An attempt to retrieve security context for a function may fail if the
destination heap space is in an incomplete state. To fix this, we only
record unknown functions discovered at GC object moves, and then
register them after GC completes.
BUG=crbug/59627
Review URL: http://codereview.chromium.org/3763012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5667 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Since 2.6.31 perf_events interface has been available in the
kernel. There's a nice tool called "perf" (linux-2.6/tools/perf) that
uses this interface and provides capabilities similar to oprofile. The
simplest form of its usage is just dumping the raw log (trace) of
events generated by the kernel. In this patch I'm adding a script
(tools/ll_prof.py) to build profiles based on perf trace and our code
log. All the heavy-lifting is done by perf. Compared to oprofile agent
this approach does not require recompilation and supports code moving
garbage collections.
Expected usage is documented in the ll_prof's help. Basically one
should run V8 under perf passing --ll-prof flag and then the produced
logs can be analyzed by tools/ll_prof.py.
The new --ll-prof flag enables logging of generated code object
locations and names (like --log-code), and also of their bodies, which
can be later disassembled and annotated by the script.
Review URL: http://codereview.chromium.org/3831002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5663 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The cause for missing functions is that some of them are created
from compiled code (see FastNewClosureStub), and thus not get
registered in profiler's code map.
My solution is to hook on GC visitor to provide JS functions
addresses to profiler, only if it is enabled.
BUG=858
TEST=
Review URL: http://codereview.chromium.org/3417019
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5523 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The simple formula "ms = ticks * sampler_interval" doesn't work,
because e.g. on Linux, the actual sampling rate can be 5 times
lower than the one set up in the code. To calculate actual sampling
rate, current time is periodically queried and processed along with
actual sampling ticks count.
Review URL: http://codereview.chromium.org/1539038
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4427 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This is to make possible enabling usage of the new profiling subsystem
in Chromium without much hassle. The idea is pretty simple: unless the
new profiling API is used, all works as usual, as soon as Chromium
starts to use the new API, it will work too.
Review URL: http://codereview.chromium.org/1635005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4382 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In browser (DevTools) mode, only non-native JS code and callbacks are reported.
Also, added "(garbage collector)" entry which accumulates samples count in GC state.
Trying to display "(compiler)" and "(external)" only brings confusion,
because it ends up in displaying scripts code under "(compiler)" node, and DOM
event handlers under "(external)" node, which looks weird.
Review URL: http://codereview.chromium.org/1523015
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4357 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- when logging 'open-tag' / 'close-tag' events, don't depend on
FLAG_log (as it may be not enabled, e.g. in Chromium);
- PauseProfiler / ResumeProfiler were supposing that they
use 'is_logging_' var exclusively, thus preventing any
other logging that may be turned on for diagnostic purposes.
Review URL: http://codereview.chromium.org/661246
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3986 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change allows to associate integer tags with blocks of profiler
log events, and repeat calls to 'ResumeProfiler' / 'PauseProfiler' in
order to establsh nested (not necessary properly nested) blocks. By
supporting this, we will be able to match WebInspector's CPU profiler
abilities in DevTools.
I also refactored some testing code.
Review URL: http://codereview.chromium.org/619004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3889 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The problem appeared due to a fact that stubs doesn't create a stack
frame, reusing the stack frame of the caller function. When building
stack traces, the current function is retrieved from PC, and its
callees are retrieved by traversing the stack backwards. Thus, for
stubs, the stub itself was discovered via PC, and then stub's caller's
caller was retrieved from stack.
To fix this problem, a pointer to JSFunction object is now captured
from the topmost stack frame, and is saved into stack trace log
record. Then a simple heuristics is applied whether a referred
function should be added to decoded stack, or not, to avoid reporting
the same function twice (from PC and from the pointer.)
BUG=553
TEST=added to mjsunit/tools/tickprocessor
Review URL: http://codereview.chromium.org/546089
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3673 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
As this is only needed for internal profiling (not for DevTools),
the following approach had been chosen:
- during snapshot creation, positions of serialized objects inside
a snapshot are logged;
- then during V8 initialization, positions of deserealized objects
are logged;
- those positions are used for retrieving code objects names from
snapshot creation log, which needs to be supplied to tick processor
script.
Positions logging is controlled with the new flag: --log_snapshot_positions.
This flag is turned off by default, and this adds no startup penalty.
To plug this fix to Golem, the following actions are needed:
- logs created using 'mksnapshot' need to be stored along with VM images;
- tick processor script needs to be run with '--snapshot-log=...' cmdline
argument.
BUG=571
Review URL: http://codereview.chromium.org/551062
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3635 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This is needed to show calls to DOM in CPU profiles. I can think
of a better approach like adding specific functions into V8 API
for explicitly providing callback names and modifying bindings codegen
appropriately. My plan is as follows:
- submit this CL;
- implement anything I need to process log data and display DOM
calls in profiles;
- think again about adding specific functions and modifying bindings
codegen.
BUG=http://code.google.com/p/chromium/issues/detail?id=27613
Review URL: http://codereview.chromium.org/402100
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3340 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Turned on with '--log-producers' flag, also needs '--noinline-new' (this is temporarily), '--log-code', '--log-gc'. Not all allocations are traced (I'm investigating.)
Stacks are stored using weak handles. Thus, when an object is collected, its allocation stack is deleted.
Review URL: http://codereview.chromium.org/267077
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3069 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
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
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
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
This is a trivial per-row compression:
- short aliases are introduced for events and code creation tags;
- in tick events, offsets are used instead of absolute addresses;
- removed 'code-allocation' event, as it seems not used.
The first two options are depend on the new flag: 'compress-log', which is off by default.
On benchmarks run w/o snapshot, this gives 45% log size reduction.
Review URL: http://codereview.chromium.org/119304
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2122 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
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
This issue was raised by Brett Wilson while reviewing my changelist for readability. Craig Silverstein (one of C++ SG maintainers) confirmed that we should declare one namespace per line. Our way of namespaces closing seems not violating style guides (there is no clear agreement on it), so I left it intact.
Review URL: http://codereview.chromium.org/115756
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2038 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This is intended to be used with Chromium. When in resource-saving mode, profiler doesn't consume any resources (sampler and logging is off) until resumed. Then again, when profiler is paused, sampling and logging are turned off.
Tested under Linux and Windows. Also have done preliminary testing with Chromium.
Review URL: http://codereview.chromium.org/113762
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2036 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The goal is to make possible having --prof flag always enabled in Chromium. Currently we can't do this because --prof causes compiler and gc to log code creations / moves / deletes which aren't needed until we start profiling. With LogCompiledFunctions it will be possible not to log anything until we start profiling. When started, the current map of compiled functions will be logged and compiler / gc logging will be enabled to update current state. When profling is stopped, logging will be turned off again.
Funny that testing code is actually much longer and complex than function code.
Review URL: http://codereview.chromium.org/112036
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2009 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This will enable reading profiler log in Chrome. The current implementation of memory buffer is trivial (fixed size buffer, no memory recycling) but enough to start end-to-end DevTools Profiler implementation. Later it will be enhanced.
Review URL: http://codereview.chromium.org/108011
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1870 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- String traversal test data (now in a zone)
- Debug message thread (now joined on exit)
- Threading test threads (now joined on exit)
- Changed message tests framework to cope with valgrind
Also, fixed a bug where we'd try to delete stack-allocated objects
when tearing down v8. Good times.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1622 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
JavaScriptFrameIterator is templatized on the iterator type and renamed to JavaScriptFrameIteratorTemp.
The original JSFI is now a typedef for JavaScriptFrameIteratorTemp<StackFrameIterator>. Because of templatizing, JSFI code is moved to frames-inl.h
StackTraceFrameIterator moved to frames.*
Implemented SafeStackFrameIterator which wraps StackFrameIterator and have the same interface. It performs additional checks of stack addresses prior to delegating to StackFrameIterator. SafeSFI is used in an another specialization of JavaScriptFrameIteratorTemp template to perform safe JS frames iteration on sampler ticks.
I haven't took an advantage of having multiple stack frames in tickprocessor yet.
Review URL: http://codereview.chromium.org/39009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1404 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change introduces a log message builder which builds the log message in a static string buffer instead of formatting the log message through fprintf. Currently this message can only be written to a file afterwards.
Changed the code related events to use the log message builder.
Review URL: http://codereview.chromium.org/20406
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1284 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Thus, instead of the following profiler records:
1.5% 1.5% LazyCompile: <anonymous>
we'll now have these:
1.5% 1.5% LazyCompile: <anonymous> richards.js:309
Basically, I translated two functions from messages.js into C++.
In the next CL I will update messages.js to use added native functions.
Review URL: http://codereview.chromium.org/19537
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1216 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
of the generated code. These can be used by the profiler to
categorize the ticks that occur within generated code and thereby show
more detailed information about where time is spent in generated code.
For instance, this is what the profiler displayed for a simple regexp
benchmark with irregexp-native before:
[JavaScript]:
total nonlib name
87.2% 87.2% RegExp: (?:\w*\W+)*
This is what we can display now:
[JavaScript]:
total nonlib name
87.2% 87.2% RegExp: (?:\w*\W+)*
- 53.0% 56.7% BranchOrBacktrack
- 14.9% 59.8% CheckCharacterLT
- 13.7% 20.4% CheckStackLimit
- 6.7% 6.7% SafeCall
- 2.7% 7.0% CheckCharacterGT
- 2.4% 2.4% SafeReturn
- 2.1% 2.1% LoadCurrentCharacter
- 1.8% 1.8% PushRegister
- 0.9% 0.9% PopRegister
- 0.9% 0.9% AdvanceRegister
- 0.3% 0.3% PopCurrentPosition
- 0.3% 0.3% CheckGreedyLoop
- 0.0% 20.4% PushBacktrack
- 0.0% 22.3% CheckCharacter
- 0.0% 2.4% IfRegisterLT
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1010 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- Changed the structure of regexp objects from having two internal
fields to having a single field containing a fixed array, since it's
easier to store the whole fixed array in the cache.
- Move printing of the command to after printing std{err,out} in the
compact progress indicators in the test framework.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@579 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
escape commas.
- Fixed issue with block-comparing unaligned strings on arm.
- Added short documentation to one of the Persistent constructors.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@554 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Fixed the handling of '>' and '<=' to use right-to-left conversion and left-to-right evaluation as specified by ECMA-262.
Fixed a branch elimination bug on the ARM platform where incorrect code was generated because of overly aggressive branch elimination.
Improved performance of code that repeatedly assigns the same function to the same property of different objects with the same map.
Untangled DEBUG and ENABLE_DISASSEMBLER defines. The disassembler no longer expects DEBUG to be defined.
Added platform-nullos.cc to serve as the basis for new platform implementations.
git-svn-id: http://v8.googlecode.com/svn/trunk@9 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Added a few samples and support for building them. The samples include a simple shell that can be used to benchmark and test V8.
Changed V8::GetVersion to return the version as a string.
Added source for lazily loaded scripts to snapshots and made serialization non-destructive.
Improved ARM support by fixing the write barrier code to use aligned loads and stores and by removing premature locals optimization that relied on broken support for callee-saved registers (removed).
Refactored the code for marking live objects during garbage collection and the code for allocating objects in paged spaces. Introduced an abstraction for the map word of a heap-allocated object and changed the memory allocator to allocate executable memory only for spaces that may contain code objects.
Moved StringBuilder to utils.h and ScopedLock to platform.h, where they can be used by debugging and logging modules. Added thread-safe message queues for dealing with debugger events.
Fixed the source code reported by toString for certain builtin empty functions and made sure that the prototype property of a function is enumerable.
Improved performance of converting values to condition flags in generated code.
Merged disassembler-{arch} files.
git-svn-id: http://v8.googlecode.com/svn/trunk@8 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
