Re: Plumbers: Tweaking scheduler policy micro-conf RFP

[Peter Zijlstra <a.p.zijlstra@chello.nl>]

On Tue, 2012-05-15 at 16:26 -0400, valdis.kletnieks@vt.edu wrote:
> On Tue, 15 May 2012 14:35:53 +0300, Pantelis Antoniou said:
> 
> > Thermal management: How to distribute load to the processors in such
> > a way that the temperature of the die doesn't increase too much that
> > we have to either go to a lower OPP or shut down the core all-together.
> > This is in direct conflict with throughput since we'd have better performance
> > if we could keep the same warmed-up cpu going.
> 
> It's not just "temperature of the die".  When you have multiple aisles of 42U
> racks full of servers, you often hit "must keep average total BTU load per
> server below X" constraints.  There's plenty of colo's that are only using 40%
> of their floor space due to cooling constraints (you may be able to get the
> power company to pull another megawatt of copper into the building, but then
> you need to find someplace to put another megawatt worth of cooling).

Yeah, I know.. sadly ACPI-4+ is a complete and utter trainwreck. But in
case someone wants to fix this proper I'm willing to talk.