a mark-sweep. We have a soft limit on old space size, which is designed to
trigger an old-space collection when we hit it. Unfortunately although the
soft limit had already triggered an old space collection, the soft limit was
preventing objects from new space from being promoted. For every promotion
candidate we were checking 3 different ways to allocate in old space before
giving up and putting the object in the other semispace. This change allows
the promoted objects to go to old space and also makes us more eager to
sweep a page before trying other ways to find space for an object.
Review URL: http://codereview.chromium.org/8748005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10092 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Our Heap::FreeQueuedChunks generates fake inner chunks in large object
pages queued for freeing, so that StoreBuffer::Filter can recognize them
as pages to be freed. This also relies on MemoryChunk::Contains to work
properly, which is why the size field needs to be initialized as well.
R=vegorov@chromium.org
BUG=v8:1817
TEST=mozilla/js1_5/Regress/regress-360969-05
Review URL: http://codereview.chromium.org/8536009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9964 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Heap::Shrink is called from EnsureFromSpaceIsCommitted at the very start of the GC. At this moment live bytes counts on pages are in inconsistent states. Some pages might have been already swept but have not been yet reached by an incremental marker (or incremental marker is not in progress) and have live bytes count set to 0. Thus we can't rely only on LiveBytes to determine which pages can be released to the OS.
R=mstarzinger@chromium.org
BUG=100414
Review URL: http://codereview.chromium.org/8507038
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9953 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
All slots that were recorded on these objects during incremental marking should be ignored as they are no longer valid.
To filter such invalidated slots out during slots buffers iteration we set all markbits under the invalidated code object to 1 after the code space was swept and before slots buffers are processed.
R=erik.corry@gmail.com
BUG=v8:1713
TEST=test/mjsunit/regress/regress-1713.js
Review URL: http://codereview.chromium.org/7983045
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9402 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The "live bytes" count is *really* a "marked black" count - i.e., the count of bytes *known* to be live.
Fix aggravating bug on X64 where assembler code used a value that was off
by a factor of 2^31.
Ensure that sweeping clears live-bytes. Added other missing increments.
Added print statements to trace live-byte modifications, under a flag.
Still a few cases of undercounting left.
(New issue to merge from GC branch to bleeding_edge)
Review URL: http://codereview.chromium.org/7970009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9338 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Passing a value of type Executability to a function expecting a bool worked only
by accident (because of the order of values in the enum). But using boolean
parameters is often a bad idea, anyway, so we use Executability directly.
Just another example why implicit type conversions in C++ are a bad idea... :-P
Review URL: http://codereview.chromium.org/7753001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9013 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The preprocessor defines ENABLE_LOGGING_AND_PROFILING and ENABLE_VMSTATE_TRACKING has been removed as these where required to be turned on for Crankshaft to work. To re-enable reducing the binary size by leaving out heap and CPU profiler a new set of defines needs to be created.
R=ager@chromium.org
BUG=v8:1271
TEST=all
Review URL: http://codereview.chromium.org//7350014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8622 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The object's space in Page starts after Page header and is aligned to kMapAlignment which is 32 bytes on 32-bit and 8 bytes on 64-bit.
In case of 64-bit target, the current page header size is exactly 32 bytes so we get the code magically aligned at 32 bytes but it is better to have a separate CODE_POINTER_ALIGN macro to make sure the object space in Page is aligned properly for both maps and code.
There could be a small waste of bytes sometimes (since both Page header and Code header sizes are aligned separately) but it seems the optimal one would involve cross-dependencies between .h files and not clear if it's worth it.
This is a back-port from Isolates branch.
Review URL: http://codereview.chromium.org/3461021
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5526 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Allows the host application to provide a mechanism for notification and custom logging through a callback (set through the API V8::AddMemoryAllocationCallback and removed through V8::RemoveMemoryAllocationCallback), when V8 allocates ro frees memory.
This replaces the current histogram data "V8.ExecutableMemoryMax" by allowing usage data to be logged by the application as required rather than always through V8.
BUG=http://crbug.com/54222
TEST=Set the callback function with the API and cause V8 to allocate memory.
Patch by Paul Mehta <pmehta@chromium.org>
Review URL: http://codereview.chromium.org/3329006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5403 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
That could improve chances for commit success as currently,
if we moved free pages out of order, we cannot shrink spaces.
However, when we experience problems commiting from space back, we should
use most of resources at our disposal.
Also get rid of currently unused parameter to DeallocateFunction.
Review URL: http://codereview.chromium.org/3260001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5372 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
the code object's instructions.
This allows us to find a code object using just the pc. This approach
uses a cache (PcToCodeCache) to make sure we don't continuously have
to iterate heap pages.
This change eliminates the need for cooking and uncooking of stack frames.
Review URL: http://codereview.chromium.org/3226014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5369 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- New сardmarking write barrier handles large objects and normal objects in a similar fashion (no more additional space for pointer tracking is required, no conditional branches in WB code).
- Changes to enable oldspaces iteration without maps decoding:
-- layout change for FixedArrays: length is stored as a smis (initial patch by
Kevin Millikin)
-- layout change for SharedFunctionInfo: integer fields are stored as smi on
arm, ia32 and rearranged on x64.
-- layout change for String: meaning of LSB bit is fliped (1 now means hash not
computed); on x64 padding is added.
-- layout of maps is _not_ changed. Map space is currently iterated in a special
way.
Review URL: http://codereview.chromium.org/2144006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4715 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
-- layout change for FixedArrays: length is stored as a smis (initial patch by Kevin Millikin)
-- layout change for SharedFunctionInfo: integer fields are stored as smi on arm, ia32 and rearranged on x64.
-- layout change for String: meaning of LSB bit is fliped (1 now means hash not computed); on x64 padding is added.
-- layout of maps is _not_ changed. Map space is currently iterated in a special way.
- Cardmarking write barrier. New barrier handles large objects and normal objects in a similar fashion (no more additional space for pointer tracking is required, no conditional branches in WB code).
Review URL: http://codereview.chromium.org/2101002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4685 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- RelinkPageListInChunkOrder might relink unused pages into the middle of a sequence of used pages. Filler objects should be placed at the beginning of such unused pages otherwise generic iterators (e.g. HeapObjectIterator) would not handle them correctly.
- ObjectAreaEnd() should not be used as an allocation limit for pages from FixedSpace. Pages in such spaces do not use top page_extra_ bytes of object area.
TBR=ager@chromium.org
Review URL: http://codereview.chromium.org/1700005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4476 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Always invoke HeapObjectIterator::has_next() before invoking HeapObjectIterator::next().
This is necessary as ::has_next() has an important side-effect of going to the next
page when current page is exhausted.
And to find if pointers are encodable use more precise data---top of map space, not a number
of pages, as pages might stay in map space due to chunking.
Review URL: http://codereview.chromium.org/552066
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3672 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
for partial snapshots. After reserving space we can be sure that allocations
will happen linearly (no GCs and no free-list allocation). This change also
contains the start of the partial snapshot support, which, however is not yet
completed or tested.
Review URL: http://codereview.chromium.org/545026
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3584 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
On 32-bit the maps are now aligned on a 32-byte boundary in order to encode more maps during compacting GC. The actual size of a map on 32-bit is 28 bytes making this change waste 4 bytes per map.
On 64-bit the encoding for compacting GC is now using more than 32-bits and the maps here are still pointer size aligned. The actual size of a map on 64-bit is 48 bytes and this change does not intruduce any waste.
My choice of 16 bits for kMapPageIndexBits for 64-bit should give the same maximum number of pages (8K) for map space. As maps on 64-bit are larger than on 32-bit the total number of maps on 64-bit will be smaller than on 32-bit. We could consider raising this to 17 or 18.
I moved the kPageSizeBits to globals.h as the calculation of the encoding really depended on this.
There are still an #ifdef/#endif in objects.h and this constant could be moved to globaks.h as well, but I kept it together with the related constants.
All the tests run in debug mode with additional options --gc-global --always-compact as well (except for a few tests on which also fails before this change when run with --gc-global --always-compact).
BUG=http://code.google.com/p/v8/issues/detail?id=524
BUG=http://crbug.com/29428
TEST=test/mjsunit/regress/regress-524.js
Review URL: http://codereview.chromium.org/504026
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3481 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
