The profile is taken together with constructors profile. In theory, it
should represent a complete heap graph. However, this takes a lot of memory,
so it is reduced to a more compact, but still useful form. Namely:
- objects are aggregated by their constructors, except for Array and Object
instances, that are too hetereogeneous;
- for Arrays and Objects, initially every instance is concerned, but then
they are grouped together based on their retainer graph paths similarity (e.g.
if two objects has the same retainer, they are considered equal);
Review URL: http://codereview.chromium.org/200132
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2903 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The main piece of this change was to add support for break on return for ARM. On ARM the normal js function return consist of the following code sequence.
mov sp, fp
ldmia sp!, {fp, lr}
add sp, sp, #4
bx lr
to a call to the debug break return entry code using the following code sequence
mov lr, pc
ldr pc, [pc, #-4]
<debug break return entry code entry point address>
bktp 0
The values of Assembler::kPatchReturnSequenceLength and Assembler::kPatchReturnSequenceLength are somewhat misleading, but they fit the current use in the debugger. Also Assembler::kPatchReturnSequenceLength is used in the IC code as well (for something which is not related to return sequences at all). I will change that in a separate changelist.
For the debugger to work also added recording of the return sequence in the relocation info and handling of source position recording when a function ends with a return statement.
Used the constant kInstrSize instead of sizeof(Instr).
Passes all debugger tests on both simulator and hardware (only release mode tested on hardware).
Review URL: http://codereview.chromium.org/199075
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2879 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The SCons build now supports building for 64-bit Windows. This still requires that the SCons build is passed an env parameter containing the PATH and LIB for the 64-bit build as SCons autodetects the 32-bit environment.
Lowered the warning level for the 64-bit build temporarily.
Added a verbose option to SCons to display the startup banner for the Microsoft Visual C++ tools.
Review URL: http://codereview.chromium.org/174605
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2774 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
I'm planning to use it in DevTools heap profiler. It is a common scenario in debugging memory leaks to enforce GC, then perform an operation, then enforce GC again to check for non-collected (that is, leaked) objects. Using the existing GC extension isn't possible because it doesn't exposed in the normal operation mode of Chromium.
Review URL: http://codereview.chromium.org/159787
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2619 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
It is activated with '--log-gc' flag.
JS object size is calculated as its size + size of 'properties' and 'elements' arrays, if they are non-empty. This doesn't take maps, strings, heap numbers, and other shared objects into account.
As Soeren suggested, I've moved ZoneSplayTree from jsregexp to zone, and removed now empty jsregexp-inl header file.
Review URL: http://codereview.chromium.org/159504
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2570 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
I found two causes of flakinness:
- SIGPROF signal isn't delivered to a process;
- Profiler thread (the one that retrieves tick events from
the queue and writes to log) doesn't get a CPU;
Both are fixed.
The script from bug description with run count increased to 200 runs without any test failures.
OS X and Windows are unaffected because they don't use signals mechanism.
BUG=http://code.google.com/p/v8/issues/detail?id=410
TEST=see bug description
Review URL: http://codereview.chromium.org/159406
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2547 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
If V8 is holding on to a lot of external memory, we attempt to clean
it up even if we do not get an allocation failure. Since tiny V8
objects can hold on to a lot of external memory, we might run out of
external memory while waiting for a normal allocation failure.
Review URL: http://codereview.chromium.org/155916
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2519 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Remove the check for deleted properties in the global load inline cache if the property is known to be read only.
Propegate the in loop flag for the global call inline cache.
Changed the propagation of the code flags in the call stub compiler to compute these the same way for all types of call stubs and assert that the flags for the generated code is the same as those used for the cache lookup.
Addressed a few comments from previous review in test-api.cc.
Review URL: http://codereview.chromium.org/150101
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2308 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
* Fix incorrect signedness in disassembly of umull/mull on ARM.
* Fix incorrect register order in disassembly of umull/mull.
* Fix incorrect assembly of umull on ARM.
* Remove retroactively obsoleted restriction on choice of
registers in mul instructions on ARM.
Review URL: http://codereview.chromium.org/150002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2292 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Code addresses are now written as an offset from the previous address for ticks, code move and delete events. Employed backreference and RLE compression for code move and delete events. This gives additional 30% log size reduction for benchmarks run w/o snapshot.
Overall compression results (compared with the revision of V8 having no compression):
- V8: 70% size reduction for benchmarks run w/o snapshot (for reference, gzip gives 87%)
- Chromium: 65% size reduction for public html version of benchmarks (v4) (for reference, gzip gives 90%)
The one obvious opportunity for improving compression results in Chromium is to compress URLs of scripts.
Review URL: http://codereview.chromium.org/125114
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2162 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Two techniques are involved:
- compress repeated line ends (common stack beginnings) by using back references;
- do RLE compression of repeated tick events.
This gives only 5% size reduction on benchmarks run, but this is because tick events are only comprise 10% of file size. Under Chromium winnings are bigger because long repeated samples of idleness are now compressed into a single line.
Tickprocessor will be updated in the next patch.
Review URL: http://codereview.chromium.org/123012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2147 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
interceptors and dont-delete attributes.
Minor change to the behavior of eval: throw exception when calling
eval in a context for which the global has been detached. This
matches the behavior of both Firefox and Safari post navigation in the
browser.
Review URL: http://codereview.chromium.org/118374
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2118 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
submitted in revisions 2093, 2094, 2099, and 2106.
There's no evidence that supports that these changes
should be the cause of the unexplained performance
regressions on the intl2 and DHTML page cyclers.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2109 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The problem was I incorrectly treated NULL result as failure to fetch
a property with a getter. However, if getter returns zero, it is
manifested as NULL pointer (see added test case).
Good news: that gives another boost as before this CL if getter returned
0, I did another slow lookup.
Review URL: http://codereview.chromium.org/119172
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2106 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
My assumption that log initialization happens somewhere near the stack's bottom is true for V8's sample shell but isn't true for Chromium, causing many otherwise valid stack addresses to be thrown out. The solution proposed is to save stack pointer value for the outermost JS function in ThreadLocalTop similar to c_entry_fp.
Implemented only for IA-32. Currently I'm not dealing with profiling on ARM and x86-64 anyway.
Review URL: http://codereview.chromium.org/112082
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2086 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
* Running "system" JavaScript with the debug break flag active leads to slow running code while waiting for the break in non "system" JavaScript (one exception to this it is to try to avoid breaks in the clear mirror cache JavaScript code called when leaving the debugger).
* If this happens while processing RegExp running in native code an infinite loop is created as the stack guard handler for RegExp does not move execution forward
Fixed a GC bug in the interrupt handling for RegExp running in native code.
Added test of debug break while in debug message handler callback and debug break while executing a RegExp.
Review URL: http://codereview.chromium.org/115262
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2074 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
When profiler's memory buffer is filled up, profiling is stopped and it is ensured that the last record in the buffer is "profiler,\"pause\"" thus making the end of profiling session explicit. Otherwise DevTools Profiler would need to guess whether the current profiling session has been stopped.
Tested with Chromium.
Review URL: http://codereview.chromium.org/115859
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2072 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The goal of this change is to allow longer profiling sessions and preserve memory when profiler isn't started. The buffer starts with 64K and grows until it reaches the upper limit, which is currently set to 50MB --- according to my evaluations, this is enough for at least 20 minutes of GMail profiling. As we're planning to introduce compression for the profiler log, this time boundary will be significantly increased soon.
To make possible unit testing of the new component, I've factored out Logger's utility classes into a separate source file: log-utils.h/cc. Log and LogMessageBuilder are moved there from log.cc without any semantical changes.
Review URL: http://codereview.chromium.org/115814
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2067 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
