Re: [PATCH] [request for inclusion] Realtime LSM

Arjan van de Ven
2005-01-07T16:04:57Z

On Fri, Jan 07, 2005 at 10:41:40AM -0500, Paul Davis wrote:
>
> fine, so the mlock situation may have improved enough post-2.6.9 that
> it can be considered fixed. that leaves the scheduler issue. but
> apparently, a uid/gid solution is OK for mlock, and not for the
> scheduler. am i missing something?

I think you skipped a step. You don't have a scheduler requirement, you have
a latency requirement. You currently *solve* that latency requirement via a
scheduler "hack", yet is quite clear that the "hard" realtime solution is
most likely not the right approach. Note that I'm not saying that you
shouldn't get the latency that that currently provides, but the downsides
(can hang the machine) are bad; a solution that solves that would be far
preferable
something like a soft realtime flag that acts as if it's the hard realtime
one unless the app shows "misbehavior" (eg eats its timeslice for X times in
a row) might for example be such a solution. And with the anti abuse
protection it can run with far lighter privilegs.