Real-Time Video Recording (ionice equivalent)

Debacker debackerl at
Wed Jul 28 05:23:36 UTC 2010

On Tue, Jul 27, 2010 at 10:52 PM, Adam Vande More <amvandemore at>wrote:

> On Tue, Jul 27, 2010 at 2:29 PM, Debacker <debackerl at> wrote:
>> Of course, just like you could put real-time processes in one CPU, and
>> normal processes on another to avoid implement complex algorithms.
>> While your solution is pragmatic, I would like to know if there are
>> "clean"
>> ways to do it. If not, this would be a documented use case to why would
>> anyone actually need an I/O scheduler.
> First, top-posting on this list is considered rude.  Please don't do that.

Sorry, I didn't want to hurt anyone, I just didn't know the traditions of
this mailing-list, I'll be careful from now on.

If you're running 8.1, try "man gsched", it's new and haven't tried it.

Excellent! I can use 8.1, it's for a new setup.

> Other than that, the traditional way would be to give higher priority to
> the process that needs it.  It's the poor man's io scheduler, but it
> generally does work well.
> If you have lots of concurrent io and are running a UFS file-system,
> consider running gjournal as it scales those requests better.
> Also if you're hardware supports it, NCQ is available via the ahci and a
> few other modules.  It will make your requests more efficient.

Thank you for your tips. I'm happy that I will be able to use FreeBSD for
this job.

Laurent Debacker

More information about the freebsd-questions mailing list