Re: [RFC PATCH v2 0/4] CPUs capacity information for heterogeneous systems

From: Steve Muckle
Date: Mon Jan 18 2016 - 14:25:48 EST


On 01/18/2016 07:13 AM, Juri Lelli wrote:
>> DT solves these issues and would be the perfect place for this - we are
>> > defining the compute capacity of a CPU which is a property of the
>> > hardware. However there are a couple things forcing us to compromise.
>> > One is that the amount and detail of information required to adequately
>> > capture the computational abilities of a CPU across all possible
>> > workloads seem onerous to collect and enumerate. The second is that even
>> > if we were willing to undertake that, CPU vendors probably won't be
>> > forthcoming with that information.
>> >
>
> You mean because they won't publish performance data of their hw?

More specific things like IPC and other architectural details that could
comprise a precise physical definition of a CPU that would meet the
ideal goals of a device tree definition.

> But we already use per platform normalized values (as you are proposing
> below). So that a platform to platform comparison doesn't make sense.

Yeah I'm just advocating for that strategy here.

cheers,
Steve