[Intel-gfx] [PATCH 2/2] drm/i915: Disable page-faults around the fast pwrite/pread paths

[Chris Wilson]

On Sat, 09 Jul 2011 15:07:28 -0700, Keith Packard <keithp at keithp.com> wrote:
Non-text part: multipart/signed
> On Sat, 09 Jul 2011 22:23:28 +0100, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> > I can stick some counters in there and find out what the impact actually
> > is.

On a SNB laptop, so surplus memory and surplus processing power, we don't
see that many faults at all whilst messing around with firefox, gitk and a
couple of timedemos (padman, openarena):

no-prefaulting:
  pread: shmem fast: 1273764/3395, slow: 0/0
  pwrite: sheme fast: 51163148/14554, slow: 23552/9
  pwrite: gtt fast: 32744702068/12658489, slow: 29376/10

all-prefaulted:
  pread: shmem fast: 6081544/5999, slow: 0/0
  pwrite: shmem fast: 56867580/15932, slow: 0/0
  pwrite: gtt fast: 32976168476/12753355, slow: 0/0

I'll look at a PNV netbook next.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre