These classes are meant to replace OS::Ticks() and OS::TimeCurrentMillis(),
which are broken in several ways. The ElapsedTimer class implements a
stopwatch using TimeTicks::HighResNow() for high resolution, monotonic
timing.
Also fix the CpuProfile::GetStartTime() and CpuProfile::GetEndTime()
methods to actually return the time relative to the unix epoch as stated
in the documentation (previously that was relative to some arbitrary
point in time, i.e. boot time).
BUG=v8:2853
R=machenbach@chromium.org
Review URL: https://codereview.chromium.org/23469013
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16398 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
These classes are meant to replace OS::Ticks() and OS::TimeCurrentMillis(),
which are broken in several ways. The ElapsedTimer class implements a
stopwatch using TimeTicks::HighResNow() for high resolution, monotonic
timing.
Also fix the CpuProfile::GetStartTime() and CpuProfile::GetEndTime()
methods to actually return the time relative to the unix epoch as stated
in the documentation (previously that was relative to some arbitrary
point in time, i.e. boot time).
BUG=v8:2853
R=machenbach@chromium.org, yurys@chromium.org
Review URL: https://codereview.chromium.org/23295034
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16388 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
No need to duplicate OS::NumberOfCores() for every POSIX platform.
No need to duplicate OS::Sleep() for every POSIX platform.
No need to duplicate OS::Abort() and OS::DebugBreak() for every POSIX platform.
No need to duplicate OS::Free() for every POSIX platform.
Move #ifdef'd OS::ProtectCode() and OS::Guard() to platform-posix.cc.
No need to duplicate OS::AllocateAlignment() for every POSIX platform.
No need to duplicate OS::PostSetUp() for every POSIX platform.
R=svenpanne@chromium.org
Review URL: https://codereview.chromium.org/20014005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15820 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This is a first step to having profiler sampler implementation in one file with platform capabilities guarded with #ifdef. Otherwise we have very similar implementations scattered over platform-*.cc files which makes it hard to see differences and make changes.
The next steps will be to merge win32, Mac OS X and Cygwin implementations into sampler.cc They suspend profiled thread instead of sending a signal but apart from that the logic is pretty much the same. Then I'm going to move sampler-related code from log.* into sampler.*
BUG=None
Review URL: https://codereview.chromium.org/13852005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14265 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The new test checks full CPU profiling cycle: using public
V8 API it starts profiling, executes a script, stops profiling
and analyzes collected profile to check that its top-down
tree has expected strutcture. The script that is being profiled
is guaranteed to run > 200ms to make sure enough samples
are collected.
To avoid possible flakiness due to non-deterministic time required
to start new thread on varios OSs when Sampler and ProfilerEventsProcessor
threads are being started the main thread is blocked until the threads
are running.
Also I removed the heuristic in profile-generator.cc where we try
to figure out if the value on top of the sampled stack is return address
of some frameless stub invocation. The code periodically gives false positive
with the new test ending up in an extra node in the collected cpu profile.
After discussion with jkummerow@ we concluded that the logic is too fragile
and that we can address frameless stub invocations in a more reliable way
later should they have a noticeable effect on cpu profiling.
BUG=None
Review URL: https://codereview.chromium.org/13627002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14205 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The patch is based on the previous one that was rolled out: https://code.google.com/p/v8/source/detail?r=12985
On Linux sampling for CPU profiler is initiated on the profiler event processor thread, other platforms to follow.
CPU profiler continues to use SamplingCircularQueue, we will replave it with a single sample buffer when Mac and Win ports support profiling on the event processing thread.
When --prof option is specified profiling is initiated either on the profiler event processor thread if CPU profiler is on or on the SignalSender thread as it used to if no CPU profiles are being collected.
ProfilerEventsProcessor::ProcessEventsAndDoSample now waits in a tight loop, processing collected samples until sampling interval expires. To save CPU resources I'm planning to change that to use nanosleep as only one sample is expected in the queue at any point.
BUG=v8:2364
Review URL: https://codereview.chromium.org/12321046
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13735 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- perform CPU profiler sampling in the sampler thread as we used to;
- skip sampling in the sampling thread if processing thread is running;
- only install SIGPROF handler when CPU profiling is enabled.
BUG=v8:2364
Review URL: https://codereview.chromium.org/11231002
Patch from Sergey Rogulenko <rogulenko@google.com> and Andrey Kosyakov <caseq@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12985 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The patch introduces CommittedPhysicalMemory function to
the Heap class that reports committed *physical* memory acquired
for the heap from the OS.
It is important because some OSes may defer actual committment on e.g.
first access to the region.
So reporting just plain committed size led to various weird artifacts
like showing V8 allocated memory higher than the whole process
private size.
BUG=v8:2191
Review URL: https://codereview.chromium.org/11066118
Patch from Alexei Filippov <alph@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12793 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The patch introduces CommittedPhysicalMemory function to the Heap class
that reports committed *physical* memory acquired from the OS.
It is important because some OSes may postpone actual commitment on e.g.
first access to the previously committed region.
So reporting just plain committed size led to various weird artifacts
like DevTools showing V8 allocated memory higher than the whole process
private size.
BUG=v8:2191
Review URL: https://codereview.chromium.org/10961042
Patch from Alexei Filippov <alph@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12625 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This CL:
- Adds a new trait parameter to LazyInstance to let it initialize the instance
without paying the cost of atomic operations (which are expensive on Mac).
This only works for users who don't care about thread-safety and this is now
the default initialization trait used by LazyInstance in v8.
- Reverts the changes that were made in r11010 in isolate.{cc,h}. That lets
Isolate's accessors be as cheap as they were before (but adds one static initializer).
- Adds OS::PostSetup() used to initialize the math functions which depend on CPU features.
That lets the math functions get rid of CallOnce().
BUG=118686
Review URL: https://chromiumcodereview.appspot.com/9873023
Patch from Philippe Liard <pliard@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11198 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change includes two CLs by pliard@chromium.org:
1. http://codereview.chromium.org/9447052/ (Add CallOnce() and simple LazyInstance implementation):
Note that this implementation of LazyInstance does not handle global destructors (i.e. the lazy instances are never deleted).
This CL was initially reviewed on codereview.appspot.com:
http://codereview.appspot.com/5687064/
2. http://codereview.chromium.org/9455088/ (Remove static initializers in v8):
This CL depends on CL 9447052 (adding CallOnce and LazyInstance).
It is based on a patch sent by Digit.
With this patch applied, we have only one static initializer left (in atomicops_internals_x86_gcc.cc). This static initializer populates a structure used by x86 atomic operations. It seems that we can hardly remove it. If possible, it will be removed in a next CL.
This CL also modifies the presubmit script to check the number of static initializers.
BUG=v8:1859
Review URL: https://chromiumcodereview.appspot.com/9666052
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11010 ce2b1a6d-e550-0410-aec6-3dcde31c8c00