The problem is other array may have holes, for example
when fixed array comes from JSArray (in case of named interceptor).
If that would prove to be a performance problem, we could
pass an additional argument into UnionOfKeys to hold actual length.
Review URL: http://codereview.chromium.org/3595013
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5591 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
during snapshot size optimization.
Sorry, now I figured out that the diff implementation itself was also
incorrect. Reachable nodes must be filtered from the beginning,
otherwise, an object that is already disconnected, but not discarded
yet, will not appear as a deleted (thankfully, this bug for some
reason had appeared on the x64 port.)
BUG=868
TEST=HeapSnapshotRootPreservedAfterSorting
Review URL: http://codereview.chromium.org/3531005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5570 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Finally sovles the problem that r5342 attempted to solve.
When adding a stub to a map's code cache we need to make
sure that this map is not used by object that do not need
this stub.
Existing solution had 2 flaws:
1. It checked that the map is cached by asking the current context.
If the object escaped into another context then NormalizedMapCache::Contains
returns false negative.
2. If a map gets evicted from the cache we should not try to modify it
even though Contains returns false.
This patch implements much less fragile solution of the same problem:
A map now has a flag (is_shared) that is set once the map is added
to a cache, stays set even after the cache eviction, and is cleared
if the object goes back to fast mode.
Added a regression test.
Review URL: http://codereview.chromium.org/3472006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5518 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The number of inobject properties used to be derived from the number
of this property assignments in the constructor (and increased by 2 to
allow for properties added later). This very often leads to wasted inobject
slots.
This patch reclaims some of the unused inobject space by the following method:
- for each constructor function the first several objects are allocated using the initial
("generous) instance size estimation (this is called 'tracking phase').
- during the tracking phase map transitions are tracked and actual property counts are collected.
- at the end of the tracking phase instance sizes in the maps are decreased if necessary
(starting with the function's initial map and traversing the transition tree).
- all further allocation use more realistic instance size estimation.
Shrinking generously allocated objects without costly heap traversal is made possible
by initializing their inobject properties with one_pointer_filler_map (instead of undefined).
The initial slack for the generous allocation is increased from 2 to 6 which really helps some tests.
Review URL: http://codereview.chromium.org/3329019
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5510 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
It turns out they were filtered out. But when I unfiltered them, I
discovered another issue: when DevTools run, regexp literals get
recompiled each time they called (looks like this is concerned with
switching to full compiler), so I ended up having multiple entries for
the same regexp. To fix this, I changed the way of how code entries
equivalence is considered.
BUG=crbug/55999
TEST=cctest/test-profile-generator/ProfileNodeFindOrAddChildForSameFunction
(the test isn't for the whole issue, but rather for equivalence testing)
Review URL: http://codereview.chromium.org/3426008
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5492 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
When running profiling in debug mode, several assertions in frame
iterators that are undoubtedly useful when iterator is started from a
VM thread in a known "good" state, may fail when running over a stack
of a suspended VM thread. This patch makes SafeStackFrameIterator
to proactively check addresses and bail out from iteration early,
before an assertion will be triggered.
BUG=crbug/55565
Review URL: http://codereview.chromium.org/3436006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5467 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
to avoid storing serialized snapshot on VM, instead it is emitted
using output stream interface.
The size of JSON emitted is roughly equal to used heap size
(when stored as an ASCII string).
Now a whole heap snapshot can be serialized and transmitted outside
VM. This makes possible:
- implementing non-async UI for heap snapshots inspection;
- storing heap snapshots for further inspection;
- remote profiling (we can even implement a snapshotting mode
where a snapshot isn't even stored in VM, only transmitted --
good for mobile devices);
- creating tools for outside heap snapshots processing, e.g.
converting to HPROF.
Review URL: http://codereview.chromium.org/3311028
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5450 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
