# HG changeset patch # User anoll # Date 1394174560 -3600 # Node ID b6426873cb374c9c901a2b43d92f0afecf0d24b9 # Parent 141e27fa5a42deab3843d65e8faa5e8dd8f7cd46 8029799: vm/mlvm/anonloader/stress/oome prints warning: CodeHeap: # of free blocks > 10000 Summary: Double CodeCacheSegmentSize from 64 byte to 128 bytes if tiered compilation is enabled Reviewed-by: kvn, twisti diff -r 141e27fa5a42 -r b6426873cb37 hotspot/src/share/vm/code/codeCache.cpp --- a/hotspot/src/share/vm/code/codeCache.cpp Thu Mar 06 14:35:26 2014 +0100 +++ b/hotspot/src/share/vm/code/codeCache.cpp Fri Mar 07 07:42:40 2014 +0100 @@ -198,14 +198,12 @@ } maxCodeCacheUsed = MAX2(maxCodeCacheUsed, ((address)_heap->high_boundary() - (address)_heap->low_boundary()) - unallocated_capacity()); - verify_if_often(); print_trace("allocation", cb, size); return cb; } void CodeCache::free(CodeBlob* cb) { assert_locked_or_safepoint(CodeCache_lock); - verify_if_often(); print_trace("free", cb); if (cb->is_nmethod()) { @@ -221,7 +219,6 @@ _heap->deallocate(cb); - verify_if_often(); assert(_number_of_blobs >= 0, "sanity check"); } @@ -244,12 +241,6 @@ } -void CodeCache::flush() { - assert_locked_or_safepoint(CodeCache_lock); - Unimplemented(); -} - - // Iteration over CodeBlobs #define FOR_ALL_BLOBS(var) for (CodeBlob *var = first() ; var != NULL; var = next(var) ) @@ -269,7 +260,7 @@ CodeBlob* CodeCache::find_blob(void* start) { CodeBlob* result = find_blob_unsafe(start); if (result == NULL) return NULL; - // We could potientially look up non_entrant methods + // We could potentially look up non_entrant methods guarantee(!result->is_zombie() || result->is_locked_by_vm() || is_error_reported(), "unsafe access to zombie method"); return result; } @@ -741,17 +732,26 @@ } } +void CodeCache::print_memory_overhead() { + size_t wasted_bytes = 0; + CodeBlob *cb; + for (cb = first(); cb != NULL; cb = next(cb)) { + HeapBlock* heap_block = ((HeapBlock*)cb) - 1; + wasted_bytes += heap_block->length() * CodeCacheSegmentSize - cb->size(); + } + // Print bytes that are allocated in the freelist + ttyLocker ttl; + tty->print_cr("Number of elements in freelist: %d", freelist_length()); + tty->print_cr("Allocated in freelist: %dkB", bytes_allocated_in_freelist()/K); + tty->print_cr("Unused bytes in CodeBlobs: %dkB", (int)(wasted_bytes/K)); + tty->print_cr("Segment map size: %dkB", allocated_segments()/K); // 1 byte per segment +} + //------------------------------------------------------------------------------------------------ // Non-product version #ifndef PRODUCT -void CodeCache::verify_if_often() { - if (VerifyCodeCacheOften) { - _heap->verify(); - } -} - void CodeCache::print_trace(const char* event, CodeBlob* cb, int size) { if (PrintCodeCache2) { // Need to add a new flag ResourceMark rm; @@ -774,7 +774,7 @@ int nmethodUnloaded = 0; int nmethodJava = 0; int nmethodNative = 0; - int maxCodeSize = 0; + int max_nm_size = 0; ResourceMark rm; CodeBlob *cb; @@ -798,13 +798,11 @@ if(nm->is_not_entrant()) { nmethodNotEntrant++; } if(nm->is_zombie()) { nmethodZombie++; } if(nm->is_unloaded()) { nmethodUnloaded++; } - if(nm->is_native_method()) { nmethodNative++; } + if(nm->method() != NULL && nm->is_native_method()) { nmethodNative++; } if(nm->method() != NULL && nm->is_java_method()) { nmethodJava++; - if (nm->insts_size() > maxCodeSize) { - maxCodeSize = nm->insts_size(); - } + max_nm_size = MAX2(max_nm_size, nm->size()); } } else if (cb->is_runtime_stub()) { runtimeStubCount++; @@ -820,18 +818,19 @@ } int bucketSize = 512; - int bucketLimit = maxCodeSize / bucketSize + 1; + int bucketLimit = max_nm_size / bucketSize + 1; int *buckets = NEW_C_HEAP_ARRAY(int, bucketLimit, mtCode); - memset(buckets,0,sizeof(int) * bucketLimit); + memset(buckets, 0, sizeof(int) * bucketLimit); for (cb = first(); cb != NULL; cb = next(cb)) { if (cb->is_nmethod()) { nmethod* nm = (nmethod*)cb; if(nm->is_java_method()) { - buckets[nm->insts_size() / bucketSize]++; - } + buckets[nm->size() / bucketSize]++; + } } } + tty->print_cr("Code Cache Entries (total of %d)",total); tty->print_cr("-------------------------------------------------"); tty->print_cr("nmethods: %d",nmethodCount); @@ -858,6 +857,7 @@ } FREE_C_HEAP_ARRAY(int, buckets, mtCode); + print_memory_overhead(); } #endif // !PRODUCT diff -r 141e27fa5a42 -r b6426873cb37 hotspot/src/share/vm/code/codeCache.hpp --- a/hotspot/src/share/vm/code/codeCache.hpp Thu Mar 06 14:35:26 2014 +0100 +++ b/hotspot/src/share/vm/code/codeCache.hpp Fri Mar 07 07:42:40 2014 +0100 @@ -58,12 +58,13 @@ static bool _needs_cache_clean; static nmethod* _scavenge_root_nmethods; // linked via nm->scavenge_root_link() - static void verify_if_often() PRODUCT_RETURN; - static void mark_scavenge_root_nmethods() PRODUCT_RETURN; static void verify_perm_nmethods(CodeBlobClosure* f_or_null) PRODUCT_RETURN; static int _codemem_full_count; + static size_t bytes_allocated_in_freelist() { return _heap->allocated_in_freelist(); } + static int allocated_segments() { return _heap->allocated_segments(); } + static size_t freelist_length() { return _heap->freelist_length(); } public: @@ -78,7 +79,6 @@ 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) static void free(CodeBlob* cb); // frees a CodeBlob - static void flush(); // flushes all CodeBlobs static bool contains(void *p); // returns whether p is included static void blobs_do(void f(CodeBlob* cb)); // iterates over all CodeBlobs static void blobs_do(CodeBlobClosure* f); // iterates over all CodeBlobs @@ -150,6 +150,7 @@ // Printing/debugging static void print(); // prints summary static void print_internals(); + static void print_memory_overhead(); static void verify(); // verifies the code cache static void print_trace(const char* event, CodeBlob* cb, int size = 0) PRODUCT_RETURN; static void print_summary(outputStream* st, bool detailed = true); // Prints a summary of the code cache usage diff -r 141e27fa5a42 -r b6426873cb37 hotspot/src/share/vm/memory/heap.cpp --- a/hotspot/src/share/vm/memory/heap.cpp Thu Mar 06 14:35:26 2014 +0100 +++ b/hotspot/src/share/vm/memory/heap.cpp Fri Mar 07 07:42:40 2014 +0100 @@ -43,6 +43,7 @@ _next_segment = 0; _freelist = NULL; _freelist_segments = 0; + _freelist_length = 0; } @@ -53,7 +54,7 @@ address p = (address)_segmap.low() + beg; address q = (address)_segmap.low() + end; // initialize interval - while (p < q) *p++ = 0xFF; + while (p < q) *p++ = free_sentinel; } @@ -67,7 +68,7 @@ int i = 0; while (p < q) { *p++ = i++; - if (i == 0xFF) i = 1; + if (i == free_sentinel) i = 1; } } @@ -139,11 +140,6 @@ } -void CodeHeap::release() { - Unimplemented(); -} - - bool CodeHeap::expand_by(size_t size) { // expand _memory space size_t dm = align_to_page_size(_memory.committed_size() + size) - _memory.committed_size(); @@ -157,8 +153,8 @@ 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(); - if (ds > 0) { - if (!_segmap.expand_by(ds)) return false; + if ((ds > 0) && !_segmap.expand_by(ds)) { + return false; } assert(_segmap.committed_size() >= (size_t) _number_of_committed_segments, "just checking"); // initialize additional segmap entries @@ -167,12 +163,6 @@ return true; } - -void CodeHeap::shrink_by(size_t size) { - Unimplemented(); -} - - void CodeHeap::clear() { _next_segment = 0; mark_segmap_as_free(0, _number_of_committed_segments); @@ -180,26 +170,23 @@ void* CodeHeap::allocate(size_t instance_size, bool is_critical) { - size_t number_of_segments = size_to_segments(instance_size + sizeof(HeapBlock)); + size_t number_of_segments = size_to_segments(instance_size + header_size()); assert(segments_to_size(number_of_segments) >= sizeof(FreeBlock), "not enough room for FreeList"); // First check if we can satisfy request from freelist - debug_only(verify()); + NOT_PRODUCT(verify()); HeapBlock* block = search_freelist(number_of_segments, is_critical); - debug_only(if (VerifyCodeCacheOften) verify()); + NOT_PRODUCT(verify()); + if (block != NULL) { 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, instance_size); -#endif + DEBUG_ONLY(memset((void*)block->allocated_space(), badCodeHeapNewVal, instance_size)); return block->allocated_space(); } // Ensure minimum size for allocation to the heap. - if (number_of_segments < CodeCacheMinBlockLength) { - number_of_segments = CodeCacheMinBlockLength; - } + number_of_segments = MAX2((int)CodeCacheMinBlockLength, (int)number_of_segments); if (!is_critical) { // Make sure the allocation fits in the unallocated heap without using @@ -215,9 +202,7 @@ HeapBlock* b = block_at(_next_segment); b->initialize(number_of_segments); _next_segment += number_of_segments; -#ifdef ASSERT - memset((void *)b->allocated_space(), badCodeHeapNewVal, instance_size); -#endif + DEBUG_ONLY(memset((void *)b->allocated_space(), badCodeHeapNewVal, instance_size)); return b->allocated_space(); } else { return NULL; @@ -230,28 +215,56 @@ // Find start of HeapBlock HeapBlock* b = (((HeapBlock *)p) - 1); assert(b->allocated_space() == p, "sanity check"); -#ifdef ASSERT - memset((void *)b->allocated_space(), - badCodeHeapFreeVal, - segments_to_size(b->length()) - sizeof(HeapBlock)); -#endif + DEBUG_ONLY(memset((void *)b->allocated_space(), badCodeHeapFreeVal, + segments_to_size(b->length()) - sizeof(HeapBlock))); add_to_freelist(b); - - debug_only(if (VerifyCodeCacheOften) verify()); + NOT_PRODUCT(verify()); } - +/** + * Uses segment map to find the the start (header) of a nmethod. This works as follows: + * The memory of the code cache is divided into 'segments'. The size of a segment is + * determined by -XX:CodeCacheSegmentSize=XX. Allocation in the code cache can only + * happen at segment boundaries. A pointer in the code cache can be mapped to a segment + * by calling segment_for(addr). Each time memory is requested from the code cache, + * the segmap is updated accordingly. See the following example, which illustrates the + * state of code cache and the segment map: (seg -> segment, nm ->nmethod) + * + * code cache segmap + * ----------- --------- + * seg 1 | nm 1 | -> | 0 | + * seg 2 | nm 1 | -> | 1 | + * ... | nm 1 | -> | .. | + * seg m | nm 2 | -> | 0 | + * seg m+1 | nm 2 | -> | 1 | + * ... | nm 2 | -> | 2 | + * ... | nm 2 | -> | .. | + * ... | nm 2 | -> | 0xFE | + * seg m+n | nm 2 | -> | 1 | + * ... | nm 2 | -> | | + * + * A value of '0' in the segmap indicates that this segment contains the beginning of + * an nmethod. Let's walk through a simple example: If we want to find the start of + * an nmethod that falls into seg 2, we read the value of the segmap[2]. The value + * is an offset that points to the segment that contains the start of the nmethod. + * Another example: If we want to get the start of nm 2, and we happen to get a pointer + * that points to seg m+n, we first read seg[n+m], which returns '1'. So we have to + * do one more read of the segmap[m+n-1] to finally get the segment header. + */ void* CodeHeap::find_start(void* p) const { if (!contains(p)) { return NULL; } - size_t i = segment_for(p); - address b = (address)_segmap.low(); - if (b[i] == 0xFF) { + size_t seg_idx = segment_for(p); + address seg_map = (address)_segmap.low(); + if (is_segment_unused(seg_map[seg_idx])) { return NULL; } - while (b[i] > 0) i -= (int)b[i]; - HeapBlock* h = block_at(i); + while (seg_map[seg_idx] > 0) { + seg_idx -= (int)seg_map[seg_idx]; + } + + HeapBlock* h = block_at(seg_idx); if (h->free()) { return NULL; } @@ -272,7 +285,7 @@ } // Finds the next free heapblock. If the current one is free, that it returned -void* CodeHeap::next_free(HeapBlock *b) const { +void* CodeHeap::next_free(HeapBlock* b) const { // Since free blocks are merged, there is max. on free block // between two used ones if (b != NULL && b->free()) b = next_block(b); @@ -287,7 +300,7 @@ return NULL; } -HeapBlock *CodeHeap::block_start(void *q) const { +HeapBlock* CodeHeap::block_start(void* q) const { HeapBlock* b = (HeapBlock*)find_start(q); if (b == NULL) return NULL; return b - 1; @@ -312,6 +325,10 @@ return _memory.reserved_size(); } +int CodeHeap::allocated_segments() const { + return (int)_next_segment; +} + size_t CodeHeap::allocated_capacity() const { // size of used heap - size on freelist return segments_to_size(_next_segment - _freelist_segments); @@ -325,7 +342,7 @@ // Free list management -FreeBlock *CodeHeap::following_block(FreeBlock *b) { +FreeBlock* CodeHeap::following_block(FreeBlock *b) { return (FreeBlock*)(((address)b) + _segment_size * b->length()); } @@ -343,7 +360,7 @@ } // Try to merge this block with the following block -void CodeHeap::merge_right(FreeBlock *a) { +bool CodeHeap::merge_right(FreeBlock* a) { assert(a->free(), "must be a free block"); if (following_block(a) == a->link()) { assert(a->link() != NULL && a->link()->free(), "must be free too"); @@ -353,13 +370,20 @@ // Update find_start map size_t beg = segment_for(a); mark_segmap_as_used(beg, beg + a->length()); + _freelist_length--; + return true; } + return false; } -void CodeHeap::add_to_freelist(HeapBlock *a) { + +void CodeHeap::add_to_freelist(HeapBlock* a) { FreeBlock* b = (FreeBlock*)a; + _freelist_length++; + assert(b != _freelist, "cannot be removed twice"); + // Mark as free and update free space count _freelist_segments += b->length(); b->set_free(); @@ -371,95 +395,96 @@ return; } - // Scan for right place to put into list. List - // is sorted by increasing addresses - FreeBlock* prev = NULL; - FreeBlock* cur = _freelist; - while(cur != NULL && cur < b) { - assert(prev == NULL || prev < cur, "must be ordered"); - prev = cur; - cur = cur->link(); - } - - assert( (prev == NULL && b < _freelist) || - (prev < b && (cur == NULL || b < cur)), "list must be ordered"); - - if (prev == NULL) { + // Since the freelist is ordered (smaller addresses -> larger addresses) and the + // element we want to insert into the freelist has a smaller address than the first + // element, we can simply add 'b' as the first element and we are done. + if (b < _freelist) { // Insert first in list b->set_link(_freelist); _freelist = b; merge_right(_freelist); - } else { - insert_after(prev, b); + return; } + + // Scan for right place to put into list. List + // is sorted by increasing addresses + FreeBlock* prev = _freelist; + FreeBlock* cur = _freelist->link(); + while(cur != NULL && cur < b) { + assert(prev < cur, "Freelist must be ordered"); + prev = cur; + cur = cur->link(); + } + assert((prev < b) && (cur == NULL || b < cur), "free-list must be ordered"); + insert_after(prev, b); } -// Search freelist for an entry on the list with the best fit -// Return NULL if no one was found +/** + * 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, bool is_critical) { - FreeBlock *best_block = NULL; - FreeBlock *best_prev = NULL; - size_t best_length = 0; + FreeBlock* found_block = NULL; + FreeBlock* found_prev = NULL; + size_t found_length = 0; - // Search for smallest block which is bigger than length - FreeBlock *prev = NULL; - FreeBlock *cur = _freelist; + FreeBlock* prev = NULL; + FreeBlock* cur = _freelist; + const size_t critical_boundary = (size_t)high_boundary() - CodeCacheMinimumFreeSpace; + + // Search for first block that fits while(cur != NULL) { - size_t l = cur->length(); - if (l >= length && (best_block == NULL || best_length > l)) { - + if (cur->length() >= length) { // 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; - } + // Make sure the end of the allocation doesn't cross into the last part of the code heap. + if (!is_critical && (((size_t)cur + length) > critical_boundary)) { + // The freelist is sorted by address - if one fails, all consecutive will also fail. + break; } + // Remember block, its previous element, and its length + found_block = cur; + found_prev = prev; + found_length = found_block->length(); - // Remember best block, its previous element, and its length - best_block = cur; - best_prev = prev; - best_length = best_block->length(); + break; } - // Next element in list prev = cur; cur = cur->link(); } - if (best_block == NULL) { + if (found_block == NULL) { // None found return NULL; } - assert((best_prev == NULL && _freelist == best_block ) || - (best_prev != NULL && best_prev->link() == best_block), "sanity check"); - // Exact (or at least good enough) fit. Remove from list. // Don't leave anything on the freelist smaller than CodeCacheMinBlockLength. - if (best_length < length + CodeCacheMinBlockLength) { - length = best_length; - if (best_prev == NULL) { - assert(_freelist == best_block, "sanity check"); + if (found_length - length < CodeCacheMinBlockLength) { + _freelist_length--; + length = found_length; + if (found_prev == NULL) { + assert(_freelist == found_block, "sanity check"); _freelist = _freelist->link(); } else { + assert((found_prev->link() == found_block), "sanity check"); // Unmap element - best_prev->set_link(best_block->link()); + found_prev->set_link(found_block->link()); } } else { // Truncate block and return a pointer to the following block - best_block->set_length(best_length - length); - best_block = following_block(best_block); // Set used bit and length on new block - size_t beg = segment_for(best_block); + found_block->set_length(found_length - length); + found_block = following_block(found_block); + + size_t beg = segment_for(found_block); mark_segmap_as_used(beg, beg + length); - best_block->set_length(length); + found_block->set_length(length); } - best_block->set_used(); + found_block->set_used(); _freelist_segments -= length; - return best_block; + return found_block; } //---------------------------------------------------------------------------- @@ -471,33 +496,34 @@ tty->print_cr("The Heap"); } -#endif - void CodeHeap::verify() { - // Count the number of blocks on the freelist, and the amount of space - // represented. - int count = 0; - size_t len = 0; - for(FreeBlock* b = _freelist; b != NULL; b = b->link()) { - len += b->length(); - count++; - } - - // Verify that freelist contains the right amount of free space - // guarantee(len == _freelist_segments, "wrong freelist"); + if (VerifyCodeCache) { + size_t len = 0; + int count = 0; + for(FreeBlock* b = _freelist; b != NULL; b = b->link()) { + len += b->length(); + count++; + // Check if we have merged all free blocks + assert(merge_right(b) == false, "Missed merging opportunity"); + } + // Verify that freelist contains the right amount of free space + assert(len == _freelist_segments, "wrong freelist"); - // Verify that the number of free blocks is not out of hand. - static int free_block_threshold = 10000; - if (count > free_block_threshold) { - warning("CodeHeap: # of free blocks > %d", free_block_threshold); - // Double the warning limit - free_block_threshold *= 2; - } + for(HeapBlock* h = first_block(); h != NULL; h = next_block(h)) { + if (h->free()) count--; + } + // Verify that the freelist contains the same number of blocks + // than free blocks found on the full list. + assert(count == 0, "missing free blocks"); - // Verify that the freelist contains the same number of free blocks that is - // found on the full list. - for(HeapBlock *h = first_block(); h != NULL; h = next_block(h)) { - if (h->free()) count--; + // Verify that the number of free blocks is not out of hand. + static int free_block_threshold = 10000; + if (count > free_block_threshold) { + warning("CodeHeap: # of free blocks > %d", free_block_threshold); + // Double the warning limit + free_block_threshold *= 2; + } } - // guarantee(count == 0, "missing free blocks"); } + +#endif diff -r 141e27fa5a42 -r b6426873cb37 hotspot/src/share/vm/memory/heap.hpp --- a/hotspot/src/share/vm/memory/heap.hpp Thu Mar 06 14:35:26 2014 +0100 +++ b/hotspot/src/share/vm/memory/heap.hpp Fri Mar 07 07:42:40 2014 +0100 @@ -92,24 +92,28 @@ FreeBlock* _freelist; size_t _freelist_segments; // No. of segments in freelist + int _freelist_length; + + enum { free_sentinel = 0xFF }; // Helper functions 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; } + bool is_segment_unused(int val) const { return val == free_sentinel; } HeapBlock* block_at(size_t i) const { return (HeapBlock*)(_memory.low() + (i << _log2_segment_size)); } void mark_segmap_as_free(size_t beg, size_t end); void mark_segmap_as_used(size_t beg, size_t end); // Freelist management helpers - FreeBlock* following_block(FreeBlock *b); + FreeBlock* following_block(FreeBlock* b); void insert_after(FreeBlock* a, FreeBlock* b); - void merge_right (FreeBlock* a); + bool merge_right (FreeBlock* a); // Toplevel freelist management - void add_to_freelist(HeapBlock *b); + void add_to_freelist(HeapBlock* b); FreeBlock* search_freelist(size_t length, bool is_critical); // Iteration helpers @@ -120,20 +124,18 @@ // to perform additional actions on creation of executable code void on_code_mapping(char* base, size_t size); + void clear(); // clears all heap contents public: CodeHeap(); // Heap extents bool reserve(size_t reserved_size, size_t committed_size, size_t segment_size); - void release(); // releases all allocated memory bool expand_by(size_t size); // expands committed memory by size - void shrink_by(size_t size); // shrinks committed memory by size - void clear(); // clears all heap contents // Memory allocation void* allocate (size_t size, bool is_critical); // allocates a block of size or returns NULL - void deallocate(void* p); // deallocates a block + void deallocate(void* p); // deallocates a block // Attributes char* low_boundary() const { return _memory.low_boundary (); } @@ -141,12 +143,13 @@ 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 + 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 + size_t allocated_in_freelist() const { return _freelist_segments * CodeCacheSegmentSize; } + int freelist_length() const { return _freelist_length; } // number of elements in the freelist // returns the first block or NULL void* first() const { return next_free(first_block()); } @@ -156,6 +159,7 @@ // Statistics size_t capacity() const; size_t max_capacity() const; + int allocated_segments() const; size_t allocated_capacity() const; size_t unallocated_capacity() const { return max_capacity() - allocated_capacity(); } @@ -164,7 +168,7 @@ public: // Debugging - void verify(); + void verify() PRODUCT_RETURN; void print() PRODUCT_RETURN; }; diff -r 141e27fa5a42 -r b6426873cb37 hotspot/src/share/vm/runtime/arguments.cpp --- a/hotspot/src/share/vm/runtime/arguments.cpp Thu Mar 06 14:35:26 2014 +0100 +++ b/hotspot/src/share/vm/runtime/arguments.cpp Fri Mar 07 07:42:40 2014 +0100 @@ -2407,6 +2407,8 @@ status &= verify_interval(NmethodSweepFraction, 1, ReservedCodeCacheSize/K, "NmethodSweepFraction"); status &= verify_interval(NmethodSweepActivity, 0, 2000, "NmethodSweepActivity"); + status &= verify_interval(CodeCacheMinBlockLength, 1, 100, "CodeCacheMinBlockLength"); + status &= verify_interval(CodeCacheSegmentSize, 1, 1024, "CodeCacheSegmentSize"); // TieredCompilation needs at least 2 compiler threads. const int num_min_compiler_threads = (TieredCompilation && (TieredStopAtLevel >= CompLevel_full_optimization)) ? 2 : 1; diff -r 141e27fa5a42 -r b6426873cb37 hotspot/src/share/vm/runtime/globals.hpp --- a/hotspot/src/share/vm/runtime/globals.hpp Thu Mar 06 14:35:26 2014 +0100 +++ b/hotspot/src/share/vm/runtime/globals.hpp Fri Mar 07 07:42:40 2014 +0100 @@ -814,8 +814,8 @@ product(bool, PrintOopAddress, false, \ "Always print the location of the oop") \ \ - notproduct(bool, VerifyCodeCacheOften, false, \ - "Verify compiled-code cache often") \ + notproduct(bool, VerifyCodeCache, false, \ + "Verify code cache on memory allocation/deallocation") \ \ develop(bool, ZapDeadCompiledLocals, false, \ "Zap dead locals in compiler frames") \ @@ -3296,8 +3296,8 @@ "disable this feature") \ \ /* code cache parameters */ \ - /* ppc64 has large code-entry alignment. */ \ - develop(uintx, CodeCacheSegmentSize, 64 PPC64_ONLY(+64), \ + /* ppc64/tiered compilation has large code-entry alignment. */ \ + develop(uintx, CodeCacheSegmentSize, 64 PPC64_ONLY(+64) NOT_PPC64(TIERED_ONLY(+64)),\ "Code cache segment size (in bytes) - smallest unit of " \ "allocation") \ \