Message-ID: <421E3916.6070005@nortel.com>
Date: Thu, 24 Feb 2005 14:29:10 -0600
From: Chris Friesen <cfriesen@nortel.com>
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To: "Chad N. Tindel" <chad@tindel.net>
CC: Paulo Marques <pmarques@grupopie.com>, Mike Galbraith <EFAULT@gmx.de>,
       akpm@osdl.org, linux-kernel@vger.kernel.org
Subject: Re: Xterm Hangs - Possible scheduler defect?
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Chad N. Tindel wrote:

> OK.  Would you say it would be a reasonable default to have SCHED_FIFO userspace
> threads running at a lower priority than essential kernel threads (say, the
> load balancer and the events thread), and give root the ability to explicitly 
> have userspace threads preempt the kernel?

The current scheduler has a 1-100 priority range for soft realtime 
tasks.  To insert a task into a realtime class, you need to have root 
privileges.

As long as you make sure that kernel threads get set to higher 
priorities than your user threads, then you get the above behaviour. 
Ultimately, however, the administrator is responsable for ensuring that 
everything is running with sane priority levels.

Chris
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