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Channel#writeAndFlush method costly

See original GitHub issue

Expected behavior

Since Netty is asynchronous and all I/O events are handled by EventLoop, there should be the minimal cost of calling Channel#writeAndFlush.

Actual behavior

However, for 1.2M writes, Channel#writeAndFlush is taking 26,925 ms.

Steps to reproduce

Just do lots of write and flush.

Minimal yet complete reproducer code (or URL to code)

N/A

Netty version

4.1.54.Final

JVM version (e.g. `java -version`)

Java 11

OS version (e.g. `uname -a`)

Linux DESKTOP-ANM4Q9I 4.19.128-microsoft-standard Windows 10 Pro x64

Attaching a screenshot of JProfiler. Screenshot (60)

Issue Analytics

State:
Created 3 years ago
Comments:24 (24 by maintainers)

Top GitHub Comments

1reaction

normanmaurercommented, Dec 4, 2020

@hyperxpro if you have any perf numbers to share (before and later) in terms of thoughtput please let us know

1reaction

hyperxprocommented, Dec 4, 2020

IO_URING on Fire. Free 5x performance improvement over Epoll. 🔥🔥🔥🔥

Screenshot (62)

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