Re: 50 Watt idle power regression bisected to Linux-3.10

[Thomas Gleixner]

On Tue, 10 Dec 2013, Mike Galbraith wrote:
> vogelweide:~/:[130]# turbostat -P -i 60
> pk cor CPU    %c0  GHz  TSC SMI    %c1    %c3    %c6 CTMP   %pc3   %pc6
>              0.02 2.12 2.26   0  43.40  56.57   0.00   53  33.81   0.00
>  0   0   0   0.23 2.10 2.26   5  65.47  34.30   0.00   52  10.69   0.00

...
 
> That, vs solid >99% pc3 for old 3.0 enterprise kernel.  What happened,
> dunno, kernel called itself master.  Whatever, I don't like test bogons,
> and this is one, so I thought I should let you know.  DL980 refuses to
> come close to the previous result.

Hmm, that's very similar to the issue Len is seing on his quad socket WM.

But I can't see it on my dual socket SNB, neither does PeterZ on his
dual socket WM machine. Heisenbugs ....

Can you offline all cpus except core 0, enable all trace events (nop
tracer), run "sleep 100" and stop and grab the trace? Please make sure
that your tracebuffer is big enough to cover the full thing.

Thanks,

	tglx
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/