[Mesa-dev] [PATCH 5/6] mesa: don't rebind constant buffers after every state change if GS is active

[Emil Velikov]

Strange I was under the impression that there are apps that make use
of GS, albeit not too many.

On the perf side - I was thinking about the hardware (i.e. regardless
if the driver does extra state-tracking or not) - would there be the
optimisation mentioned, would there be a "stall" in the pipeline, due
to the "new" values being flushed/fetched/etc. Now that I think about
it, only a few of the HW guys may know the answer on this one, so
don't bother with this.

Thanks
Emil

On 16 June 2015 at 20:56, Marek Olšák <maraeo at gmail.com> wrote:
> There are probably 0 apps using GS, so the answer is 0.
>
> The hardware doesn't ignore anything. It only does what it's told to do.
>
> The radeonsi driver doesn't check if the state change is redundant or not.
>
> Marek
>
> On Tue, Jun 16, 2015 at 10:13 PM, Emil Velikov <emil.l.velikov at gmail.com> wrote:
>> Hi Marek,
>>
>> Out of curiosity:
>> Any rough idea of how much of a perf. improvement this might bring ?
>> Would the hardware ignore the newly (re)bound const. bufs, when the
>> values are unchanged ?
>>
>> Thanks
>> Emil
>>