551 lines
22 KiB
C++
551 lines
22 KiB
C++
|
/*
|
||
|
|
* Copyright 2001-2007 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/_collectorPolicy.cpp.incl"
|
||
|
|
|
||
|
|
// CollectorPolicy methods.
|
||
|
|
|
||
|
|
void CollectorPolicy::initialize_flags() {
|
||
|
|
if (PermSize > MaxPermSize) {
|
||
|
|
MaxPermSize = PermSize;
|
||
|
|
}
|
||
|
|
PermSize = align_size_down(PermSize, min_alignment());
|
||
|
|
MaxPermSize = align_size_up(MaxPermSize, max_alignment());
|
||
|
|
|
||
|
|
MinPermHeapExpansion = align_size_down(MinPermHeapExpansion, min_alignment());
|
||
|
|
MaxPermHeapExpansion = align_size_down(MaxPermHeapExpansion, min_alignment());
|
||
|
|
|
||
|
|
MinHeapDeltaBytes = align_size_up(MinHeapDeltaBytes, min_alignment());
|
||
|
|
|
||
|
|
SharedReadOnlySize = align_size_up(SharedReadOnlySize, max_alignment());
|
||
|
|
SharedReadWriteSize = align_size_up(SharedReadWriteSize, max_alignment());
|
||
|
|
SharedMiscDataSize = align_size_up(SharedMiscDataSize, max_alignment());
|
||
|
|
|
||
|
|
assert(PermSize % min_alignment() == 0, "permanent space alignment");
|
||
|
|
assert(MaxPermSize % max_alignment() == 0, "maximum permanent space alignment");
|
||
|
|
assert(SharedReadOnlySize % max_alignment() == 0, "read-only space alignment");
|
||
|
|
assert(SharedReadWriteSize % max_alignment() == 0, "read-write space alignment");
|
||
|
|
assert(SharedMiscDataSize % max_alignment() == 0, "misc-data space alignment");
|
||
|
|
if (PermSize < M) {
|
||
|
|
vm_exit_during_initialization("Too small initial permanent heap");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void CollectorPolicy::initialize_size_info() {
|
||
|
|
// User inputs from -mx and ms are aligned
|
||
|
|
_initial_heap_byte_size = align_size_up(Arguments::initial_heap_size(),
|
||
|
|
min_alignment());
|
||
|
|
_min_heap_byte_size = align_size_up(Arguments::min_heap_size(),
|
||
|
|
min_alignment());
|
||
|
|
_max_heap_byte_size = align_size_up(MaxHeapSize, max_alignment());
|
||
|
|
|
||
|
|
// Check validity of heap parameters from launcher
|
||
|
|
if (_initial_heap_byte_size == 0) {
|
||
|
|
_initial_heap_byte_size = NewSize + OldSize;
|
||
|
|
} else {
|
||
|
|
Universe::check_alignment(_initial_heap_byte_size, min_alignment(),
|
||
|
|
"initial heap");
|
||
|
|
}
|
||
|
|
if (_min_heap_byte_size == 0) {
|
||
|
|
_min_heap_byte_size = NewSize + OldSize;
|
||
|
|
} else {
|
||
|
|
Universe::check_alignment(_min_heap_byte_size, min_alignment(),
|
||
|
|
"initial heap");
|
||
|
|
}
|
||
|
|
|
||
|
|
// Check heap parameter properties
|
||
|
|
if (_initial_heap_byte_size < M) {
|
||
|
|
vm_exit_during_initialization("Too small initial heap");
|
||
|
|
}
|
||
|
|
// Check heap parameter properties
|
||
|
|
if (_min_heap_byte_size < M) {
|
||
|
|
vm_exit_during_initialization("Too small minimum heap");
|
||
|
|
}
|
||
|
|
if (_initial_heap_byte_size <= NewSize) {
|
||
|
|
// make sure there is at least some room in old space
|
||
|
|
vm_exit_during_initialization("Too small initial heap for new size specified");
|
||
|
|
}
|
||
|
|
if (_max_heap_byte_size < _min_heap_byte_size) {
|
||
|
|
vm_exit_during_initialization("Incompatible minimum and maximum heap sizes specified");
|
||
|
|
}
|
||
|
|
if (_initial_heap_byte_size < _min_heap_byte_size) {
|
||
|
|
vm_exit_during_initialization("Incompatible minimum and initial heap sizes specified");
|
||
|
|
}
|
||
|
|
if (_max_heap_byte_size < _initial_heap_byte_size) {
|
||
|
|
vm_exit_during_initialization("Incompatible initial and maximum heap sizes specified");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void CollectorPolicy::initialize_perm_generation(PermGen::Name pgnm) {
|
||
|
|
_permanent_generation =
|
||
|
|
new PermanentGenerationSpec(pgnm, PermSize, MaxPermSize,
|
||
|
|
SharedReadOnlySize,
|
||
|
|
SharedReadWriteSize,
|
||
|
|
SharedMiscDataSize,
|
||
|
|
SharedMiscCodeSize);
|
||
|
|
if (_permanent_generation == NULL) {
|
||
|
|
vm_exit_during_initialization("Unable to allocate gen spec");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
GenRemSet* CollectorPolicy::create_rem_set(MemRegion whole_heap,
|
||
|
|
int max_covered_regions) {
|
||
|
|
switch (rem_set_name()) {
|
||
|
|
case GenRemSet::CardTable: {
|
||
|
|
if (barrier_set_name() != BarrierSet::CardTableModRef)
|
||
|
|
vm_exit_during_initialization("Mismatch between RS and BS.");
|
||
|
|
CardTableRS* res = new CardTableRS(whole_heap, max_covered_regions);
|
||
|
|
return res;
|
||
|
|
}
|
||
|
|
default:
|
||
|
|
guarantee(false, "unrecognized GenRemSet::Name");
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// GenCollectorPolicy methods.
|
||
|
|
|
||
|
|
void GenCollectorPolicy::initialize_size_policy(size_t init_eden_size,
|
||
|
|
size_t init_promo_size,
|
||
|
|
size_t init_survivor_size) {
|
||
|
|
double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0;
|
||
|
|
_size_policy = new AdaptiveSizePolicy(init_eden_size,
|
||
|
|
init_promo_size,
|
||
|
|
init_survivor_size,
|
||
|
|
max_gc_minor_pause_sec,
|
||
|
|
GCTimeRatio);
|
||
|
|
}
|
||
|
|
|
||
|
|
size_t GenCollectorPolicy::compute_max_alignment() {
|
||
|
|
// The card marking array and the offset arrays for old generations are
|
||
|
|
// committed in os pages as well. Make sure they are entirely full (to
|
||
|
|
// avoid partial page problems), e.g. if 512 bytes heap corresponds to 1
|
||
|
|
// byte entry and the os page size is 4096, the maximum heap size should
|
||
|
|
// be 512*4096 = 2MB aligned.
|
||
|
|
size_t alignment = GenRemSet::max_alignment_constraint(rem_set_name());
|
||
|
|
|
||
|
|
// Parallel GC does its own alignment of the generations to avoid requiring a
|
||
|
|
// large page (256M on some platforms) for the permanent generation. The
|
||
|
|
// other collectors should also be updated to do their own alignment and then
|
||
|
|
// this use of lcm() should be removed.
|
||
|
|
if (UseLargePages && !UseParallelGC) {
|
||
|
|
// in presence of large pages we have to make sure that our
|
||
|
|
// alignment is large page aware
|
||
|
|
alignment = lcm(os::large_page_size(), alignment);
|
||
|
|
}
|
||
|
|
|
||
|
|
return alignment;
|
||
|
|
}
|
||
|
|
|
||
|
|
void GenCollectorPolicy::initialize_flags() {
|
||
|
|
// All sizes must be multiples of the generation granularity.
|
||
|
|
set_min_alignment((uintx) Generation::GenGrain);
|
||
|
|
set_max_alignment(compute_max_alignment());
|
||
|
|
assert(max_alignment() >= min_alignment() &&
|
||
|
|
max_alignment() % min_alignment() == 0,
|
||
|
|
"invalid alignment constraints");
|
||
|
|
|
||
|
|
CollectorPolicy::initialize_flags();
|
||
|
|
|
||
|
|
// All generational heaps have a youngest gen; handle those flags here.
|
||
|
|
|
||
|
|
// Adjust max size parameters
|
||
|
|
if (NewSize > MaxNewSize) {
|
||
|
|
MaxNewSize = NewSize;
|
||
|
|
}
|
||
|
|
NewSize = align_size_down(NewSize, min_alignment());
|
||
|
|
MaxNewSize = align_size_down(MaxNewSize, min_alignment());
|
||
|
|
|
||
|
|
// Check validity of heap flags
|
||
|
|
assert(NewSize % min_alignment() == 0, "eden space alignment");
|
||
|
|
assert(MaxNewSize % min_alignment() == 0, "survivor space alignment");
|
||
|
|
|
||
|
|
if (NewSize < 3*min_alignment()) {
|
||
|
|
// make sure there room for eden and two survivor spaces
|
||
|
|
vm_exit_during_initialization("Too small new size specified");
|
||
|
|
}
|
||
|
|
if (SurvivorRatio < 1 || NewRatio < 1) {
|
||
|
|
vm_exit_during_initialization("Invalid heap ratio specified");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void TwoGenerationCollectorPolicy::initialize_flags() {
|
||
|
|
GenCollectorPolicy::initialize_flags();
|
||
|
|
|
||
|
|
OldSize = align_size_down(OldSize, min_alignment());
|
||
|
|
if (NewSize + OldSize > MaxHeapSize) {
|
||
|
|
MaxHeapSize = NewSize + OldSize;
|
||
|
|
}
|
||
|
|
MaxHeapSize = align_size_up(MaxHeapSize, max_alignment());
|
||
|
|
|
||
|
|
always_do_update_barrier = UseConcMarkSweepGC;
|
||
|
|
BlockOffsetArrayUseUnallocatedBlock =
|
||
|
|
BlockOffsetArrayUseUnallocatedBlock || ParallelGCThreads > 0;
|
||
|
|
|
||
|
|
// Check validity of heap flags
|
||
|
|
assert(OldSize % min_alignment() == 0, "old space alignment");
|
||
|
|
assert(MaxHeapSize % max_alignment() == 0, "maximum heap alignment");
|
||
|
|
}
|
||
|
|
|
||
|
|
void GenCollectorPolicy::initialize_size_info() {
|
||
|
|
CollectorPolicy::initialize_size_info();
|
||
|
|
|
||
|
|
// Minimum sizes of the generations may be different than
|
||
|
|
// the initial sizes.
|
||
|
|
if (!FLAG_IS_DEFAULT(NewSize)) {
|
||
|
|
_min_gen0_size = NewSize;
|
||
|
|
} else {
|
||
|
|
_min_gen0_size = align_size_down(_min_heap_byte_size / (NewRatio+1),
|
||
|
|
min_alignment());
|
||
|
|
// We bound the minimum size by NewSize below (since it historically
|
||
|
|
// would have been NewSize and because the NewRatio calculation could
|
||
|
|
// yield a size that is too small) and bound it by MaxNewSize above.
|
||
|
|
// This is not always best. The NewSize calculated by CMS (which has
|
||
|
|
// a fixed minimum of 16m) can sometimes be "too" large. Consider
|
||
|
|
// the case where -Xmx32m. The CMS calculated NewSize would be about
|
||
|
|
// half the entire heap which seems too large. But the counter
|
||
|
|
// example is seen when the client defaults for NewRatio are used.
|
||
|
|
// An initial young generation size of 640k was observed
|
||
|
|
// with -Xmx128m -XX:MaxNewSize=32m when NewSize was not used
|
||
|
|
// as a lower bound as with
|
||
|
|
// _min_gen0_size = MIN2(_min_gen0_size, MaxNewSize);
|
||
|
|
// and 640k seemed too small a young generation.
|
||
|
|
_min_gen0_size = MIN2(MAX2(_min_gen0_size, NewSize), MaxNewSize);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Parameters are valid, compute area sizes.
|
||
|
|
size_t max_new_size = align_size_down(_max_heap_byte_size / (NewRatio+1),
|
||
|
|
min_alignment());
|
||
|
|
max_new_size = MIN2(MAX2(max_new_size, _min_gen0_size), MaxNewSize);
|
||
|
|
|
||
|
|
// desired_new_size is used to set the initial size. The
|
||
|
|
// initial size must be greater than the minimum size.
|
||
|
|
size_t desired_new_size =
|
||
|
|
align_size_down(_initial_heap_byte_size / (NewRatio+1),
|
||
|
|
min_alignment());
|
||
|
|
|
||
|
|
size_t new_size = MIN2(MAX2(desired_new_size, _min_gen0_size), max_new_size);
|
||
|
|
|
||
|
|
_initial_gen0_size = new_size;
|
||
|
|
_max_gen0_size = max_new_size;
|
||
|
|
}
|
||
|
|
|
||
|
|
void TwoGenerationCollectorPolicy::initialize_size_info() {
|
||
|
|
GenCollectorPolicy::initialize_size_info();
|
||
|
|
|
||
|
|
// Minimum sizes of the generations may be different than
|
||
|
|
// the initial sizes. An inconsistently is permitted here
|
||
|
|
// in the total size that can be specified explicitly by
|
||
|
|
// command line specification of OldSize and NewSize and
|
||
|
|
// also a command line specification of -Xms. Issue a warning
|
||
|
|
// but allow the values to pass.
|
||
|
|
if (!FLAG_IS_DEFAULT(OldSize)) {
|
||
|
|
_min_gen1_size = OldSize;
|
||
|
|
// The generation minimums and the overall heap mimimum should
|
||
|
|
// be within one heap alignment.
|
||
|
|
if ((_min_gen1_size + _min_gen0_size + max_alignment()) <
|
||
|
|
_min_heap_byte_size) {
|
||
|
|
warning("Inconsistency between minimum heap size and minimum "
|
||
|
|
"generation sizes: using min heap = " SIZE_FORMAT,
|
||
|
|
_min_heap_byte_size);
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
_min_gen1_size = _min_heap_byte_size - _min_gen0_size;
|
||
|
|
}
|
||
|
|
|
||
|
|
_initial_gen1_size = _initial_heap_byte_size - _initial_gen0_size;
|
||
|
|
_max_gen1_size = _max_heap_byte_size - _max_gen0_size;
|
||
|
|
}
|
||
|
|
|
||
|
|
HeapWord* GenCollectorPolicy::mem_allocate_work(size_t size,
|
||
|
|
bool is_tlab,
|
||
|
|
bool* gc_overhead_limit_was_exceeded) {
|
||
|
|
GenCollectedHeap *gch = GenCollectedHeap::heap();
|
||
|
|
|
||
|
|
debug_only(gch->check_for_valid_allocation_state());
|
||
|
|
assert(gch->no_gc_in_progress(), "Allocation during gc not allowed");
|
||
|
|
HeapWord* result = NULL;
|
||
|
|
|
||
|
|
// Loop until the allocation is satisified,
|
||
|
|
// or unsatisfied after GC.
|
||
|
|
for (int try_count = 1; /* return or throw */; try_count += 1) {
|
||
|
|
HandleMark hm; // discard any handles allocated in each iteration
|
||
|
|
|
||
|
|
// First allocation attempt is lock-free.
|
||
|
|
Generation *gen0 = gch->get_gen(0);
|
||
|
|
assert(gen0->supports_inline_contig_alloc(),
|
||
|
|
"Otherwise, must do alloc within heap lock");
|
||
|
|
if (gen0->should_allocate(size, is_tlab)) {
|
||
|
|
result = gen0->par_allocate(size, is_tlab);
|
||
|
|
if (result != NULL) {
|
||
|
|
assert(gch->is_in_reserved(result), "result not in heap");
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
unsigned int gc_count_before; // read inside the Heap_lock locked region
|
||
|
|
{
|
||
|
|
MutexLocker ml(Heap_lock);
|
||
|
|
if (PrintGC && Verbose) {
|
||
|
|
gclog_or_tty->print_cr("TwoGenerationCollectorPolicy::mem_allocate_work:"
|
||
|
|
" attempting locked slow path allocation");
|
||
|
|
}
|
||
|
|
// Note that only large objects get a shot at being
|
||
|
|
// allocated in later generations.
|
||
|
|
bool first_only = ! should_try_older_generation_allocation(size);
|
||
|
|
|
||
|
|
result = gch->attempt_allocation(size, is_tlab, first_only);
|
||
|
|
if (result != NULL) {
|
||
|
|
assert(gch->is_in_reserved(result), "result not in heap");
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
// There are NULL's returned for different circumstances below.
|
||
|
|
// In general gc_overhead_limit_was_exceeded should be false so
|
||
|
|
// set it so here and reset it to true only if the gc time
|
||
|
|
// limit is being exceeded as checked below.
|
||
|
|
*gc_overhead_limit_was_exceeded = false;
|
||
|
|
|
||
|
|
if (GC_locker::is_active_and_needs_gc()) {
|
||
|
|
if (is_tlab) {
|
||
|
|
return NULL; // Caller will retry allocating individual object
|
||
|
|
}
|
||
|
|
if (!gch->is_maximal_no_gc()) {
|
||
|
|
// Try and expand heap to satisfy request
|
||
|
|
result = expand_heap_and_allocate(size, is_tlab);
|
||
|
|
// result could be null if we are out of space
|
||
|
|
if (result != NULL) {
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// 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);
|
||
|
|
// Wait for JNI critical section to be exited
|
||
|
|
GC_locker::stall_until_clear();
|
||
|
|
continue;
|
||
|
|
} else {
|
||
|
|
if (CheckJNICalls) {
|
||
|
|
fatal("Possible deadlock due to allocating while"
|
||
|
|
" in jni critical section");
|
||
|
|
}
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Read the gc count while the heap lock is held.
|
||
|
|
gc_count_before = Universe::heap()->total_collections();
|
||
|
|
}
|
||
|
|
|
||
|
|
// Allocation has failed and a collection is about
|
||
|
|
// to be done. If the gc time limit was exceeded the
|
||
|
|
// last time a collection was done, return NULL so
|
||
|
|
// that an out-of-memory will be thrown. Clear
|
||
|
|
// gc_time_limit_exceeded so that subsequent attempts
|
||
|
|
// at a collection will be made.
|
||
|
|
if (size_policy()->gc_time_limit_exceeded()) {
|
||
|
|
*gc_overhead_limit_was_exceeded = true;
|
||
|
|
size_policy()->set_gc_time_limit_exceeded(false);
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
VM_GenCollectForAllocation op(size,
|
||
|
|
is_tlab,
|
||
|
|
gc_count_before);
|
||
|
|
VMThread::execute(&op);
|
||
|
|
if (op.prologue_succeeded()) {
|
||
|
|
result = op.result();
|
||
|
|
if (op.gc_locked()) {
|
||
|
|
assert(result == NULL, "must be NULL if gc_locked() is true");
|
||
|
|
continue; // retry and/or stall as necessary
|
||
|
|
}
|
||
|
|
assert(result == NULL || gch->is_in_reserved(result),
|
||
|
|
"result not in heap");
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Give a warning if we seem to be looping forever.
|
||
|
|
if ((QueuedAllocationWarningCount > 0) &&
|
||
|
|
(try_count % QueuedAllocationWarningCount == 0)) {
|
||
|
|
warning("TwoGenerationCollectorPolicy::mem_allocate_work retries %d times \n\t"
|
||
|
|
" size=%d %s", try_count, size, is_tlab ? "(TLAB)" : "");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
HeapWord* GenCollectorPolicy::expand_heap_and_allocate(size_t size,
|
||
|
|
bool is_tlab) {
|
||
|
|
GenCollectedHeap *gch = GenCollectedHeap::heap();
|
||
|
|
HeapWord* result = NULL;
|
||
|
|
for (int i = number_of_generations() - 1; i >= 0 && result == NULL; i--) {
|
||
|
|
Generation *gen = gch->get_gen(i);
|
||
|
|
if (gen->should_allocate(size, is_tlab)) {
|
||
|
|
result = gen->expand_and_allocate(size, is_tlab);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
assert(result == NULL || gch->is_in_reserved(result), "result not in heap");
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
HeapWord* GenCollectorPolicy::satisfy_failed_allocation(size_t size,
|
||
|
|
bool is_tlab) {
|
||
|
|
GenCollectedHeap *gch = GenCollectedHeap::heap();
|
||
|
|
GCCauseSetter x(gch, GCCause::_allocation_failure);
|
||
|
|
HeapWord* result = NULL;
|
||
|
|
|
||
|
|
assert(size != 0, "Precondition violated");
|
||
|
|
if (GC_locker::is_active_and_needs_gc()) {
|
||
|
|
// GC locker is active; instead of a collection we will attempt
|
||
|
|
// to expand the heap, if there's room for expansion.
|
||
|
|
if (!gch->is_maximal_no_gc()) {
|
||
|
|
result = expand_heap_and_allocate(size, is_tlab);
|
||
|
|
}
|
||
|
|
return result; // could be null if we are out of space
|
||
|
|
} else if (!gch->incremental_collection_will_fail()) {
|
||
|
|
// The gc_prologues have not executed yet. The value
|
||
|
|
// for incremental_collection_will_fail() is the remanent
|
||
|
|
// of the last collection.
|
||
|
|
// Do an incremental collection.
|
||
|
|
gch->do_collection(false /* full */,
|
||
|
|
false /* clear_all_soft_refs */,
|
||
|
|
size /* size */,
|
||
|
|
is_tlab /* is_tlab */,
|
||
|
|
number_of_generations() - 1 /* max_level */);
|
||
|
|
} else {
|
||
|
|
// Try a full collection; see delta for bug id 6266275
|
||
|
|
// for the original code and why this has been simplified
|
||
|
|
// with from-space allocation criteria modified and
|
||
|
|
// such allocation moved out of the safepoint path.
|
||
|
|
gch->do_collection(true /* full */,
|
||
|
|
false /* clear_all_soft_refs */,
|
||
|
|
size /* size */,
|
||
|
|
is_tlab /* is_tlab */,
|
||
|
|
number_of_generations() - 1 /* max_level */);
|
||
|
|
}
|
||
|
|
|
||
|
|
result = gch->attempt_allocation(size, is_tlab, false /*first_only*/);
|
||
|
|
|
||
|
|
if (result != NULL) {
|
||
|
|
assert(gch->is_in_reserved(result), "result not in heap");
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
// OK, collection failed, try expansion.
|
||
|
|
result = expand_heap_and_allocate(size, is_tlab);
|
||
|
|
if (result != NULL) {
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
// If we reach this point, we're really out of memory. Try every trick
|
||
|
|
// we can to reclaim memory. Force collection of soft references. Force
|
||
|
|
// a complete compaction of the heap. Any additional methods for finding
|
||
|
|
// free memory should be here, especially if they are expensive. If this
|
||
|
|
// attempt fails, an OOM exception will be thrown.
|
||
|
|
{
|
||
|
|
IntFlagSetting flag_change(MarkSweepAlwaysCompactCount, 1); // Make sure the heap is fully compacted
|
||
|
|
|
||
|
|
gch->do_collection(true /* full */,
|
||
|
|
true /* clear_all_soft_refs */,
|
||
|
|
size /* size */,
|
||
|
|
is_tlab /* is_tlab */,
|
||
|
|
number_of_generations() - 1 /* max_level */);
|
||
|
|
}
|
||
|
|
|
||
|
|
result = gch->attempt_allocation(size, is_tlab, false /* first_only */);
|
||
|
|
if (result != NULL) {
|
||
|
|
assert(gch->is_in_reserved(result), "result not in heap");
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
// What else? We might try synchronous finalization later. If the total
|
||
|
|
// space available is large enough for the allocation, then a more
|
||
|
|
// complete compaction phase than we've tried so far might be
|
||
|
|
// appropriate.
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
size_t GenCollectorPolicy::large_typearray_limit() {
|
||
|
|
return FastAllocateSizeLimit;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Return true if any of the following is true:
|
||
|
|
// . the allocation won't fit into the current young gen heap
|
||
|
|
// . gc locker is occupied (jni critical section)
|
||
|
|
// . heap memory is tight -- the most recent previous collection
|
||
|
|
// was a full collection because a partial collection (would
|
||
|
|
// have) failed and is likely to fail again
|
||
|
|
bool GenCollectorPolicy::should_try_older_generation_allocation(
|
||
|
|
size_t word_size) const {
|
||
|
|
GenCollectedHeap* gch = GenCollectedHeap::heap();
|
||
|
|
size_t gen0_capacity = gch->get_gen(0)->capacity_before_gc();
|
||
|
|
return (word_size > heap_word_size(gen0_capacity))
|
||
|
|
|| (GC_locker::is_active_and_needs_gc())
|
||
|
|
|| ( gch->last_incremental_collection_failed()
|
||
|
|
&& gch->incremental_collection_will_fail());
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
//
|
||
|
|
// MarkSweepPolicy methods
|
||
|
|
//
|
||
|
|
|
||
|
|
MarkSweepPolicy::MarkSweepPolicy() {
|
||
|
|
initialize_all();
|
||
|
|
}
|
||
|
|
|
||
|
|
void MarkSweepPolicy::initialize_generations() {
|
||
|
|
initialize_perm_generation(PermGen::MarkSweepCompact);
|
||
|
|
_generations = new GenerationSpecPtr[number_of_generations()];
|
||
|
|
if (_generations == NULL)
|
||
|
|
vm_exit_during_initialization("Unable to allocate gen spec");
|
||
|
|
|
||
|
|
if (UseParNewGC && ParallelGCThreads > 0) {
|
||
|
|
_generations[0] = new GenerationSpec(Generation::ParNew, _initial_gen0_size, _max_gen0_size);
|
||
|
|
} else {
|
||
|
|
_generations[0] = new GenerationSpec(Generation::DefNew, _initial_gen0_size, _max_gen0_size);
|
||
|
|
}
|
||
|
|
_generations[1] = new GenerationSpec(Generation::MarkSweepCompact, _initial_gen1_size, _max_gen1_size);
|
||
|
|
|
||
|
|
if (_generations[0] == NULL || _generations[1] == NULL)
|
||
|
|
vm_exit_during_initialization("Unable to allocate gen spec");
|
||
|
|
}
|
||
|
|
|
||
|
|
void MarkSweepPolicy::initialize_gc_policy_counters() {
|
||
|
|
// initialize the policy counters - 2 collectors, 3 generations
|
||
|
|
if (UseParNewGC && ParallelGCThreads > 0) {
|
||
|
|
_gc_policy_counters = new GCPolicyCounters("ParNew:MSC", 2, 3);
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
_gc_policy_counters = new GCPolicyCounters("Copy:MSC", 2, 3);
|
||
|
|
}
|
||
|
|
}
|