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---
title: "Linux by default doesn't allow any increase in scheduling priority. Users need t"
author: "NOTimothyLottes"
handle: "@NOTimothyLottes"
post_url: "https://x.com/NOTimothyLottes/status/2072135292115427728"
post_id: "2072135292115427728"
timestamp: "2026-07-01 01:48:46"
post_count: 6
reply_count: 1
repost_count: 0
like_count: 3
view_count: 381
---

# @NOTimothyLottes — Linux by default doesn't allow any increase in scheduling priority. Users need t

## Post 1 (2026-07-01 01:45:40)

Working on the portable thread scheduling priority interface. Windows is a bit nicer by default, one can increase the scheduling priority without admin and there is a AvSetMmThreadCharacteristics() / AvSetMmThreadPriority() hack for "Pro Audio" scheduling needs.

## Post 2 (2026-07-01 01:48:46) — reply to Post 1

Linux by default doesn't allow any increase in scheduling priority. Users need to manually setup special user|group with elevated rights. Also system calls that try elevated scheduling don't clamp, instead they fail -EPREM if out of bounds. So all around a pain in the ass.

![Media 1](./media/2072135292115427728_1.png)

## Post 3 (2026-07-01 01:51:56) — reply to Post 2

I'm a little lazy right now and don't feel like trying SteamOS big picture mode to see what the default ulimits are. Curious what they allow.

## Post 4 (2026-07-01 02:36:48) — reply to Post 3

Linux priority workarounds
(a.) Use getrlimit() to get {soft,hard} limits
(b.) Use setrlimit() to set 'soft=hard' limit
(c.) Then set priority or nice based on new soft limit

![Media 1](./media/2072147378480566273_1.png)
![Media 2](./media/2072147378480566273_2.png)

## Post 5 (2026-07-01 02:38:20) — reply to Post 4

I don't do one-time global priority maximums, just in case someone sudo's higher priority hard limit dynamically it should pickup the new limit.

## Post 6 (2026-07-01 02:46:03) — reply to Post 5

Also while on setrlimit, I also bump up the RLIMIT_MEMLOCK to it's maximum just in case before the mlockall().

![Media 1](./media/2072149707107787035_1.png)