Introduction

How to start

$ git clone https://github.com/zhangyuang/v8-profiler-rs.git$cd v8-profiler-rs/example$ yarn&& yarn start

Online Demo

Default example

constexpress=require('express');constapp=express();constfs=require('fs')// the memory leak codelettheThing=null;letreplaceThing=function(){letleak=theThing;letunused=function(){if(leak)console.log("hi")};theThing={bigNumber:1,bigArr:[],longStr:newArray(1000000),someMethod:function(){console.log('a');}};};letindex=0app.get('/leak',functionclosureLeak(req,res,next){replaceThing();index++if(index===1){conststream=require('v8').getHeapSnapshot()stream.pipe(fs.createWriteStream('small-closure.heapsnapshot'))}if(index===40){conststream=require('v8').getHeapSnapshot()stream.pipe(fs.createWriteStream('medium-closure.heapsnapshot'))}if(index===50){conststream=require('v8').getHeapSnapshot()stream.pipe(fs.createWriteStream('big-closure.heapsnapshot'))}res.send('Hello Node');});app.listen(3001);

Analyze Report

Single Report

Analyze Report with singleOnly show nodes with more than 20 occurrencesMemory retained by constructor typeclosure:156409.05 MBObject:156408.32 MBsystem / Context:154881.33 MBarray:4579.70 MBsynthetic:1533.60 MBArray:1526.16 MBWeakMap:1526.01 MB(compiled code):2.96 MBstring:2.10 MBThere are some nodes that are duplicated too many timessomeMethod @70761:202(memoryleak - demo / closure / index.js)HttpError @95957:44(node_modules / http - errors / index.js)parse @89241:33(node_modules / ms / index.js)ClientError @50469:31(node_modules / http - errors / index.js)indexOf @49211:27(node_modules / object - inspect / index.js)send @126827:23(node_modules / send / index.js)resolve @98543:23(node_modules / express / lib / view.js)

Compare Report

Analyze Report with compareOnly show nodes with more than 20 occurrencesAdditional nodes by constructor type(compiled code):242ArrayBuffer:127system / JSArrayBufferData:127Buffer:126Node / std::basic_string:78closure:69Array:46array:44system / Context:34Object:29Bigger nodes by constructor type(compiled code):48closure:25Bigger nodes by increased size@1: +83.54 MBObject @6613:+76.30 MBArray @154471:+76.30 MBArray @154499:+76.30 MBapp @6603:+76.30 MB(node_modules / .pnpm / express @4 .18 .2 / node_modules / express / lib / express.js)router @6533:+76.30 MB(node_modules / .pnpm / express @4 .18 .2 / node_modules / express / lib / router / index.js)closureLeak @6481:+76.30 MB(memoryleak - demo / closure / index.js)Route @6511:+76.30 MBLayer @6517:+76.30 MBLayer @6497:+76.30 MBServer @6609:+76.30 MBsystem / Context @6483:+76.30 MB

Implemented Features

Why Rust

Handling Parse Timeout Issues

Contact

There are two ways to sponsor me both Alipay and WeChat

Eth address: 0x87a2575a5d4dbD5f965e3e3a3d20641BC9a5d192

Open theonline demo and upload theheapsnapshot file. You can upload one or two files for comparison.

There will render heapsnapshot nodes in web page.

The node fields are as follows:

{"node_type":string;// node type"name":string;// node name"id":number;// node id"size":number;// node self size"edge_count":number;// node edge count"retained_size":number;// node retained size, the free size of the node after GC"pt":number;// the ratio of self size / retained size"edges":{"edge_type":string;// edge type"to_node":number;// the id of the node that the edge points to"name_or_index":string;// the name or index（for array） of the edge}[];"source":string;// the source file of the node"constructor":string;// the constructor of the node"percent":string;// the retained size ratio of the node}