module profiler

Memory profiler module

Instructions:

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var profiler = require('profiler');

static function

getHeapCodeStatistics

Get = statistics about the code in the v8 heap and its metadata

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static Object profiler.getHeapCodeStatistics();

Return results:

• Object, returns statistical information of metadata

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getHeapSpaceStatistics

Get detailed usage of v8 heap memory

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static Array profiler.getHeapSpaceStatistics();

Return results:

• Array, returns the detailed usage of heap memory

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getHeapStatistics

Get v8 heap memory usage statistics

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static Object profiler.getHeapStatistics();

Return results:

• Object, returns statistics on heap memory usage

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saveSnapshot

Save a heap snapshot under the specified name

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static profiler.saveSnapshot(String fname);

Call parameters:

• fname: String, heap snapshot name

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loadSnapshot

Read a heap snapshot based on the specified name

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static HeapSnapshot profiler.loadSnapshot(String fname);

Call parameters:

• fname: String, heap snapshot name

Return results:

• HeapSnapshot, returns the read heap snapshot

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takeSnapshot

Obtain the heap snapshot of the current time node. The heap snapshot records the status of the JS heap at the current moment.

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static HeapSnapshot profiler.takeSnapshot();

Return results:

• HeapSnapshot, returns the obtained heap information snapshot

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diff

Execute the given function and compare the changes in the v8 heap before and after execution

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static Object profiler.diff(Function test);

Call parameters:

• test: Function, given the function to be tested

Return results:

• Object, returns the comparison result

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start

Start a running status sampling log

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static Timer profiler.start(String fname,
    Integer time = 60000,
    Integer interval = 100);

Call parameters:

• fname: String, given log storage file name
• time: Integer, specifies the sampling time, the default is 1 minute
• interval: Integer, specify the interval time, the default is 100 milliseconds

Return results:

• Timer, returns the sampling timer, you can stop sampling early through the clear method

constant

Node_Hidden

Hidden nodes that can be filtered out when displayed to the user

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const profiler.Node_Hidden = 0;

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Node_Array

array

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const profiler.Node_Array = 1;

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Node_String

string

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const profiler.Node_String = 2;

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Node_Object

JS objects (except strings and arrays)

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const profiler.Node_Object = 3;

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Node_Code

compiled code

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const profiler.Node_Code = 4;

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Node_Closure

function closure

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const profiler.Node_Closure = 5;

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Node_RegExp

regular expression

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const profiler.Node_RegExp = 6;

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Node_HeapNumber

Sorted numbers in a heap

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const profiler.Node_HeapNumber = 7;

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Node_Native

Native object (non-v8 heap)

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const profiler.Node_Native = 8;

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Node_Synthetic

Synthetic object

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const profiler.Node_Synthetic = 9;

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Node_ConsString

concatenated strings

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const profiler.Node_ConsString = 10;

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Node_SlicedString

split string

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const profiler.Node_SlicedString = 11;

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Node_Symbol

Symbols (ES6)

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const profiler.Node_Symbol = 12;

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Node_SimdValue

Sorted SIMD values ​​in the heap (ES7)

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const profiler.Node_SimdValue = 13;

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Edge_ContextVariable

variables in functions

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const profiler.Edge_ContextVariable = 0;

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Edge_Element

elements in array

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const profiler.Edge_Element = 1;

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Edge_Property

Properties of named objects

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const profiler.Edge_Property = 2;

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Edge_Internal

JS cannot enter the link

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const profiler.Edge_Internal = 3;

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Edge_Hidden

Point to the node whose space size needs to be calculated in advance

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const profiler.Edge_Hidden = 4;

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Edge_Shortcut

Points to a node whose space size cannot be calculated in advance

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const profiler.Edge_Shortcut = 5;

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Edge_Weak

a weak reference (ignored by GC)

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const profiler.Edge_Weak = 6;