Profiler Domain
Methods
Profiler.disable #
Profiler.getBestEffortCoverage #
Collect coverage data for the current isolate. The coverage data may be incomplete due to garbage collection.
Return object
result array[ ScriptCoverage ]Coverage data for the current isolate.
Profiler.setSamplingInterval #
Changes CPU profiler sampling interval. Must be called before CPU profiles recording started.
Parameters
interval integerNew sampling interval in microseconds.
Profiler.startPreciseCoverage #
Enable precise code coverage. Coverage data for JavaScript executed before enabling precise code coverage may be incomplete. Enabling prevents running optimized code and resets execution counters.
Parameters
callCountOptional
booleanCollect accurate call counts beyond simple 'covered' or 'not covered'.
detailedOptional
booleanCollect block-based coverage.
allowTriggeredUpdatesOptional
booleanAllow the backend to send updates on its own initiative
Return object
timestamp numberMonotonically increasing time (in seconds) when the coverage update was taken in the backend.
Profiler.stopPreciseCoverage #
Disable precise code coverage. Disabling releases unnecessary execution count records and allows executing optimized code.
Profiler.takePreciseCoverage #
Collect coverage data for the current isolate, and resets execution counters. Precise code coverage needs to have started.
Return object
result array[ ScriptCoverage ]Coverage data for the current isolate.
timestamp numberMonotonically increasing time (in seconds) when the coverage update was taken in the backend.
Events
Profiler.consoleProfileFinished #
Parameters
id stringlocation Location of console.profileEnd().
profile titleOptional
stringProfile title passed as an argument to console.profile().
Profiler.consoleProfileStarted #
Sent when new profile recording is started using console.profile() call.
Parameters
id stringlocation Location of console.profile().
titleOptional
stringProfile title passed as an argument to console.profile().
Types
Profiler.CoverageRange #
Coverage data for a source range.
Type: object
Properties
startOffset integerJavaScript script source offset for the range start.
endOffset integerJavaScript script source offset for the range end.
count integerCollected execution count of the source range.
Profiler.FunctionCoverage #
Coverage data for a JavaScript function.
Type: object
Properties
functionName stringJavaScript function name.
ranges array[ CoverageRange ]Source ranges inside the function with coverage data.
isBlockCoverage booleanWhether coverage data for this function has block granularity.
Profiler.PositionTickInfo #
Specifies a number of samples attributed to a certain source position.
Type: object
Properties
line integerSource line number (1-based).
ticks integerNumber of samples attributed to the source line.
Profiler.Profile #
Profile.
Type: object
Properties
nodes array[ ProfileNode ]The list of profile nodes. First item is the root node.
startTime numberProfiling start timestamp in microseconds.
endTime numberProfiling end timestamp in microseconds.
samplesOptional
array[ integer ]Ids of samples top nodes.
timeDeltasOptional
array[ integer ]Time intervals between adjacent samples in microseconds. The first delta is relative to the profile startTime.
Profiler.ProfileNode #
Profile node. Holds callsite information, execution statistics and child nodes.
Type: object
Properties
id integerUnique id of the node.
callFrame Function location.
hitCountOptional
integerNumber of samples where this node was on top of the call stack.
childrenOptional
array[ integer ]Child node ids.
deoptReasonOptional
stringThe reason of being not optimized. The function may be deoptimized or marked as don't optimize.
positionTicksOptional
array[ PositionTickInfo ]An array of source position ticks.
Profiler.ScriptCoverage #
Coverage data for a JavaScript script.
Type: object
Properties
scriptId JavaScript script id.
url stringJavaScript script name or url.
functions array[ FunctionCoverage ]Functions contained in the script that has coverage data.