slow-code-detector
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    1.0.3 • Public • Published

    Slow-Code-Detector

    Tool to show slow calls in your code runned by v8.

    Install

    npm i -g slow-code-detector

    How to use

    scd your-index-js-file.js – it creates bunch of files in current directory code.asm hydrogen.cfg out.txt code.html

    code.html – is what you need, open it in the browser.

    Also you can generate markdown file code.md, just run with --md option: scd --md index.js

    Generated code.html groupped by files and functions.

    code.html

    Every runtime call highlighted by gray. Call cost ~4ns.

    Pink highlight is LoadGeneric or StoreGeneric. Generic read or write cost ~9ns.

    If function in code is inlined it highlighted by blue, you can show its code by click.

    If function is not inlined you can show non inline reason by a hint on call function name.

    If function deoptimized, it colored by red.

    Every function reoptimization marked by ~recompile~ – max 10 times, else deopt: Optimize too many times

    How it works

    The scd execute node with some v8 trace options and parse given logs to find slow path calls.

    node --trace-inlining --trace-hydrogen --trace-phase=Z --trace-deopt

    IRHydra

    You can use hydrogen.cfg and code.asm with IRHydra to investigate internal representation of your code

    Keywords

    none

    Install

    npm i slow-code-detector

    DownloadsWeekly Downloads

    7

    Version

    1.0.3

    License

    ISC

    Unpacked Size

    223 kB

    Total Files

    26

    Last publish

    Collaborators

    • cevek