly
// in old_gen. For case (2) above, we may in the future allow
// TLAB allocation directly in the old gen.
if (result != NULL) {
return result;
}
if (!is_tlab &&
size >= (young_gen()->eden_space()->capacity_in_words() / 2)) {
result = old_gen()->allocate(size, is_tlab);
if (result != NULL) {
return result;
}
}
if (GC_locker::is_active_and_needs_gc()) {
// GC is locked out. If this is a TLAB allocation,
// return NULL; the requestor will retry allocation
// of an idividual object at a time.
if (is_tlab) {
return NULL;
}
// If this thread is not in a jni critical section, we stall
// the requestor until the critical section has cleared and
// GC allowed. When the critical section clears, a GC is
// initiated by the last thread exiting the critical section; so
// we retry the allocation sequence from the beginning of the loop,
// rather than causing more, now probably unnecessary, GC attempts.
JavaThread* jthr = JavaThread::current();
if (!jthr->in_critical()) {
MutexUnlocker mul(Heap_lock);
GC_locker::stall_until_clear();
continue;
} else {
if (CheckJNICalls) {
fatal("Possible deadlock due to allocating while"
" in jni critical section");
}
return NULL;
}
}
}
if (result == NULL) {
// Exit the loop if if the gc time limit has been exceeded.
// The allocation must have failed above (result must be NULL),
// and the most recent collection must have exceeded the
// gc time limit. Exit the loop so that an out-of-memory
// will be thrown (returning a NULL will do that), but
// clear gc_time_limit_exceeded so that the next collection
// will succeeded if the applications decides to handle the
// out-of-memory and tries to go on.
*gc_overhead_limit_was_exceeded = size_policy()->gc_time_limit_exceeded();
if (size_policy()->gc_time_limit_exceeded()) {
size_policy()->set_gc_time_limit_exceeded(false);
if (PrintGCDetails && Verbose) {
gclog_or_tty->print_cr("ParallelScavengeHeap::mem_allocate: "
"return NULL because gc_time_limit_exceeded is set");
}
return NULL;
}
// Generate a VM operation
VM_ParallelGCFailedAllocation op(size, is_tlab, gc_count);
VMThread::execute(&op);
// Did the VM operation execute? If so, return the result directly.
// This prevents us from looping until time out on requests that can
// not be satisfied.
if (op.prologue_succeeded()) {
assert(Universe::heap()->is_in_or_null(op.result()),
"result not in heap");
// If GC was locked out during VM operation then retry allocation
// and/or stall as necessary.
if (op.gc_locked()) {
assert(op.result() == NULL, "must be NULL if gc_locked() is true");
continue; // retry and/or stall as necessary
}
// If a NULL result is being returned, an out-of-memory
// will be thrown now. Clear the gc_time_limit_exceeded
// flag to avoid the following situation.
// gc_time_limit_exceeded is set during a collection
// the collection fails to return enough space and an OOM is thrown
// the next GC is skipped because the gc_time_limit_exceeded
// flag is set and another OOM is thrown
if (op.result() == NULL) {
size_policy()->set_gc_time_limit_exceeded(false);
}
return op.result();
}
}
// The policy object will prevent us from looping forever. If the
// time spent in gc crosses a threshold, we will bail out.
loop_count++;
if ((result == NULL) && (QueuedAllocationWarningCount > 0) &&
(loop_count % QueuedAllocationWarningCount == 0)) {
warning("ParallelScavengeHeap::mem_allocate retries %d times \n\t"
" size=%d %s", loop_count, size, is_tlab ? "(TLAB)" : "");
}
}
return result;
}
// Failed allocation policy. Must be called from the VM thread, and
// only at a safepoint! Note that this method has policy for allocation
// flow, and NOT collection policy. So we do not check for gc collection
// time over limit here, that is the responsibility of the heap specific
// collection methods. This method decides where to attempt allocations,
// and when to attempt collections, but no collection specific policy.
HeapWord* ParallelScavengeHeap::failed_mem_allocate(size_t size, bool is_tlab) {
assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
assert(!Universe::heap()->is_gc_active(), "not reentrant");
assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
size_t mark_sweep_invocation_count = total_invocations();
// We assume (and assert!) that an allocation at this point will fail
// unless we collect.
// First level allocation failure, scavenge and allocate in young gen.
GCCauseSetter gccs(this, GCCause::_allocation_failure);
PSScavenge::invoke();
HeapWord* result = young_gen()->allocate(size, is_tlab);
// Second level allocation failure.
// Mark sweep and allocate in young generation.
if (result == NULL) {
// There is some chance the scavenge method decided to invoke mark_sweep.
// Don't mark sweep twice if so.
if (mark_sweep_invocation_count == total_invocations()) {
invoke_full_gc(false);
result = young_gen()->allocate(size, is_tlab);
}
}
// Third level allocation failure.
// After mark sweep and young generation allocation failure,
// allocate in old generation.
if (result == NULL && !is_tlab) {
result = old_gen()->allocate(size, is_tlab);
}
// Fourth level allocation failure. We're running out of memory.
// More complete mark sweep and allocate in young generation.
if (result == NULL) {
invoke_full_gc(true);
result = young_gen()->allocate(size, is_tlab);
}
// Fifth level allocation failure.
// After more complete mark sweep, allocate in old generation.
if (result == NULL && !is_tlab) {
result = old_gen()->allocate(size, is_tlab);
}
return result;
}
//
// This is the policy loop for allocating in the permanent generation.
// If the initial allocation fails, we create a vm operation which will
// cause a collection.
HeapWord* ParallelScavengeHeap::permanent_mem_allocate(size_t size) {
assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint");
assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread");
assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
HeapWord* result;
uint loop_count = 0;
uint gc_count = 0;
uint full_gc_count = 0;
do {
// We don't want to have multiple collections for a single filled generation.
// To prevent this, each thread tracks the total_collections() value, and if
// the count has changed, does not do a new collection.
//
// The collection count must be read only while holding the heap lock. VM
// operations also hold the heap lock during collections. There is a lock
// contention case where thread A blocks waiting on the Heap_lock, while
// thread B is holding it doing a collection. When thread A gets the lock,
// the collection count has already changed. To prevent duplicate collections,
// The policy MUST attempt allocations during the same period it reads the
// total_collections() value!
{
MutexLocker ml(Heap_lock);
gc_count = Universe::heap()->total_collections();
full_gc_count = Universe::heap()->total_full_collections();
result = perm_gen()->allocate_permanent(size);
if (result != NULL) {
return result;
}
if (GC_locker::is_active_and_needs_gc()) {
// If this thread is not in a jni critical section, we stall
// the requestor until the critical section has cleared and
// GC allowed. When the critical section clears, a GC is
// initiated by the last thread exiting the critical section; so
// we retry the allocation sequence from the beginning of the loop,
// rather than causing more, now probably unnecessary, GC attempts.
JavaThread* jthr = JavaThread::current();
if (!jthr->in_critical()) {
MutexUnlocker mul(Heap_lock);
GC_locker::stall_until_clear();
continue;
} else {
if (CheckJNICalls) {
fatal("Possible deadlock due to allocating while"
" in jni critical section");
}
return NULL;
}
}
}
if (result == NULL) {
// Exit the loop if the gc time limit has been exceeded.
// The allocation must have failed above (result must be NULL),
// and the most recent collection must have exceeded the
// gc time limit. Exit the loop so that an out-of-memory
// will be thrown (returning a NULL will do that), but
// clear gc_time_limit_exceeded so that the next collection
// will succeeded if the applications decides to handle the
// out-of-memory and tries to go on.
if (size_policy()->gc_time_limit_exceeded()) {
size_policy()->set_gc_time_limit_exceeded(false);
if (PrintGCDetails && Verbose) {
gclog_or_tty->print_cr("ParallelScavengeHeap::permanent_mem_allocate: "
"return NULL because gc_time_limit_exceeded is set");
}
assert(result == NULL, "Allocation did not fail");
return NULL;
}
// Generate a VM operation
VM_ParallelGCFailedPermanentAllocation op(size, gc_count, full_gc_count);
VMThread::execute(&op);
// Did the VM operation execute? If so, return the result directly.
// This prevents us from looping until time out on requests that can
// not be satisfied.
if (op.prologue_succeeded()) {
assert(Universe::heap()->is_in_permanent_or_null(op.result()),
"result not in heap");
// If GC was locked out during VM operation then retry allocation
// and/or stall as necessary.
if (op.gc_locked()) {
assert(op.result() == NULL, "must be NULL if gc_locked() is true");
continue; // retry and/or stall as necessary
}
// If a NULL results is being returned, an out-of-memory
// will be thrown now. Clear the gc_time_limit_exceeded
// flag to avoid the following situation.
// gc_time_limit_exceeded is set during a collection
// the collection fails to return enough space and an OOM is thrown
// the next GC is skipped because the gc_time_limit_exceeded
// flag is set and another OOM is thrown
if (op.result() == NULL) {
size_policy()->set_gc_time_limit_exceeded(false);
}
return op.result();
}
}
// The policy object will prevent us from looping forever. If the
// time spent in gc crosses a threshold, we will bail out.
loop_count++;
if ((QueuedAllocationWarningCount > 0) &&
(loop_count % QueuedAllocationWarningCount == 0)) {
warning("ParallelScavengeHeap::permanent_mem_allocate retries %d times \n\t"
" size=%d", loop_count, size);
}
} while (result == NULL);
return result;
}
//
// This is the policy code for permanent allocations which have failed
// and require a collection. Note that just as in failed_mem_allocate,
// we do not set collection policy, only where & when to allocate and
// collect.
HeapWord* ParallelScavengeHeap::failed_permanent_mem_allocate(size_t size) {
assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
assert(!Universe::heap()->is_gc_active(), "not reentrant");
assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
assert(size > perm_gen()->free_in_words(), "Allocation should fail");
// We assume (and assert!) that an allocation at this point will fail
// unless we collect.
// First level allocation failure. Mark-sweep and allocate in perm gen.
GCCauseSetter gccs(this, GCCause::_allocation_failure);
invoke_full_gc(false);
HeapWord* result = perm_gen()->allocate_permanent(size);
// Second level allocation failure. We're running out of memory.
if (result == NULL) {
invoke_full_gc(true);
result = perm_gen()->allocate_permanent(size);
}
return result;
}
void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) {
CollectedHeap::ensure_parsability(retire_tlabs);
young_gen()->eden_space()->ensure_parsability();
}
size_t ParallelScavengeHeap::unsafe_max_alloc() {
return young_gen()->eden_space()->free_in_bytes();
}
size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const {
return young_gen()->eden_space()->tlab_capacity(thr);
}
size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const {
return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr);
}
HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t size) {
return young_gen()->allocate(size, true);
}
void ParallelScavengeHeap::fill_all_tlabs(bool retire) {
CollectedHeap::fill_all_tlabs(retire);
}
void ParallelScavengeHeap::accumulate_statistics_all_tlabs() {
CollectedHeap::accumulate_statistics_all_tlabs();
}
void ParallelScavengeHeap::resize_all_tlabs() {
CollectedHeap::resize_all_tlabs();
}
// This method is used by System.gc() and JVMTI.
void ParallelScavengeHeap::collect(GCCause::Cause cause) {
assert(!Heap_lock->owned_by_self(),
"this thread should not own the Heap_lock");
unsigned int gc_count = 0;
unsigned int full_gc_count = 0;
{
MutexLocker ml(Heap_lock);
// This value is guarded by the Heap_lock
gc_count = Universe::heap()->total_collections();
full_gc_count = Universe::heap()->total_full_collections();
}
VM_ParallelGCSystemGC op(gc_count, full_gc_count, cause);
VMThread::execute(&op);
}
// This interface assumes that it's being called by the
// vm thread. It collects the heap assuming that the
// heap lock is already held and that we are executing in
// the context of the vm thread.
void ParallelScavengeHeap::collect_as_vm_thread(GCCause::Cause cause) {
assert(Thread::current()->is_VM_thread(), "Precondition#1");
assert(Heap_lock->is_locked(), "Precondition#2");
GCCauseSetter gcs(this, cause);
switch (cause) {
case GCCause::_heap_inspection:
case GCCause::_heap_dump: {
HandleMark hm;
invoke_full_gc(false);
break;
}
default: // XXX FIX ME
ShouldNotReachHere();
}
}
void ParallelScavengeHeap::oop_iterate(OopClosure* cl) {
Unimplemented();
}
void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) {
young_gen()->object_iterate(cl);
old_gen()->object_iterate(cl);
perm_gen()->object_iterate(cl);
}
void ParallelScavengeHeap::permanent_oop_iterate(OopClosure* cl) {
Unimplemented();
}
void ParallelScavengeHeap::permanent_object_iterate(ObjectClosure* cl) {
perm_gen()->object_iterate(cl);
}
HeapWord* ParallelScavengeHeap::block_start(const void* addr) const {
if (young_gen()->is_in_reserved(addr)) {
assert(young_gen()->is_in(addr),
"addr should be in allocated part of young gen");
Unimplemented();
} else if (old_gen()->is_in_reserved(addr)) {
assert(old_gen()->is_in(addr),
"addr should be in allocated part of old gen");
return old_gen()->start_array()->object_start((HeapWord*)addr);
} else if (perm_gen()->is_in_reserved(addr)) {
assert(perm_gen()->is_in(addr),
"addr should be in allocated part of perm gen");
return perm_gen()->start_array()->object_start((HeapWord*)addr);
}
return 0;
}
size_t ParallelScavengeHeap::block_size(const HeapWord* addr) const {
return oop(addr)->size();
}
bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const {
return block_start(addr) == addr;
}
jlong ParallelScavengeHeap::millis_since_last_gc() {
return UseParallelOldGC ?
PSParallelCompact::millis_since_last_gc() :
PSMarkSweep::millis_since_last_gc();
}
void ParallelScavengeHeap::prepare_for_verify() {
ensure_parsability(false); // no need to retire TLABs for verification
}
void ParallelScavengeHeap::print() const { print_on(tty); }
void ParallelScavengeHeap::print_on(outputStream* st) const {
young_gen()->print_on(st);
old_gen()->print_on(st);
perm_gen()->print_on(st);
}
void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const {
PSScavenge::gc_task_manager()->threads_do(tc);
}
void ParallelScavengeHeap::print_gc_threads_on(outputStream* st) const {
PSScavenge::gc_task_manager()->print_threads_on(st);
}
void ParallelScavengeHeap::print_tracing_info() const {
if (TraceGen0Time) {
double time = PSScavenge::accumulated_time()->seconds();
tty->print_cr("[Accumulated GC generation 0 time %3.7f secs]", time);
}
if (TraceGen1Time) {
double time = PSMarkSweep::accumulated_time()->seconds();
tty->print_cr("[Accumulated GC generation 1 time %3.7f secs]", time);
}
}
void ParallelScavengeHeap::verify(bool allow_dirty, bool silent) {
// Why do we need the total_collections()-filter below?
if (total_collections() > 0) {
if (!silent) {
gclog_or_tty->print("permanent ");
}
perm_gen()->verify(allow_dirty);
if (!silent) {
gclog_or_tty->print("tenured ");
}
old_gen()->verify(allow_dirty);
if (!silent) {
gclog_or_tty->print("eden ");
}
young_gen()->verify(allow_dirty);
}
if (!silent) {
gclog_or_tty->print("ref_proc ");
}
ReferenceProcessor::verify();
}
void ParallelScavengeHeap::print_heap_change(size_t prev_used) {
if (PrintGCDetails && Verbose) {
gclog_or_tty->print(" " SIZE_FORMAT
"->" SIZE_FORMAT
"(" SIZE_FORMAT ")",
prev_used, used(), capacity());
} else {
gclog_or_tty->print(" " SIZE_FORMAT "K"
"->" SIZE_FORMAT "K"
"(" SIZE_FORMAT "K)",
prev_used / K, used() / K, capacity() / K);
}
}
ParallelScavengeHeap* ParallelScavengeHeap::heap() {
assert(_psh != NULL, "Uninitialized access to ParallelScavengeHeap::heap()");
assert(_psh->kind() == CollectedHeap::ParallelScavengeHeap, "not a parallel scavenge heap");
return _psh;
}
// Before delegating the resize to the young generation,
// the reserved space for the young and old generations
// may be changed to accomodate the desired resize.
void ParallelScavengeHeap::resize_young_gen(size_t eden_size,
size_t survivor_size) {
if (UseAdaptiveGCBoundary) {
if (size_policy()->bytes_absorbed_from_eden() != 0) {
size_policy()->reset_bytes_absorbed_from_eden();
return; // The generation changed size already.
}
gens()->adjust_boundary_for_young_gen_needs(eden_size, survivor_size);
}
// Delegate the resize to the generation.
_young_gen->resize(eden_size, survivor_size);
}
// Before delegating the resize to the old generation,
// the reserved space for the young and old generations
// may be changed to accomodate the desired resize.
void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) {
if (UseAdaptiveGCBoundary) {
if (size_policy()->bytes_absorbed_from_eden() != 0) {
size_policy()->reset_bytes_absorbed_from_eden();
return; // The generation changed size already.
}
gens()->adjust_boundary_for_old_gen_needs(desired_free_space);
}
// Delegate the resize to the generation.
_old_gen->resize(desired_free_space);
}
#ifndef PRODUCT
void ParallelScavengeHeap::record_gen_tops_before_GC() {
if (ZapUnusedHeapArea) {
young_gen()->record_spaces_top();
old_gen()->record_spaces_top();
perm_gen()->record_spaces_top();
}
}
void ParallelScavengeHeap::gen_mangle_unused_area() {
if (ZapUnusedHeapArea) {
young_gen()->eden_space()->mangle_unused_area();
young_gen()->to_space()->mangle_unused_area();
young_gen()->from_space()->mangle_unused_area();
old_gen()->object_space()->mangle_unused_area();
perm_gen()->object_space()->mangle_unused_area();
}
}
#endif