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8008966: NPG: Inefficient Metaspace counter functions cause large young GC regressions

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Reviewed-by: mgerdin, coleenp
This commit is contained in:
Jon Masamitsu 2013-02-12 14:15:45 -08:00
parent eafc00bc25
commit d72b516201
12 changed files with 398 additions and 175 deletions
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2
hotspot/src/share/vm/classfile/classLoaderData.cpp
View File

@ -672,6 +672,8 @@ bool ClassLoaderDataGraph::do_unloading(BoolObjectClosure* is_alive_closure) {
dead->unload();
data = data->next();
// Remove from loader list.
// This class loader data will no longer be found
// in the ClassLoaderDataGraph.
if (prev != NULL) {
prev->set_next(data);
} else {

3
hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp
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@ -1304,7 +1304,7 @@ bool G1CollectedHeap::do_collection(bool explicit_gc,
print_heap_before_gc();
size_t metadata_prev_used = MetaspaceAux::used_in_bytes();
size_t metadata_prev_used = MetaspaceAux::allocated_used_bytes();
HRSPhaseSetter x(HRSPhaseFullGC);
verify_region_sets_optional();
@ -1425,6 +1425,7 @@ bool G1CollectedHeap::do_collection(bool explicit_gc,
// Delete metaspaces for unloaded class loaders and clean up loader_data graph
ClassLoaderDataGraph::purge();
MetaspaceAux::verify_metrics();
// Note: since we've just done a full GC, concurrent
// marking is no longer active. Therefore we need not

3
hotspot/src/share/vm/gc_implementation/parallelScavenge/psMarkSweep.cpp
View File

@ -177,7 +177,7 @@ bool PSMarkSweep::invoke_no_policy(bool clear_all_softrefs) {
size_t prev_used = heap->used();
// Capture metadata size before collection for sizing.
size_t metadata_prev_used = MetaspaceAux::used_in_bytes();
size_t metadata_prev_used = MetaspaceAux::allocated_used_bytes();
// For PrintGCDetails
size_t old_gen_prev_used = old_gen->used_in_bytes();
@ -238,6 +238,7 @@ bool PSMarkSweep::invoke_no_policy(bool clear_all_softrefs) {
// Delete metaspaces for unloaded class loaders and clean up loader_data graph
ClassLoaderDataGraph::purge();
MetaspaceAux::verify_metrics();
BiasedLocking::restore_marks();
Threads::gc_epilogue();

3
hotspot/src/share/vm/gc_implementation/parallelScavenge/psParallelCompact.cpp
View File

@ -891,7 +891,7 @@ public:
_heap_used = heap->used();
_young_gen_used = heap->young_gen()->used_in_bytes();
_old_gen_used = heap->old_gen()->used_in_bytes();
_metadata_used = MetaspaceAux::used_in_bytes();
_metadata_used = MetaspaceAux::allocated_used_bytes();
};
size_t heap_used() const { return _heap_used; }
@ -1026,6 +1026,7 @@ void PSParallelCompact::post_compact()
// Delete metaspaces for unloaded class loaders and clean up loader_data graph
ClassLoaderDataGraph::purge();
MetaspaceAux::verify_metrics();
Threads::gc_epilogue();
CodeCache::gc_epilogue();

5
hotspot/src/share/vm/gc_implementation/shared/vmGCOperations.cpp
View File

@ -225,7 +225,10 @@ void VM_CollectForMetadataAllocation::doit() {
gclog_or_tty->print_cr("\nCMS full GC for Metaspace");
}
heap->collect_as_vm_thread(GCCause::_metadata_GC_threshold);
_result = _loader_data->metaspace_non_null()->allocate(_size, _mdtype);
// After a GC try to allocate without expanding. Could fail
// and expansion will be tried below.
_result =
_loader_data->metaspace_non_null()->allocate(_size, _mdtype);
}
if (_result == NULL && !UseConcMarkSweepGC /* CMS already tried */) {
// If still failing, allow the Metaspace to expand.

4
hotspot/src/share/vm/memory/filemap.cpp
View File

@ -238,8 +238,8 @@ void FileMapInfo::write_header() {
void FileMapInfo::write_space(int i, Metaspace* space, bool read_only) {
align_file_position();
size_t used = space->used_words(Metaspace::NonClassType) * BytesPerWord;
size_t capacity = space->capacity_words(Metaspace::NonClassType) * BytesPerWord;
size_t used = space->used_bytes_slow(Metaspace::NonClassType);
size_t capacity = space->capacity_bytes_slow(Metaspace::NonClassType);
struct FileMapInfo::FileMapHeader::space_info* si = &_header._space[i];
write_region(i, (char*)space->bottom(), used, capacity, read_only, false);
}

3
hotspot/src/share/vm/memory/genCollectedHeap.cpp
View File

@ -377,7 +377,7 @@ void GenCollectedHeap::do_collection(bool full,
ClearedAllSoftRefs casr(do_clear_all_soft_refs, collector_policy());
const size_t metadata_prev_used = MetaspaceAux::used_in_bytes();
const size_t metadata_prev_used = MetaspaceAux::allocated_used_bytes();
print_heap_before_gc();
@ -556,6 +556,7 @@ void GenCollectedHeap::do_collection(bool full,
if (complete) {
// Delete metaspaces for unloaded class loaders and clean up loader_data graph
ClassLoaderDataGraph::purge();
MetaspaceAux::verify_metrics();
// Resize the metaspace capacity after full collections
MetaspaceGC::compute_new_size();
update_full_collections_completed();

392
hotspot/src/share/vm/memory/metaspace.cpp
View File

@ -47,7 +47,6 @@ typedef BinaryTreeDictionary<Metachunk, FreeList> ChunkTreeDictionary;
// the free chunk lists
const bool metaspace_slow_verify = false;
// Parameters for stress mode testing
const uint metadata_deallocate_a_lot_block = 10;
const uint metadata_deallocate_a_lock_chunk = 3;
@ -220,7 +219,6 @@ class ChunkManager VALUE_OBJ_CLASS_SPEC {
void print_on(outputStream* st);
};
// Used to manage the free list of Metablocks (a block corresponds
// to the allocation of a quantum of metadata).
class BlockFreelist VALUE_OBJ_CLASS_SPEC {
@ -298,7 +296,7 @@ class VirtualSpaceNode : public CHeapObj<mtClass> {
MemRegion* reserved() { return &_reserved; }
VirtualSpace* virtual_space() const { return (VirtualSpace*) &_virtual_space; }
// Returns true if "word_size" is available in the virtual space
// Returns true if "word_size" is available in the VirtualSpace
bool is_available(size_t word_size) { return _top + word_size <= end(); }
MetaWord* top() const { return _top; }
@ -313,6 +311,7 @@ class VirtualSpaceNode : public CHeapObj<mtClass> {
// used and capacity in this single entry in the list
size_t used_words_in_vs() const;
size_t capacity_words_in_vs() const;
size_t free_words_in_vs() const;
bool initialize();
@ -449,6 +448,8 @@ class VirtualSpaceList : public CHeapObj<mtClass> {
VirtualSpaceList(size_t word_size);
VirtualSpaceList(ReservedSpace rs);
size_t free_bytes();
Metachunk* get_new_chunk(size_t word_size,
size_t grow_chunks_by_words,
size_t medium_chunk_bunch);
@ -579,7 +580,11 @@ class SpaceManager : public CHeapObj<mtClass> {
bool has_small_chunk_limit() { return !vs_list()->is_class(); }
// Sum of all space in allocated chunks
size_t _allocation_total;
size_t _allocated_blocks_words;
// Sum of all allocated chunks
size_t _allocated_chunks_words;
size_t _allocated_chunks_count;
// Free lists of blocks are per SpaceManager since they
// are assumed to be in chunks in use by the SpaceManager
@ -635,12 +640,27 @@ class SpaceManager : public CHeapObj<mtClass> {
size_t medium_chunk_size() { return (size_t) vs_list()->is_class() ? ClassMediumChunk : MediumChunk; }
size_t medium_chunk_bunch() { return medium_chunk_size() * MediumChunkMultiple; }
size_t allocation_total() const { return _allocation_total; }
void inc_allocation_total(size_t v) { Atomic::add_ptr(v, &_allocation_total); }
size_t allocated_blocks_words() const { return _allocated_blocks_words; }
size_t allocated_blocks_bytes() const { return _allocated_blocks_words * BytesPerWord; }
size_t allocated_chunks_words() const { return _allocated_chunks_words; }
size_t allocated_chunks_count() const { return _allocated_chunks_count; }
bool is_humongous(size_t word_size) { return word_size > medium_chunk_size(); }
static Mutex* expand_lock() { return _expand_lock; }
// Increment the per Metaspace and global running sums for Metachunks
// by the given size. This is used when a Metachunk to added to
// the in-use list.
void inc_size_metrics(size_t words);
// Increment the per Metaspace and global running sums Metablocks by the given
// size. This is used when a Metablock is allocated.
void inc_used_metrics(size_t words);
// Delete the portion of the running sums for this SpaceManager. That is,
// the globals running sums for the Metachunks and Metablocks are
// decremented for all the Metachunks in-use by this SpaceManager.
void dec_total_from_size_metrics();
// Set the sizes for the initial chunks.
void get_initial_chunk_sizes(Metaspace::MetaspaceType type,
size_t* chunk_word_size,
@ -686,7 +706,7 @@ class SpaceManager : public CHeapObj<mtClass> {
void verify_chunk_size(Metachunk* chunk);
NOT_PRODUCT(void mangle_freed_chunks();)
#ifdef ASSERT
void verify_allocation_total();
void verify_allocated_blocks_words();
#endif
};
@ -797,6 +817,9 @@ size_t VirtualSpaceNode::capacity_words_in_vs() const {
return pointer_delta(end(), bottom(), sizeof(MetaWord));
}
size_t VirtualSpaceNode::free_words_in_vs() const {
return pointer_delta(end(), top(), sizeof(MetaWord));
}
// Allocates the chunk from the virtual space only.
// This interface is also used internally for debugging. Not all
@ -1071,6 +1094,10 @@ VirtualSpaceList::VirtualSpaceList(ReservedSpace rs) :
link_vs(class_entry, rs.size()/BytesPerWord);
}
size_t VirtualSpaceList::free_bytes() {
return virtual_space_list()->free_words_in_vs() * BytesPerWord;
}
// Allocate another meta virtual space and add it to the list.
bool VirtualSpaceList::grow_vs(size_t vs_word_size) {
assert_lock_strong(SpaceManager::expand_lock());
@ -1211,9 +1238,9 @@ bool VirtualSpaceList::contains(const void *ptr) {
//
// After the GC the compute_new_size() for MetaspaceGC is called to
// resize the capacity of the metaspaces. The current implementation
// is based on the flags MinMetaspaceFreeRatio and MaxHeapFreeRatio used
// is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
// to resize the Java heap by some GC's. New flags can be implemented
// if really needed. MinHeapFreeRatio is used to calculate how much
// if really needed. MinMetaspaceFreeRatio is used to calculate how much
// free space is desirable in the metaspace capacity to decide how much
// to increase the HWM. MaxMetaspaceFreeRatio is used to decide how much
// free space is desirable in the metaspace capacity before decreasing
@ -1248,7 +1275,11 @@ size_t MetaspaceGC::delta_capacity_until_GC(size_t word_size) {
}
bool MetaspaceGC::should_expand(VirtualSpaceList* vsl, size_t word_size) {
size_t committed_capacity_bytes = MetaspaceAux::allocated_capacity_bytes();
// If the user wants a limit, impose one.
size_t max_metaspace_size_bytes = MaxMetaspaceSize;
size_t metaspace_size_bytes = MetaspaceSize;
if (!FLAG_IS_DEFAULT(MaxMetaspaceSize) &&
MetaspaceAux::reserved_in_bytes() >= MaxMetaspaceSize) {
return false;
@ -1260,57 +1291,48 @@ bool MetaspaceGC::should_expand(VirtualSpaceList* vsl, size_t word_size) {
// If this is part of an allocation after a GC, expand
// unconditionally.
if(MetaspaceGC::expand_after_GC()) {
if (MetaspaceGC::expand_after_GC()) {
return true;
}
size_t metaspace_size_words = MetaspaceSize / BytesPerWord;
// If the capacity is below the minimum capacity, allow the
// expansion. Also set the high-water-mark (capacity_until_GC)
// to that minimum capacity so that a GC will not be induced
// until that minimum capacity is exceeded.
if (vsl->capacity_words_sum() < metaspace_size_words ||
if (committed_capacity_bytes < metaspace_size_bytes ||
capacity_until_GC() == 0) {
set_capacity_until_GC(metaspace_size_words);
set_capacity_until_GC(metaspace_size_bytes);
return true;
} else {
if (vsl->capacity_words_sum() < capacity_until_GC()) {
if (committed_capacity_bytes < capacity_until_GC()) {
return true;
} else {
if (TraceMetadataChunkAllocation && Verbose) {
gclog_or_tty->print_cr(" allocation request size " SIZE_FORMAT
" capacity_until_GC " SIZE_FORMAT
" capacity_words_sum " SIZE_FORMAT
" used_words_sum " SIZE_FORMAT
" free chunks " SIZE_FORMAT
" free chunks count %d",
" allocated_capacity_bytes " SIZE_FORMAT,
word_size,
capacity_until_GC(),
vsl->capacity_words_sum(),
vsl->used_words_sum(),
vsl->chunk_manager()->free_chunks_total(),
vsl->chunk_manager()->free_chunks_count());
MetaspaceAux::allocated_capacity_bytes());
}
return false;
}
}
}
// Variables are in bytes
void MetaspaceGC::compute_new_size() {
assert(_shrink_factor <= 100, "invalid shrink factor");
uint current_shrink_factor = _shrink_factor;
_shrink_factor = 0;
VirtualSpaceList *vsl = Metaspace::space_list();
size_t capacity_after_gc = vsl->capacity_bytes_sum();
// Check to see if these two can be calculated without walking the CLDG
size_t used_after_gc = vsl->used_bytes_sum();
size_t capacity_until_GC = vsl->capacity_bytes_sum();
size_t free_after_gc = capacity_until_GC - used_after_gc;
// Until a faster way of calculating the "used" quantity is implemented,
// use "capacity".
const size_t used_after_gc = MetaspaceAux::allocated_capacity_bytes();
const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
const double maximum_used_percentage = 1.0 - minimum_free_percentage;
@ -1323,45 +1345,34 @@ void MetaspaceGC::compute_new_size() {
MetaspaceSize);
if (PrintGCDetails && Verbose) {
const double free_percentage = ((double)free_after_gc) / capacity_until_GC;
gclog_or_tty->print_cr("\nMetaspaceGC::compute_new_size: ");
gclog_or_tty->print_cr(" "
" minimum_free_percentage: %6.2f"
" maximum_used_percentage: %6.2f",
minimum_free_percentage,
maximum_used_percentage);
double d_free_after_gc = free_after_gc / (double) K;
gclog_or_tty->print_cr(" "
" free_after_gc : %6.1fK"
" used_after_gc : %6.1fK"
" capacity_after_gc : %6.1fK"
" metaspace HWM : %6.1fK",
free_after_gc / (double) K,
used_after_gc / (double) K,
capacity_after_gc / (double) K,
capacity_until_GC / (double) K);
gclog_or_tty->print_cr(" "
" free_percentage: %6.2f",
free_percentage);
" used_after_gc : %6.1fKB",
used_after_gc / (double) K);
}
size_t shrink_bytes = 0;
if (capacity_until_GC < minimum_desired_capacity) {
// If we have less capacity below the metaspace HWM, then
// increment the HWM.
size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
// Don't expand unless it's significant
if (expand_bytes >= MinMetaspaceExpansion) {
size_t expand_words = expand_bytes / BytesPerWord;
MetaspaceGC::inc_capacity_until_GC(expand_words);
MetaspaceGC::set_capacity_until_GC(capacity_until_GC + expand_bytes);
}
if (PrintGCDetails && Verbose) {
size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes();
size_t new_capacity_until_GC = capacity_until_GC;
gclog_or_tty->print_cr(" expanding:"
" minimum_desired_capacity: %6.1fK"
" expand_words: %6.1fK"
" MinMetaspaceExpansion: %6.1fK"
" new metaspace HWM: %6.1fK",
" minimum_desired_capacity: %6.1fKB"
" expand_bytes: %6.1fKB"
" MinMetaspaceExpansion: %6.1fKB"
" new metaspace HWM: %6.1fKB",
minimum_desired_capacity / (double) K,
expand_bytes / (double) K,
MinMetaspaceExpansion / (double) K,
@ -1371,11 +1382,10 @@ void MetaspaceGC::compute_new_size() {
}
// No expansion, now see if we want to shrink
size_t shrink_words = 0;
// We would never want to shrink more than this
size_t max_shrink_words = capacity_until_GC - minimum_desired_capacity;
assert(max_shrink_words >= 0, err_msg("max_shrink_words " SIZE_FORMAT,
max_shrink_words));
size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
assert(max_shrink_bytes >= 0, err_msg("max_shrink_bytes " SIZE_FORMAT,
max_shrink_bytes));
// Should shrinking be considered?
if (MaxMetaspaceFreeRatio < 100) {
@ -1385,17 +1395,15 @@ void MetaspaceGC::compute_new_size() {
size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(max_uintx));
maximum_desired_capacity = MAX2(maximum_desired_capacity,
MetaspaceSize);
if (PrintGC && Verbose) {
if (PrintGCDetails && Verbose) {
gclog_or_tty->print_cr(" "
" maximum_free_percentage: %6.2f"
" minimum_used_percentage: %6.2f",
maximum_free_percentage,
minimum_used_percentage);
gclog_or_tty->print_cr(" "
" capacity_until_GC: %6.1fK"
" minimum_desired_capacity: %6.1fK"
" maximum_desired_capacity: %6.1fK",
capacity_until_GC / (double) K,
" minimum_desired_capacity: %6.1fKB"
" maximum_desired_capacity: %6.1fKB",
minimum_desired_capacity / (double) K,
maximum_desired_capacity / (double) K);
}
@ -1405,17 +1413,17 @@ void MetaspaceGC::compute_new_size() {
if (capacity_until_GC > maximum_desired_capacity) {
// Capacity too large, compute shrinking size
shrink_words = capacity_until_GC - maximum_desired_capacity;
shrink_bytes = capacity_until_GC - maximum_desired_capacity;
// We don't want shrink all the way back to initSize if people call
// System.gc(), because some programs do that between "phases" and then
// we'd just have to grow the heap up again for the next phase. So we
// damp the shrinking: 0% on the first call, 10% on the second call, 40%
// on the third call, and 100% by the fourth call. But if we recompute
// size without shrinking, it goes back to 0%.
shrink_words = shrink_words / 100 * current_shrink_factor;
assert(shrink_words <= max_shrink_words,
shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
assert(shrink_bytes <= max_shrink_bytes,
err_msg("invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
shrink_words, max_shrink_words));
shrink_bytes, max_shrink_bytes));
if (current_shrink_factor == 0) {
_shrink_factor = 10;
} else {
@ -1429,11 +1437,11 @@ void MetaspaceGC::compute_new_size() {
MetaspaceSize / (double) K,
maximum_desired_capacity / (double) K);
gclog_or_tty->print_cr(" "
" shrink_words: %.1fK"
" shrink_bytes: %.1fK"
" current_shrink_factor: %d"
" new shrink factor: %d"
" MinMetaspaceExpansion: %.1fK",
shrink_words / (double) K,
shrink_bytes / (double) K,
current_shrink_factor,
_shrink_factor,
MinMetaspaceExpansion / (double) K);
@ -1441,23 +1449,11 @@ void MetaspaceGC::compute_new_size() {
}
}
// Don't shrink unless it's significant
if (shrink_words >= MinMetaspaceExpansion) {
VirtualSpaceNode* csp = vsl->current_virtual_space();
size_t available_to_shrink = csp->capacity_words_in_vs() -
csp->used_words_in_vs();
shrink_words = MIN2(shrink_words, available_to_shrink);
csp->shrink_by(shrink_words);
MetaspaceGC::dec_capacity_until_GC(shrink_words);
if (PrintGCDetails && Verbose) {
size_t new_capacity_until_GC = MetaspaceGC::capacity_until_GC_in_bytes();
gclog_or_tty->print_cr(" metaspace HWM: %.1fK", new_capacity_until_GC / (double) K);
if (shrink_bytes >= MinMetaspaceExpansion &&
((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
MetaspaceGC::set_capacity_until_GC(capacity_until_GC - shrink_bytes);
}
}
assert(used_after_gc <= vsl->capacity_bytes_sum(),
"sanity check");
}
// Metadebug methods
@ -1860,18 +1856,28 @@ size_t SpaceManager::sum_waste_in_chunks_in_use(ChunkIndex index) const {
}
size_t SpaceManager::sum_capacity_in_chunks_in_use() const {
// For CMS use "allocated_chunks_words()" which does not need the
// Metaspace lock. For the other collectors sum over the
// lists. Use both methods as a check that "allocated_chunks_words()"
// is correct. That is, sum_capacity_in_chunks() is too expensive
// to use in the product and allocated_chunks_words() should be used
// but allow for checking that allocated_chunks_words() returns the same
// value as sum_capacity_in_chunks_in_use() which is the definitive
// answer.
if (UseConcMarkSweepGC) {
return allocated_chunks_words();
} else {
MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
size_t sum = 0;
for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
Metachunk* chunk = chunks_in_use(i);
while (chunk != NULL) {
// Just changed this sum += chunk->capacity_word_size();
// sum += chunk->word_size() - Metachunk::overhead();
sum += chunk->capacity_word_size();
chunk = chunk->next();
}
}
return sum;
}
}
size_t SpaceManager::sum_count_in_chunks_in_use() {
@ -2029,12 +2035,44 @@ void SpaceManager::print_on(outputStream* st) const {
SpaceManager::SpaceManager(Mutex* lock,
VirtualSpaceList* vs_list) :
_vs_list(vs_list),
_allocation_total(0),
_allocated_blocks_words(0),
_allocated_chunks_words(0),
_allocated_chunks_count(0),
_lock(lock)
{
initialize();
}
void SpaceManager::inc_size_metrics(size_t words) {
assert_lock_strong(SpaceManager::expand_lock());
// Total of allocated Metachunks and allocated Metachunks count
// for each SpaceManager
_allocated_chunks_words = _allocated_chunks_words + words;
_allocated_chunks_count++;
// Global total of capacity in allocated Metachunks
MetaspaceAux::inc_capacity(words);
// Global total of allocated Metablocks.
// used_words_slow() includes the overhead in each
// Metachunk so include it in the used when the
// Metachunk is first added (so only added once per
// Metachunk).
MetaspaceAux::inc_used(Metachunk::overhead());
}
void SpaceManager::inc_used_metrics(size_t words) {
// Add to the per SpaceManager total
Atomic::add_ptr(words, &_allocated_blocks_words);
// Add to the global total
MetaspaceAux::inc_used(words);
}
void SpaceManager::dec_total_from_size_metrics() {
MetaspaceAux::dec_capacity(allocated_chunks_words());
MetaspaceAux::dec_used(allocated_blocks_words());
// Also deduct the overhead per Metachunk
MetaspaceAux::dec_used(allocated_chunks_count() * Metachunk::overhead());
}
void SpaceManager::initialize() {
Metadebug::init_allocation_fail_alot_count();
for (ChunkIndex i = ZeroIndex; i < NumberOfInUseLists; i = next_chunk_index(i)) {
@ -2073,7 +2111,10 @@ void ChunkManager::return_chunks(ChunkIndex index, Metachunk* chunks) {
SpaceManager::~SpaceManager() {
// This call this->_lock which can't be done while holding expand_lock()
const size_t in_use_before = sum_capacity_in_chunks_in_use();
assert(sum_capacity_in_chunks_in_use() == allocated_chunks_words(),
err_msg("sum_capacity_in_chunks_in_use() " SIZE_FORMAT
" allocated_chunks_words() " SIZE_FORMAT,
sum_capacity_in_chunks_in_use(), allocated_chunks_words()));
MutexLockerEx fcl(SpaceManager::expand_lock(),
Mutex::_no_safepoint_check_flag);
@ -2082,6 +2123,8 @@ SpaceManager::~SpaceManager() {
chunk_manager->slow_locked_verify();
dec_total_from_size_metrics();
if (TraceMetadataChunkAllocation && Verbose) {
gclog_or_tty->print_cr("~SpaceManager(): " PTR_FORMAT, this);
locked_print_chunks_in_use_on(gclog_or_tty);
@ -2092,7 +2135,7 @@ SpaceManager::~SpaceManager() {
// Have to update before the chunks_in_use lists are emptied
// below.
chunk_manager->inc_free_chunks_total(in_use_before,
chunk_manager->inc_free_chunks_total(allocated_chunks_words(),
sum_count_in_chunks_in_use());
// Add all the chunks in use by this space manager
@ -2158,7 +2201,6 @@ SpaceManager::~SpaceManager() {
chunk_manager->humongous_dictionary()->total_count(),
chunk_size_name(HumongousIndex));
}
set_chunks_in_use(HumongousIndex, NULL);
chunk_manager->slow_locked_verify();
}
@ -2238,13 +2280,18 @@ void SpaceManager::add_chunk(Metachunk* new_chunk, bool make_current) {
assert(new_chunk->word_size() > medium_chunk_size(), "List inconsistency");
}
// Add to the running sum of capacity
inc_size_metrics(new_chunk->word_size());
assert(new_chunk->is_empty(), "Not ready for reuse");
if (TraceMetadataChunkAllocation && Verbose) {
gclog_or_tty->print("SpaceManager::add_chunk: %d) ",
sum_count_in_chunks_in_use());
new_chunk->print_on(gclog_or_tty);
if (vs_list() != NULL) {
vs_list()->chunk_manager()->locked_print_free_chunks(tty);
}
}
}
Metachunk* SpaceManager::get_new_chunk(size_t word_size,
@ -2314,7 +2361,7 @@ MetaWord* SpaceManager::allocate_work(size_t word_size) {
// of memory if this returns null.
if (DumpSharedSpaces) {
assert(current_chunk() != NULL, "should never happen");
inc_allocation_total(word_size);
inc_used_metrics(word_size);
return current_chunk()->allocate(word_size); // caller handles null result
}
if (current_chunk() != NULL) {
@ -2325,7 +2372,7 @@ MetaWord* SpaceManager::allocate_work(size_t word_size) {
result = grow_and_allocate(word_size);
}
if (result > 0) {
inc_allocation_total(word_size);
inc_used_metrics(word_size);
assert(result != (MetaWord*) chunks_in_use(MediumIndex),
"Head of the list is being allocated");
}
@ -2359,20 +2406,14 @@ void SpaceManager::verify_chunk_size(Metachunk* chunk) {
}
#ifdef ASSERT
void SpaceManager::verify_allocation_total() {
void SpaceManager::verify_allocated_blocks_words() {
// Verification is only guaranteed at a safepoint.
if (SafepointSynchronize::is_at_safepoint()) {
gclog_or_tty->print_cr("Chunk " PTR_FORMAT " allocation_total " SIZE_FORMAT
" sum_used_in_chunks_in_use " SIZE_FORMAT,
this,
allocation_total(),
sum_used_in_chunks_in_use());
}
MutexLockerEx cl(lock(), Mutex::_no_safepoint_check_flag);
assert(allocation_total() == sum_used_in_chunks_in_use(),
assert(SafepointSynchronize::is_at_safepoint() || !Universe::is_fully_initialized(),
"Verification can fail if the applications is running");
assert(allocated_blocks_words() == sum_used_in_chunks_in_use(),
err_msg("allocation total is not consistent " SIZE_FORMAT
" vs " SIZE_FORMAT,
allocation_total(), sum_used_in_chunks_in_use()));
allocated_blocks_words(), sum_used_in_chunks_in_use()));
}
#endif
@ -2428,14 +2469,65 @@ void SpaceManager::mangle_freed_chunks() {
// MetaspaceAux
size_t MetaspaceAux::used_in_bytes(Metaspace::MetadataType mdtype) {
size_t MetaspaceAux::_allocated_capacity_words = 0;
size_t MetaspaceAux::_allocated_used_words = 0;
size_t MetaspaceAux::free_bytes() {
size_t result = 0;
if (Metaspace::class_space_list() != NULL) {
result = result + Metaspace::class_space_list()->free_bytes();
}
if (Metaspace::space_list() != NULL) {
result = result + Metaspace::space_list()->free_bytes();
}
return result;
}
void MetaspaceAux::dec_capacity(size_t words) {
assert_lock_strong(SpaceManager::expand_lock());
assert(words <= _allocated_capacity_words,
err_msg("About to decrement below 0: words " SIZE_FORMAT
" is greater than _allocated_capacity_words " SIZE_FORMAT,
words, _allocated_capacity_words));
_allocated_capacity_words = _allocated_capacity_words - words;
}
void MetaspaceAux::inc_capacity(size_t words) {
assert_lock_strong(SpaceManager::expand_lock());
// Needs to be atomic
_allocated_capacity_words = _allocated_capacity_words + words;
}
void MetaspaceAux::dec_used(size_t words) {
assert(words <= _allocated_used_words,
err_msg("About to decrement below 0: words " SIZE_FORMAT
" is greater than _allocated_used_words " SIZE_FORMAT,
words, _allocated_used_words));
// For CMS deallocation of the Metaspaces occurs during the
// sweep which is a concurrent phase. Protection by the expand_lock()
// is not enough since allocation is on a per Metaspace basis
// and protected by the Metaspace lock.
jlong minus_words = (jlong) - (jlong) words;
Atomic::add_ptr(minus_words, &_allocated_used_words);
}
void MetaspaceAux::inc_used(size_t words) {
// _allocated_used_words tracks allocations for
// each piece of metadata. Those allocations are
// generally done concurrently by different application
// threads so must be done atomically.
Atomic::add_ptr(words, &_allocated_used_words);
}
size_t MetaspaceAux::used_bytes_slow(Metaspace::MetadataType mdtype) {
size_t used = 0;
ClassLoaderDataGraphMetaspaceIterator iter;
while (iter.repeat()) {
Metaspace* msp = iter.get_next();
// Sum allocation_total for each metaspace
// Sum allocated_blocks_words for each metaspace
if (msp != NULL) {
used += msp->used_words(mdtype);
used += msp->used_words_slow(mdtype);
}
}
return used * BytesPerWord;
@ -2453,13 +2545,15 @@ size_t MetaspaceAux::free_in_bytes(Metaspace::MetadataType mdtype) {
return free * BytesPerWord;
}
size_t MetaspaceAux::capacity_in_bytes(Metaspace::MetadataType mdtype) {
size_t capacity = free_chunks_total(mdtype);
size_t MetaspaceAux::capacity_bytes_slow(Metaspace::MetadataType mdtype) {
// Don't count the space in the freelists. That space will be
// added to the capacity calculation as needed.
size_t capacity = 0;
ClassLoaderDataGraphMetaspaceIterator iter;
while (iter.repeat()) {
Metaspace* msp = iter.get_next();
if (msp != NULL) {
capacity += msp->capacity_words(mdtype);
capacity += msp->capacity_words_slow(mdtype);
}
}
return capacity * BytesPerWord;
@ -2486,23 +2580,30 @@ size_t MetaspaceAux::free_chunks_total_in_bytes(Metaspace::MetadataType mdtype)
return free_chunks_total(mdtype) * BytesPerWord;
}
size_t MetaspaceAux::free_chunks_total() {
return free_chunks_total(Metaspace::ClassType) +
free_chunks_total(Metaspace::NonClassType);
}
size_t MetaspaceAux::free_chunks_total_in_bytes() {
return free_chunks_total() * BytesPerWord;
}
void MetaspaceAux::print_metaspace_change(size_t prev_metadata_used) {
gclog_or_tty->print(", [Metaspace:");
if (PrintGCDetails && Verbose) {
gclog_or_tty->print(" " SIZE_FORMAT
"->" SIZE_FORMAT
"(" SIZE_FORMAT "/" SIZE_FORMAT ")",
"(" SIZE_FORMAT ")",
prev_metadata_used,
used_in_bytes(),
capacity_in_bytes(),
allocated_capacity_bytes(),
reserved_in_bytes());
} else {
gclog_or_tty->print(" " SIZE_FORMAT "K"
"->" SIZE_FORMAT "K"
"(" SIZE_FORMAT "K/" SIZE_FORMAT "K)",
"(" SIZE_FORMAT "K)",
prev_metadata_used / K,
used_in_bytes()/ K,
capacity_in_bytes()/K,
allocated_capacity_bytes() / K,
reserved_in_bytes()/ K);
}
@ -2517,23 +2618,30 @@ void MetaspaceAux::print_on(outputStream* out) {
out->print_cr(" Metaspace total "
SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
" reserved " SIZE_FORMAT "K",
capacity_in_bytes()/K, used_in_bytes()/K, reserved_in_bytes()/K);
allocated_capacity_bytes()/K, allocated_used_bytes()/K, reserved_in_bytes()/K);
#if 0
// The calls to capacity_bytes_slow() and used_bytes_slow() cause
// lock ordering assertion failures with some collectors. Do
// not include this code until the lock ordering is fixed.
if (PrintGCDetails && Verbose) {
out->print_cr(" data space "
SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
" reserved " SIZE_FORMAT "K",
capacity_in_bytes(nct)/K, used_in_bytes(nct)/K, reserved_in_bytes(nct)/K);
capacity_bytes_slow(nct)/K, used_bytes_slow(nct)/K, reserved_in_bytes(nct)/K);
out->print_cr(" class space "
SIZE_FORMAT "K, used " SIZE_FORMAT "K,"
" reserved " SIZE_FORMAT "K",
capacity_in_bytes(ct)/K, used_in_bytes(ct)/K, reserved_in_bytes(ct)/K);
capacity_bytes_slow(ct)/K, used_bytes_slow(ct)/K, reserved_in_bytes(ct)/K);
}
#endif
}
// Print information for class space and data space separately.
// This is almost the same as above.
void MetaspaceAux::print_on(outputStream* out, Metaspace::MetadataType mdtype) {
size_t free_chunks_capacity_bytes = free_chunks_total_in_bytes(mdtype);
size_t capacity_bytes = capacity_in_bytes(mdtype);
size_t used_bytes = used_in_bytes(mdtype);
size_t capacity_bytes = capacity_bytes_slow(mdtype);
size_t used_bytes = used_bytes_slow(mdtype);
size_t free_bytes = free_in_bytes(mdtype);
size_t used_and_free = used_bytes + free_bytes +
free_chunks_capacity_bytes;
@ -2606,6 +2714,36 @@ void MetaspaceAux::verify_free_chunks() {
Metaspace::class_space_list()->chunk_manager()->verify();
}
void MetaspaceAux::verify_capacity() {
#ifdef ASSERT
size_t running_sum_capacity_bytes = allocated_capacity_bytes();
// For purposes of the running sum of used, verify against capacity
size_t capacity_in_use_bytes = capacity_bytes_slow();
assert(running_sum_capacity_bytes == capacity_in_use_bytes,
err_msg("allocated_capacity_words() * BytesPerWord " SIZE_FORMAT
" capacity_bytes_slow()" SIZE_FORMAT,
running_sum_capacity_bytes, capacity_in_use_bytes));
#endif
}
void MetaspaceAux::verify_used() {
#ifdef ASSERT
size_t running_sum_used_bytes = allocated_used_bytes();
// For purposes of the running sum of used, verify against capacity
size_t used_in_use_bytes = used_bytes_slow();
assert(allocated_used_bytes() == used_in_use_bytes,
err_msg("allocated_used_bytes() " SIZE_FORMAT
" used_bytes_slow()()" SIZE_FORMAT,
allocated_used_bytes(), used_in_use_bytes));
#endif
}
void MetaspaceAux::verify_metrics() {
verify_capacity();
verify_used();
}
// Metaspace methods
size_t Metaspace::_first_chunk_word_size = 0;
@ -2755,8 +2893,8 @@ MetaWord* Metaspace::expand_and_allocate(size_t word_size, MetadataType mdtype)
MetaWord* result;
MetaspaceGC::set_expand_after_GC(true);
size_t before_inc = MetaspaceGC::capacity_until_GC();
size_t delta_words = MetaspaceGC::delta_capacity_until_GC(word_size);
MetaspaceGC::inc_capacity_until_GC(delta_words);
size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size) * BytesPerWord;
MetaspaceGC::inc_capacity_until_GC(delta_bytes);
if (PrintGCDetails && Verbose) {
gclog_or_tty->print_cr("Increase capacity to GC from " SIZE_FORMAT
" to " SIZE_FORMAT, before_inc, MetaspaceGC::capacity_until_GC());
@ -2774,8 +2912,8 @@ char* Metaspace::bottom() const {
return (char*)vsm()->current_chunk()->bottom();
}
size_t Metaspace::used_words(MetadataType mdtype) const {
// return vsm()->allocation_total();
size_t Metaspace::used_words_slow(MetadataType mdtype) const {
// return vsm()->allocated_used_words();
return mdtype == ClassType ? class_vsm()->sum_used_in_chunks_in_use() :
vsm()->sum_used_in_chunks_in_use(); // includes overhead!
}
@ -2790,11 +2928,19 @@ size_t Metaspace::free_words(MetadataType mdtype) const {
// have been made. Don't include space in the global freelist and
// in the space available in the dictionary which
// is already counted in some chunk.
size_t Metaspace::capacity_words(MetadataType mdtype) const {
size_t Metaspace::capacity_words_slow(MetadataType mdtype) const {
return mdtype == ClassType ? class_vsm()->sum_capacity_in_chunks_in_use() :
vsm()->sum_capacity_in_chunks_in_use();
}
size_t Metaspace::used_bytes_slow(MetadataType mdtype) const {
return used_words_slow(mdtype) * BytesPerWord;
}
size_t Metaspace::capacity_bytes_slow(MetadataType mdtype) const {
return capacity_words_slow(mdtype) * BytesPerWord;
}
void Metaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
if (SafepointSynchronize::is_at_safepoint()) {
assert(Thread::current()->is_VM_thread(), "should be the VM thread");
@ -2921,10 +3067,6 @@ void Metaspace::verify() {
}
void Metaspace::dump(outputStream* const out) const {
if (UseMallocOnly) {
// Just print usage for now
out->print_cr("usage %d", used_words(Metaspace::NonClassType));
}
out->print_cr("\nVirtual space manager: " INTPTR_FORMAT, vsm());
vsm()->dump(out);
out->print_cr("\nClass space manager: " INTPTR_FORMAT, class_vsm());

96
hotspot/src/share/vm/memory/metaspace.hpp
View File

@ -111,6 +111,10 @@ class Metaspace : public CHeapObj<mtClass> {
SpaceManager* _class_vsm;
SpaceManager* class_vsm() const { return _class_vsm; }
// Allocate space for metadata of type mdtype. This is space
// within a Metachunk and is used by
// allocate(ClassLoaderData*, size_t, bool, MetadataType, TRAPS)
// which returns a Metablock.
MetaWord* allocate(size_t word_size, MetadataType mdtype);
// Virtual Space lists for both classes and other metadata
@ -133,11 +137,14 @@ class Metaspace : public CHeapObj<mtClass> {
static size_t first_class_chunk_word_size() { return _first_class_chunk_word_size; }
char* bottom() const;
size_t used_words(MetadataType mdtype) const;
size_t used_words_slow(MetadataType mdtype) const;
size_t free_words(MetadataType mdtype) const;
size_t capacity_words(MetadataType mdtype) const;
size_t capacity_words_slow(MetadataType mdtype) const;
size_t waste_words(MetadataType mdtype) const;
size_t used_bytes_slow(MetadataType mdtype) const;
size_t capacity_bytes_slow(MetadataType mdtype) const;
static Metablock* allocate(ClassLoaderData* loader_data, size_t size,
bool read_only, MetadataType mdtype, TRAPS);
void deallocate(MetaWord* ptr, size_t byte_size, bool is_class);
@ -161,28 +168,81 @@ class Metaspace : public CHeapObj<mtClass> {
class MetaspaceAux : AllStatic {
// Statistics for class space and data space in metaspace.
static size_t used_in_bytes(Metaspace::MetadataType mdtype);
// These methods iterate over the classloader data graph
// for the given Metaspace type. These are slow.
static size_t used_bytes_slow(Metaspace::MetadataType mdtype);
static size_t free_in_bytes(Metaspace::MetadataType mdtype);
static size_t capacity_in_bytes(Metaspace::MetadataType mdtype);
static size_t capacity_bytes_slow(Metaspace::MetadataType mdtype);
// Iterates over the virtual space list.
static size_t reserved_in_bytes(Metaspace::MetadataType mdtype);
static size_t free_chunks_total(Metaspace::MetadataType mdtype);
static size_t free_chunks_total_in_bytes(Metaspace::MetadataType mdtype);
public:
// Total of space allocated to metadata in all Metaspaces
static size_t used_in_bytes() {
return used_in_bytes(Metaspace::ClassType) +
used_in_bytes(Metaspace::NonClassType);
// Running sum of space in all Metachunks that has been
// allocated to a Metaspace. This is used instead of
// iterating over all the classloaders
static size_t _allocated_capacity_words;
// Running sum of space in all Metachunks that have
// are being used for metadata.
static size_t _allocated_used_words;
public:
// Decrement and increment _allocated_capacity_words
static void dec_capacity(size_t words);
static void inc_capacity(size_t words);
// Decrement and increment _allocated_used_words
static void dec_used(size_t words);
static void inc_used(size_t words);
// Total of space allocated to metadata in all Metaspaces.
// This sums the space used in each Metachunk by
// iterating over the classloader data graph
static size_t used_bytes_slow() {
return used_bytes_slow(Metaspace::ClassType) +
used_bytes_slow(Metaspace::NonClassType);
}
// Total of available space in all Metaspaces
// Total of capacity allocated to all Metaspaces. This includes
// space in Metachunks not yet allocated and in the Metachunk
// freelist.
static size_t capacity_in_bytes() {
return capacity_in_bytes(Metaspace::ClassType) +
capacity_in_bytes(Metaspace::NonClassType);
// Used by MetaspaceCounters
static size_t free_chunks_total();
static size_t free_chunks_total_in_bytes();
static size_t allocated_capacity_words() {
return _allocated_capacity_words;
}
static size_t allocated_capacity_bytes() {
return _allocated_capacity_words * BytesPerWord;
}
static size_t allocated_used_words() {
return _allocated_used_words;
}
static size_t allocated_used_bytes() {
return _allocated_used_words * BytesPerWord;
}
static size_t free_bytes();
// Total capacity in all Metaspaces
static size_t capacity_bytes_slow() {
#ifdef PRODUCT
// Use allocated_capacity_bytes() in PRODUCT instead of this function.
guarantee(false, "Should not call capacity_bytes_slow() in the PRODUCT");
#endif
size_t class_capacity = capacity_bytes_slow(Metaspace::ClassType);
size_t non_class_capacity = capacity_bytes_slow(Metaspace::NonClassType);
assert(allocated_capacity_bytes() == class_capacity + non_class_capacity,
err_msg("bad accounting: allocated_capacity_bytes() " SIZE_FORMAT
" class_capacity + non_class_capacity " SIZE_FORMAT
" class_capacity " SIZE_FORMAT " non_class_capacity " SIZE_FORMAT,
allocated_capacity_bytes(), class_capacity + non_class_capacity,
class_capacity, non_class_capacity));
return class_capacity + non_class_capacity;
}
// Total space reserved in all Metaspaces
@ -201,6 +261,11 @@ class MetaspaceAux : AllStatic {
static void print_waste(outputStream* out);
static void dump(outputStream* out);
static void verify_free_chunks();
// Checks that the values returned by allocated_capacity_bytes() and
// capacity_bytes_slow() are the same.
static void verify_capacity();
static void verify_used();
static void verify_metrics();
};
// Metaspace are deallocated when their class loader are GC'ed.
@ -235,7 +300,6 @@ class MetaspaceGC : AllStatic {
public:
static size_t capacity_until_GC() { return _capacity_until_GC; }
static size_t capacity_until_GC_in_bytes() { return _capacity_until_GC * BytesPerWord; }
static void inc_capacity_until_GC(size_t v) { _capacity_until_GC += v; }
static void dec_capacity_until_GC(size_t v) {
_capacity_until_GC = _capacity_until_GC > v ? _capacity_until_GC - v : 0;

22
hotspot/src/share/vm/memory/metaspaceCounters.cpp
View File

@ -29,6 +29,16 @@
MetaspaceCounters* MetaspaceCounters::_metaspace_counters = NULL;
size_t MetaspaceCounters::calc_total_capacity() {
// The total capacity is the sum of
// 1) capacity of Metachunks in use by all Metaspaces
// 2) unused space at the end of each Metachunk
// 3) space in the freelist
size_t total_capacity = MetaspaceAux::allocated_capacity_bytes()
+ MetaspaceAux::free_bytes() + MetaspaceAux::free_chunks_total_in_bytes();
return total_capacity;
}
MetaspaceCounters::MetaspaceCounters() :
_capacity(NULL),
_used(NULL),
@ -36,8 +46,8 @@ MetaspaceCounters::MetaspaceCounters() :
if (UsePerfData) {
size_t min_capacity = MetaspaceAux::min_chunk_size();
size_t max_capacity = MetaspaceAux::reserved_in_bytes();
size_t curr_capacity = MetaspaceAux::capacity_in_bytes();
size_t used = MetaspaceAux::used_in_bytes();
size_t curr_capacity = calc_total_capacity();
size_t used = MetaspaceAux::allocated_used_bytes();
initialize(min_capacity, max_capacity, curr_capacity, used);
}
@ -82,15 +92,13 @@ void MetaspaceCounters::initialize(size_t min_capacity,
void MetaspaceCounters::update_capacity() {
assert(UsePerfData, "Should not be called unless being used");
assert(_capacity != NULL, "Should be initialized");
size_t capacity_in_bytes = MetaspaceAux::capacity_in_bytes();
_capacity->set_value(capacity_in_bytes);
size_t total_capacity = calc_total_capacity();
_capacity->set_value(total_capacity);
}
void MetaspaceCounters::update_used() {
assert(UsePerfData, "Should not be called unless being used");
assert(_used != NULL, "Should be initialized");
size_t used_in_bytes = MetaspaceAux::used_in_bytes();
size_t used_in_bytes = MetaspaceAux::allocated_used_bytes();
_used->set_value(used_in_bytes);
}

1
hotspot/src/share/vm/memory/metaspaceCounters.hpp
View File

@ -37,6 +37,7 @@ class MetaspaceCounters: public CHeapObj<mtClass> {
size_t max_capacity,
size_t curr_capacity,
size_t used);
size_t calc_total_capacity();
public:
MetaspaceCounters();
~MetaspaceCounters();

9
hotspot/src/share/vm/memory/metaspaceShared.cpp
View File

@ -376,18 +376,17 @@ void VM_PopulateDumpSharedSpace::doit() {
const char* fmt = "%s space: %9d [ %4.1f%% of total] out of %9d bytes [%4.1f%% used] at " PTR_FORMAT;
Metaspace* ro_space = _loader_data->ro_metaspace();
Metaspace* rw_space = _loader_data->rw_metaspace();
const size_t BPW = BytesPerWord;
// Allocated size of each space (may not be all occupied)
const size_t ro_alloced = ro_space->capacity_words(Metaspace::NonClassType) * BPW;
const size_t rw_alloced = rw_space->capacity_words(Metaspace::NonClassType) * BPW;
const size_t ro_alloced = ro_space->capacity_bytes_slow(Metaspace::NonClassType);
const size_t rw_alloced = rw_space->capacity_bytes_slow(Metaspace::NonClassType);
const size_t md_alloced = md_end-md_low;
const size_t mc_alloced = mc_end-mc_low;
const size_t total_alloced = ro_alloced + rw_alloced + md_alloced + mc_alloced;
// Occupied size of each space.
const size_t ro_bytes = ro_space->used_words(Metaspace::NonClassType) * BPW;
const size_t rw_bytes = rw_space->used_words(Metaspace::NonClassType) * BPW;
const size_t ro_bytes = ro_space->used_bytes_slow(Metaspace::NonClassType);
const size_t rw_bytes = rw_space->used_bytes_slow(Metaspace::NonClassType);
const size_t md_bytes = size_t(md_top - md_low);
const size_t mc_bytes = size_t(mc_top - mc_low);