o(1) to the rescue

o(1) to the rescue

[Ed Tomlinson]

Try this with and without the o(1) scheduler (J0).

Create a dir full of 1 meg or so jpegs.  Fire up kde.  Try using the Tools/Create image gallery.  
With the standard scheduler linux is unusable - it stalls for most of the processing time for 
each image.   With o(1) its just a little jerky - still usable though (a gallery is building as I 
type this).  

Xmms playing to a arts server running with real time priority experienced no dropouts during 
the process.

This is on 2.4.17 no preempt or low latency patches applied.

Real improvement - nice work,

Ed Tomlinson

Re: o(1) to the rescue

[Nero]

Ed Tomlinson wrote:

>Try this with and without the o(1) scheduler (J0).
>
>Create a dir full of 1 meg or so jpegs.  Fire up kde.  Try using the Tools/Create image gallery.  
>With the standard scheduler linux is unusable - it stalls for most of the processing time for 
>each image.   With o(1) its just a little jerky - still usable though (a gallery is building as I 
>type this).  
>
>Xmms playing to a arts server running with real time priority experienced no dropouts during 
>the process.
>
>This is on 2.4.17 no preempt or low latency patches applied.
>
>Real improvement - nice work,
>
>Ed Tomlinson
>-
>To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>the body of a message to majordomo@vger.kernel.org
>More majordomo info at  http://vger.kernel.org/majordomo-info.html
>Please read the FAQ at  http://www.tux.org/lkml/
>

Re: o(1) to the rescue

[Helge Hafting]

Ed Tomlinson wrote:
> 
> Try this with and without the o(1) scheduler (J0).
> 
> Create a dir full of 1 meg or so jpegs.  Fire up kde.  Try using the
> Tools/Create image gallery.
> With the standard scheduler linux is unusable - it stalls for most of the
> processing time for
> each image.   With o(1) its just a little jerky - still usable though (a
> gallery is building as I
> type this).

I guess this thing starts a thread per image?  That would
give a lot of _running_ processes, which is exactly what
the O(1) scheduler improves.

Helge Hafting

Re: o(1) to the rescue

[Ed Tomlinson]

On January 18, 2002 05:21 am, Helge Hafting wrote:
> Ed Tomlinson wrote:
> > Try this with and without the o(1) scheduler (J0).
> >
> > Create a dir full of 1 meg or so jpegs.  Fire up kde.  Try using the
> > Tools/Create image gallery.
> > With the standard scheduler linux is unusable - it stalls for most of the
> > processing time for
> > each image.   With o(1) its just a little jerky - still usable though (a
> > gallery is building as I
> > type this).
>
> I guess this thing starts a thread per image?  That would
> give a lot of _running_ processes, which is exactly what
> the O(1) scheduler improves.

No.  Just one thread running.  I think its the fact that o(1) detects when
a task is no longer interactive.   KDE is normally very interactive, when
building a gallery parts of it are not.  o(1) detect this and adjusts itself.

This is on a UP K6-III 400 with 512M memory.

Ed Tomlinson