[Mesa-dev] [PATCH 2/2] i965: Throttle to the previous frame

[Chad Versace]

On 03/06/2015 01:58 PM, Chris Wilson wrote:
> In order to facilitate the concurrency offered by triple buffering and to
> offset the latency induced by swapping via an external process, which
> may incur extra rendering itself, only throttle to the previous frame
> and not the last. The second issue that mostly affects swap benchmarks,
> but also can incur jitter in the throttling, is that the throttle bo is
> closer to the next SwapBuffers rather than immediately after the previous
> SwapBuffers. Throttling to the previous frame doubles the maximum possible
> latency at the benefit of improving throughput and reducing jitter.
> 
> v2: Rename "first_post_swapbuffer" batches array to a plain
> throttle_batch[] as the pluralisation was contorting the name and not
> making it clear as to whether it was the first batch or first_post_swap
> batch. Not least of which was that not all throttle points are SwapBuffers.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Cc: Kenneth Graunke <kenneth at whitecape.org>
> Cc: Ben Widawsky <ben at bwidawsk.net>
> Cc: Kristian Høgsberg <krh at bitplanet.net>
> Cc: Chad Versace <chad.versace at linux.intel.com>

Both patches
Reviewed-by: Chad Versace <chad.versace at intel.com>