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Comment by brcmthrowaway | Hacker News Reader

Is Linux/Windows/Mac tickless?

From https://en.wikipedia.org/wiki/Tickless_kernel

"The Linux kernel on s390 from 2.6.6[2] and on i386 from release 2.6.21 can be configured to turn the timer tick off... The XNU kernel from Mac OS X 10.4 on, and the NT kernel from Windows 8 on, are also tickless. The Solaris 8 kernel introduced the cyclic subsystem which allows arbitrary resolution timers and tickless operation. FreeBSD 9 introduced a "dynamic tick mode" (aka tickless).

What about beOS?

Unsure if this is clear so I'll say it: Those are not real time OSs

Pretty sure that most people here know that, so it remains a less obvious yet interesting question (while tangential to the posted article): Are Linux/Windows/Mac tickless?

I know Linux is, the rest probably are too. I remember when tickless support was merged:

https://lwn.net/Articles/549580/

https://lwn.net/Articles/659490/

My Linux sure is. It's a good idea for battery-powered devices.

    $ zgrep ^CONFIG_NO_HZ /proc/config.gz
    CONFIG_NO_HZ_COMMON=y
    CONFIG_NO_HZ_FULL=y
    CONFIG_NO_HZ=y

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