In general, does redirecting outputs to /dev/null enhance performance?

Question

Suppose I have a program that prints a large number of messages to stdout, which takes much time. I wonder whether by redirecting the stdout to /dev/null (so that I see no messages in the screen) we can make the program terminate faster?

[Edit] I tries with small examples. Redirecting stdout to /dev/null does make program terminate earlier.

score 3 · Accepted Answer · answered Feb 06 '16 at 19:34

3

Yes. Outputting to the screen requires a lot of painting. Outputting to a file is much faster, because it's running at disc speed. Outputting to /dev/null is faster yet, because the output goes nowhere.

answered Feb 06 '16 at 19:34

Mike Dunlavey

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When I stored it in avariable and redirect to it I found it slower than expected! `[[ $hide_output ]] && hide=/dev/null` and `./command >>$hide` – Mamdouh Saeed May 17 '23 at 05:16
@MamdouhSaeed: Whenever I have a question about speed, I do [*this*](https://stackoverflow.com/a/378024/23771). – Mike Dunlavey May 18 '23 at 12:06

In general, does redirecting outputs to /dev/null enhance performance?

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