Subject: Re: PROBLEM: Only 2 of 4 cores used on IBM Cell blades and no threads shown in spufs

From: Dennis Schridde <[email-masked]>
Date: Tue, 23 Apr 2013 13:51:55 +0200

Hello Michael!

Am Tue, 23 Apr 2013 19:12:47 +1000
schrieb Michael Ellerman <[email-masked]>:
> On Mon, Apr 22, 2013 at 06:44:13PM +0200, Dennis Schridde wrote:
> For me it is fixed by applying the following patch, it should be in
> v3.10:

I am currently compiling the patched kernel. Will report back with the
results later.

> Does your cellminer actually work? ie. does it run OK?
> 
> I am using a fractal benchmark I had lying around, and it appears to
> work, and runs fast enough that it must be running on the SPUs (I
> think).
> 
> So it sounds like we have some weirdness with stuff not appearing in
> /spu, but spu programs are still able to run. Which is odd to say the
> least.

Yes, that seems to be exactly what I see here. The SPE code seems to be
actually running (cellminer reports SPU threads being created and it
runs at 42 Megahash/s - which is coming closer and closer to the
expected ~60Mh/s, given that I started with about 6Mh/s), just /spu is
empty.