Mercurial > hg > openjdk > jigsaw > hotspot
changeset 4585:a7fb14888912
8006952: Slow VM due to excessive code cache freelist iteration
Summary: Remove continous free block requirement
Reviewed-by: kvn
| author | neliasso |
|---|---|
| date | Thu, 11 Apr 2013 13:57:44 +0200 |
| parents | 4b2eebe03f93 |
| children | dedc8563e33d |
| files | src/share/vm/code/codeBlob.cpp src/share/vm/code/codeCache.cpp src/share/vm/code/codeCache.hpp src/share/vm/code/nmethod.cpp src/share/vm/compiler/compileBroker.cpp src/share/vm/memory/heap.cpp src/share/vm/memory/heap.hpp src/share/vm/opto/output.cpp |
| diffstat | 8 files changed, 123 insertions(+), 154 deletions(-) [+] |
line wrap: on
line diff
--- a/src/share/vm/code/codeBlob.cpp Tue Apr 16 10:04:01 2013 -0700 +++ b/src/share/vm/code/codeBlob.cpp Thu Apr 11 13:57:44 2013 +0200 @@ -348,14 +348,14 @@ void* RuntimeStub::operator new(size_t s, unsigned size) { - void* p = CodeCache::allocate(size); + void* p = CodeCache::allocate(size, true); if (!p) fatal("Initial size of CodeCache is too small"); return p; } // operator new shared by all singletons: void* SingletonBlob::operator new(size_t s, unsigned size) { - void* p = CodeCache::allocate(size); + void* p = CodeCache::allocate(size, true); if (!p) fatal("Initial size of CodeCache is too small"); return p; }
--- a/src/share/vm/code/codeCache.cpp Tue Apr 16 10:04:01 2013 -0700 +++ b/src/share/vm/code/codeCache.cpp Thu Apr 11 13:57:44 2013 +0200 @@ -172,7 +172,7 @@ static size_t maxCodeCacheUsed = 0; -CodeBlob* CodeCache::allocate(int size) { +CodeBlob* CodeCache::allocate(int size, bool is_critical) { // Do not seize the CodeCache lock here--if the caller has not // already done so, we are going to lose bigtime, since the code // cache will contain a garbage CodeBlob until the caller can @@ -183,7 +183,7 @@ CodeBlob* cb = NULL; _number_of_blobs++; while (true) { - cb = (CodeBlob*)_heap->allocate(size); + cb = (CodeBlob*)_heap->allocate(size, is_critical); if (cb != NULL) break; if (!_heap->expand_by(CodeCacheExpansionSize)) { // Expansion failed @@ -192,8 +192,8 @@ if (PrintCodeCacheExtension) { ResourceMark rm; tty->print_cr("code cache extended to [" INTPTR_FORMAT ", " INTPTR_FORMAT "] (%d bytes)", - (intptr_t)_heap->begin(), (intptr_t)_heap->end(), - (address)_heap->end() - (address)_heap->begin()); + (intptr_t)_heap->low_boundary(), (intptr_t)_heap->high(), + (address)_heap->high() - (address)_heap->low_boundary()); } } maxCodeCacheUsed = MAX2(maxCodeCacheUsed, ((address)_heap->high_boundary() - @@ -608,13 +608,13 @@ address CodeCache::first_address() { assert_locked_or_safepoint(CodeCache_lock); - return (address)_heap->begin(); + return (address)_heap->low_boundary(); } address CodeCache::last_address() { assert_locked_or_safepoint(CodeCache_lock); - return (address)_heap->end(); + return (address)_heap->high(); } @@ -996,10 +996,9 @@ void CodeCache::print_summary(outputStream* st, bool detailed) { size_t total = (_heap->high_boundary() - _heap->low_boundary()); st->print_cr("CodeCache: size=" SIZE_FORMAT "Kb used=" SIZE_FORMAT - "Kb max_used=" SIZE_FORMAT "Kb free=" SIZE_FORMAT - "Kb max_free_chunk=" SIZE_FORMAT "Kb", + "Kb max_used=" SIZE_FORMAT "Kb free=" SIZE_FORMAT "Kb", total/K, (total - unallocated_capacity())/K, - maxCodeCacheUsed/K, unallocated_capacity()/K, largest_free_block()/K); + maxCodeCacheUsed/K, unallocated_capacity()/K); if (detailed) { st->print_cr(" bounds [" INTPTR_FORMAT ", " INTPTR_FORMAT ", " INTPTR_FORMAT "]", @@ -1018,19 +1017,8 @@ void CodeCache::log_state(outputStream* st) { st->print(" total_blobs='" UINT32_FORMAT "' nmethods='" UINT32_FORMAT "'" - " adapters='" UINT32_FORMAT "' free_code_cache='" SIZE_FORMAT "'" - " largest_free_block='" SIZE_FORMAT "'", + " adapters='" UINT32_FORMAT "' free_code_cache='" SIZE_FORMAT "'", nof_blobs(), nof_nmethods(), nof_adapters(), - unallocated_capacity(), largest_free_block()); + unallocated_capacity()); } -size_t CodeCache::largest_free_block() { - // This is called both with and without CodeCache_lock held so - // handle both cases. - if (CodeCache_lock->owned_by_self()) { - return _heap->largest_free_block(); - } else { - MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); - return _heap->largest_free_block(); - } -}
--- a/src/share/vm/code/codeCache.hpp Tue Apr 16 10:04:01 2013 -0700 +++ b/src/share/vm/code/codeCache.hpp Thu Apr 11 13:57:44 2013 +0200 @@ -70,7 +70,7 @@ static void initialize(); // Allocation/administration - static CodeBlob* allocate(int size); // allocates a new CodeBlob + static CodeBlob* allocate(int size, bool is_critical = false); // allocates a new CodeBlob static void commit(CodeBlob* cb); // called when the allocated CodeBlob has been filled static int alignment_unit(); // guaranteed alignment of all CodeBlobs static int alignment_offset(); // guaranteed offset of first CodeBlob byte within alignment unit (i.e., allocation header) @@ -156,19 +156,13 @@ static address low_bound() { return (address) _heap->low_boundary(); } static address high_bound() { return (address) _heap->high_boundary(); } - static bool has_space(int size) { - // Always leave some room in the CodeCache for I2C/C2I adapters - return largest_free_block() > (CodeCacheMinimumFreeSpace + size); - } - // Profiling static address first_address(); // first address used for CodeBlobs static address last_address(); // last address used for CodeBlobs static size_t capacity() { return _heap->capacity(); } static size_t max_capacity() { return _heap->max_capacity(); } static size_t unallocated_capacity() { return _heap->unallocated_capacity(); } - static size_t largest_free_block(); - static bool needs_flushing() { return largest_free_block() < CodeCacheFlushingMinimumFreeSpace; } + static bool needs_flushing() { return unallocated_capacity() < CodeCacheFlushingMinimumFreeSpace; } static bool needs_cache_clean() { return _needs_cache_clean; } static void set_needs_cache_clean(bool v) { _needs_cache_clean = v; }
--- a/src/share/vm/code/nmethod.cpp Tue Apr 16 10:04:01 2013 -0700 +++ b/src/share/vm/code/nmethod.cpp Thu Apr 11 13:57:44 2013 +0200 @@ -501,18 +501,17 @@ { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); int native_nmethod_size = allocation_size(code_buffer, sizeof(nmethod)); - if (CodeCache::has_space(native_nmethod_size)) { - CodeOffsets offsets; - offsets.set_value(CodeOffsets::Verified_Entry, vep_offset); - offsets.set_value(CodeOffsets::Frame_Complete, frame_complete); - nm = new (native_nmethod_size) nmethod(method(), native_nmethod_size, - compile_id, &offsets, - code_buffer, frame_size, - basic_lock_owner_sp_offset, - basic_lock_sp_offset, oop_maps); - NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm)); - if (PrintAssembly && nm != NULL) - Disassembler::decode(nm); + CodeOffsets offsets; + offsets.set_value(CodeOffsets::Verified_Entry, vep_offset); + offsets.set_value(CodeOffsets::Frame_Complete, frame_complete); + nm = new (native_nmethod_size) nmethod(method(), native_nmethod_size, + compile_id, &offsets, + code_buffer, frame_size, + basic_lock_owner_sp_offset, + basic_lock_sp_offset, oop_maps); + NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_native_nmethod(nm)); + if (PrintAssembly && nm != NULL) { + Disassembler::decode(nm); } } // verify nmethod @@ -538,18 +537,17 @@ { MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag); int nmethod_size = allocation_size(code_buffer, sizeof(nmethod)); - if (CodeCache::has_space(nmethod_size)) { - CodeOffsets offsets; - offsets.set_value(CodeOffsets::Verified_Entry, vep_offset); - offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset); - offsets.set_value(CodeOffsets::Frame_Complete, frame_complete); + CodeOffsets offsets; + offsets.set_value(CodeOffsets::Verified_Entry, vep_offset); + offsets.set_value(CodeOffsets::Dtrace_trap, trap_offset); + offsets.set_value(CodeOffsets::Frame_Complete, frame_complete); - nm = new (nmethod_size) nmethod(method(), nmethod_size, - &offsets, code_buffer, frame_size); + nm = new (nmethod_size) nmethod(method(), nmethod_size, + &offsets, code_buffer, frame_size); - NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm)); - if (PrintAssembly && nm != NULL) - Disassembler::decode(nm); + NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm)); + if (PrintAssembly && nm != NULL) { + Disassembler::decode(nm); } } // verify nmethod @@ -591,16 +589,16 @@ + round_to(handler_table->size_in_bytes(), oopSize) + round_to(nul_chk_table->size_in_bytes(), oopSize) + round_to(debug_info->data_size() , oopSize); - if (CodeCache::has_space(nmethod_size)) { - nm = new (nmethod_size) - nmethod(method(), nmethod_size, compile_id, entry_bci, offsets, - orig_pc_offset, debug_info, dependencies, code_buffer, frame_size, - oop_maps, - handler_table, - nul_chk_table, - compiler, - comp_level); - } + + nm = new (nmethod_size) + nmethod(method(), nmethod_size, compile_id, entry_bci, offsets, + orig_pc_offset, debug_info, dependencies, code_buffer, frame_size, + oop_maps, + handler_table, + nul_chk_table, + compiler, + comp_level); + if (nm != NULL) { // To make dependency checking during class loading fast, record // the nmethod dependencies in the classes it is dependent on. @@ -612,15 +610,18 @@ // classes the slow way is too slow. for (Dependencies::DepStream deps(nm); deps.next(); ) { Klass* klass = deps.context_type(); - if (klass == NULL) continue; // ignore things like evol_method + if (klass == NULL) { + continue; // ignore things like evol_method + } // record this nmethod as dependent on this klass InstanceKlass::cast(klass)->add_dependent_nmethod(nm); } } NOT_PRODUCT(if (nm != NULL) nmethod_stats.note_nmethod(nm)); - if (PrintAssembly && nm != NULL) + if (PrintAssembly && nm != NULL) { Disassembler::decode(nm); + } } // verify nmethod @@ -798,13 +799,11 @@ } #endif // def HAVE_DTRACE_H -void* nmethod::operator new(size_t size, int nmethod_size) { - void* alloc = CodeCache::allocate(nmethod_size); - guarantee(alloc != NULL, "CodeCache should have enough space"); - return alloc; +void* nmethod::operator new(size_t size, int nmethod_size) throw () { + // Not critical, may return null if there is too little continuous memory + return CodeCache::allocate(nmethod_size); } - nmethod::nmethod( Method* method, int nmethod_size,
--- a/src/share/vm/compiler/compileBroker.cpp Tue Apr 16 10:04:01 2013 -0700 +++ b/src/share/vm/compiler/compileBroker.cpp Thu Apr 11 13:57:44 2013 +0200 @@ -1581,7 +1581,7 @@ // We need this HandleMark to avoid leaking VM handles. HandleMark hm(thread); - if (CodeCache::largest_free_block() < CodeCacheMinimumFreeSpace) { + if (CodeCache::unallocated_capacity() < CodeCacheMinimumFreeSpace) { // the code cache is really full handle_full_code_cache(); } else if (UseCodeCacheFlushing && CodeCache::needs_flushing()) {
--- a/src/share/vm/memory/heap.cpp Tue Apr 16 10:04:01 2013 -0700 +++ b/src/share/vm/memory/heap.cpp Thu Apr 11 13:57:44 2013 +0200 @@ -42,7 +42,7 @@ _log2_segment_size = 0; _next_segment = 0; _freelist = NULL; - _free_segments = 0; + _freelist_segments = 0; } @@ -115,8 +115,8 @@ } on_code_mapping(_memory.low(), _memory.committed_size()); - _number_of_committed_segments = number_of_segments(_memory.committed_size()); - _number_of_reserved_segments = number_of_segments(_memory.reserved_size()); + _number_of_committed_segments = size_to_segments(_memory.committed_size()); + _number_of_reserved_segments = size_to_segments(_memory.reserved_size()); assert(_number_of_reserved_segments >= _number_of_committed_segments, "just checking"); // reserve space for _segmap @@ -149,8 +149,8 @@ if (!_memory.expand_by(dm)) return false; on_code_mapping(base, dm); size_t i = _number_of_committed_segments; - _number_of_committed_segments = number_of_segments(_memory.committed_size()); - assert(_number_of_reserved_segments == number_of_segments(_memory.reserved_size()), "number of reserved segments should not change"); + _number_of_committed_segments = size_to_segments(_memory.committed_size()); + assert(_number_of_reserved_segments == size_to_segments(_memory.reserved_size()), "number of reserved segments should not change"); assert(_number_of_reserved_segments >= _number_of_committed_segments, "just checking"); // expand _segmap space size_t ds = align_to_page_size(_number_of_committed_segments) - _segmap.committed_size(); @@ -176,33 +176,44 @@ } -void* CodeHeap::allocate(size_t size) { - size_t length = number_of_segments(size + sizeof(HeapBlock)); - assert(length *_segment_size >= sizeof(FreeBlock), "not enough room for FreeList"); +void* CodeHeap::allocate(size_t instance_size, bool is_critical) { + size_t number_of_segments = size_to_segments(instance_size + sizeof(HeapBlock)); + assert(segments_to_size(number_of_segments) >= sizeof(FreeBlock), "not enough room for FreeList"); // First check if we can satify request from freelist debug_only(verify()); - HeapBlock* block = search_freelist(length); + HeapBlock* block = search_freelist(number_of_segments, is_critical); debug_only(if (VerifyCodeCacheOften) verify()); if (block != NULL) { - assert(block->length() >= length && block->length() < length + CodeCacheMinBlockLength, "sanity check"); + assert(block->length() >= number_of_segments && block->length() < number_of_segments + CodeCacheMinBlockLength, "sanity check"); assert(!block->free(), "must be marked free"); #ifdef ASSERT - memset((void *)block->allocated_space(), badCodeHeapNewVal, size); + memset((void *)block->allocated_space(), badCodeHeapNewVal, instance_size); #endif return block->allocated_space(); } - if (length < CodeCacheMinBlockLength) { - length = CodeCacheMinBlockLength; + // Ensure minimum size for allocation to the heap. + if (number_of_segments < CodeCacheMinBlockLength) { + number_of_segments = CodeCacheMinBlockLength; } - if (_next_segment + length <= _number_of_committed_segments) { - mark_segmap_as_used(_next_segment, _next_segment + length); + + if (!is_critical) { + // Make sure the allocation fits in the unallocated heap without using + // the CodeCacheMimimumFreeSpace that is reserved for critical allocations. + if (segments_to_size(number_of_segments) > (heap_unallocated_capacity() - CodeCacheMinimumFreeSpace)) { + // Fail allocation + return NULL; + } + } + + if (_next_segment + number_of_segments <= _number_of_committed_segments) { + mark_segmap_as_used(_next_segment, _next_segment + number_of_segments); HeapBlock* b = block_at(_next_segment); - b->initialize(length); - _next_segment += length; + b->initialize(number_of_segments); + _next_segment += number_of_segments; #ifdef ASSERT - memset((void *)b->allocated_space(), badCodeHeapNewVal, size); + memset((void *)b->allocated_space(), badCodeHeapNewVal, instance_size); #endif return b->allocated_space(); } else { @@ -219,7 +230,7 @@ #ifdef ASSERT memset((void *)b->allocated_space(), badCodeHeapFreeVal, - size(b->length()) - sizeof(HeapBlock)); + segments_to_size(b->length()) - sizeof(HeapBlock)); #endif add_to_freelist(b); @@ -299,32 +310,14 @@ } size_t CodeHeap::allocated_capacity() const { - // Start with the committed size in _memory; - size_t l = _memory.committed_size(); - - // Subtract the committed, but unused, segments - l -= size(_number_of_committed_segments - _next_segment); - - // Subtract the size of the freelist - l -= size(_free_segments); - - return l; + // size of used heap - size on freelist + return segments_to_size(_next_segment - _freelist_segments); } -size_t CodeHeap::largest_free_block() const { - // First check unused space excluding free blocks. - size_t free_sz = size(_free_segments); - size_t unused = max_capacity() - allocated_capacity() - free_sz; - if (unused >= free_sz) - return unused; - - // Now check largest free block. - size_t len = 0; - for (FreeBlock* b = _freelist; b != NULL; b = b->link()) { - if (b->length() > len) - len = b->length(); - } - return MAX2(unused, size(len)); +// Returns size of the unallocated heap block +size_t CodeHeap::heap_unallocated_capacity() const { + // Total number of segments - number currently used + return segments_to_size(_number_of_reserved_segments - _next_segment); } // Free list management @@ -365,7 +358,7 @@ assert(b != _freelist, "cannot be removed twice"); // Mark as free and update free space count - _free_segments += b->length(); + _freelist_segments += b->length(); b->set_free(); // First element in list? @@ -400,7 +393,7 @@ // Search freelist for an entry on the list with the best fit // Return NULL if no one was found -FreeBlock* CodeHeap::search_freelist(size_t length) { +FreeBlock* CodeHeap::search_freelist(size_t length, bool is_critical) { FreeBlock *best_block = NULL; FreeBlock *best_prev = NULL; size_t best_length = 0; @@ -411,6 +404,16 @@ while(cur != NULL) { size_t l = cur->length(); if (l >= length && (best_block == NULL || best_length > l)) { + + // Non critical allocations are not allowed to use the last part of the code heap. + if (!is_critical) { + // Make sure the end of the allocation doesn't cross into the last part of the code heap + if (((size_t)cur + length) > ((size_t)high_boundary() - CodeCacheMinimumFreeSpace)) { + // the freelist is sorted by address - if one fails, all consecutive will also fail. + break; + } + } + // Remember best block, its previous element, and its length best_block = cur; best_prev = prev; @@ -452,7 +455,7 @@ } best_block->set_used(); - _free_segments -= length; + _freelist_segments -= length; return best_block; } @@ -478,7 +481,7 @@ } // Verify that freelist contains the right amount of free space - // guarantee(len == _free_segments, "wrong freelist"); + // guarantee(len == _freelist_segments, "wrong freelist"); // Verify that the number of free blocks is not out of hand. static int free_block_threshold = 10000;
--- a/src/share/vm/memory/heap.hpp Tue Apr 16 10:04:01 2013 -0700 +++ b/src/share/vm/memory/heap.hpp Thu Apr 11 13:57:44 2013 +0200 @@ -91,11 +91,11 @@ size_t _next_segment; FreeBlock* _freelist; - size_t _free_segments; // No. of segments in freelist + size_t _freelist_segments; // No. of segments in freelist // Helper functions - size_t number_of_segments(size_t size) const { return (size + _segment_size - 1) >> _log2_segment_size; } - size_t size(size_t number_of_segments) const { return number_of_segments << _log2_segment_size; } + size_t size_to_segments(size_t size) const { return (size + _segment_size - 1) >> _log2_segment_size; } + size_t segments_to_size(size_t number_of_segments) const { return number_of_segments << _log2_segment_size; } size_t segment_for(void* p) const { return ((char*)p - _memory.low()) >> _log2_segment_size; } HeapBlock* block_at(size_t i) const { return (HeapBlock*)(_memory.low() + (i << _log2_segment_size)); } @@ -110,7 +110,7 @@ // Toplevel freelist management void add_to_freelist(HeapBlock *b); - FreeBlock* search_freelist(size_t length); + FreeBlock* search_freelist(size_t length, bool is_critical); // Iteration helpers void* next_free(HeapBlock* b) const; @@ -132,22 +132,19 @@ void clear(); // clears all heap contents // Memory allocation - void* allocate (size_t size); // allocates a block of size or returns NULL + void* allocate (size_t size, bool is_critical); // allocates a block of size or returns NULL void deallocate(void* p); // deallocates a block // Attributes - void* begin() const { return _memory.low (); } - void* end() const { return _memory.high(); } - bool contains(void* p) const { return begin() <= p && p < end(); } - void* find_start(void* p) const; // returns the block containing p or NULL - size_t alignment_unit() const; // alignment of any block - size_t alignment_offset() const; // offset of first byte of any block, within the enclosing alignment unit - static size_t header_size(); // returns the header size for each heap block + char* low_boundary() const { return _memory.low_boundary (); } + char* high() const { return _memory.high(); } + char* high_boundary() const { return _memory.high_boundary(); } - // Returns reserved area high and low addresses - char *low_boundary() const { return _memory.low_boundary (); } - char *high() const { return _memory.high(); } - char *high_boundary() const { return _memory.high_boundary(); } + bool contains(const void* p) const { return low_boundary() <= p && p < high(); } + void* find_start(void* p) const; // returns the block containing p or NULL + size_t alignment_unit() const; // alignment of any block + size_t alignment_offset() const; // offset of first byte of any block, within the enclosing alignment unit + static size_t header_size(); // returns the header size for each heap block // Iteration @@ -161,8 +158,11 @@ size_t max_capacity() const; size_t allocated_capacity() const; size_t unallocated_capacity() const { return max_capacity() - allocated_capacity(); } - size_t largest_free_block() const; +private: + size_t heap_unallocated_capacity() const; + +public: // Debugging void verify(); void print() PRODUCT_RETURN;
--- a/src/share/vm/opto/output.cpp Tue Apr 16 10:04:01 2013 -0700 +++ b/src/share/vm/opto/output.cpp Thu Apr 11 13:57:44 2013 +0200 @@ -1044,21 +1044,6 @@ debug_info->end_non_safepoint(pc_offset); } - - -// helper for fill_buffer bailout logic -static void turn_off_compiler(Compile* C) { - if (CodeCache::largest_free_block() >= CodeCacheMinimumFreeSpace*10) { - // Do not turn off compilation if a single giant method has - // blown the code cache size. - C->record_failure("excessive request to CodeCache"); - } else { - // Let CompilerBroker disable further compilations. - C->record_failure("CodeCache is full"); - } -} - - //------------------------------init_buffer------------------------------------ CodeBuffer* Compile::init_buffer(uint* blk_starts) { @@ -1158,7 +1143,7 @@ // Have we run out of code space? if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { - turn_off_compiler(this); + C->record_failure("CodeCache is full"); return NULL; } // Configure the code buffer. @@ -1476,7 +1461,7 @@ // Verify that there is sufficient space remaining cb->insts()->maybe_expand_to_ensure_remaining(MAX_inst_size); if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { - turn_off_compiler(this); + C->record_failure("CodeCache is full"); return; } @@ -1633,7 +1618,7 @@ // One last check for failed CodeBuffer::expand: if ((cb->blob() == NULL) || (!CompileBroker::should_compile_new_jobs())) { - turn_off_compiler(this); + C->record_failure("CodeCache is full"); return; }