Re: Burning multiple DVDs at one time

From: Stefan Richter
Date: Sun Mar 18 2012 - 10:02:07 EST


On Mar 18 Wakko Warner wrote:
> Stefan Richter wrote:
> > On Mar 17 Wakko Warner wrote:
> > > Thanks. I looked at the patch. I would just like to confirm that I can
> > > patch my 3.0.0 vanilla kernel, compile the sr module, unload the current and
> > > load the patched one without the need to reboot.
> >
> > Yes, this should be possible.
> >
> > Oh, I only noticed just know that you also wrote:
> >
> > > > > The kernel is a vanilla kernel v3.0.0. (This also happened with 2.6.35)
> >
> > In 2.6.35, the Big Kernel Lock was still in place there. That lock
> > behaved differently from a plain mutex --- notably it was released when a
> > thread went to sleep --- so maybe there is more to your problem than just
> > sr_mutex blocking unrelated sr accesses.
>
> There is a good possibility that I was mistaken on the 2.6.35.
>
> I manually applied your patch to 3.0.0, compiled, removed sr-mod module and
> inserted the newly compiled one.
>
> With the vanilla one, I would see the buf % in wodim drop while the fifo was
> full. With the patch (removing the mutex), buf stayed above 98% and the
> burn speed was 16x at the end (10x avg).
>
> Seems to have fixed my problem.

Very nice; so there is an almost easy fix. Now I or somebody else need to
work out the required cdrom_device_info protection on which Arnd and James
commented.
--
Stefan Richter
-=====-===-- --== =--=-
http://arcgraph.de/sr/
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