Hi, We are looking at accelerating video operations using vaapi/intel-driver. When using Ivy bridge we believe that the GPU is (almost always) not turboing even when 100% busy doing vaapi video things (e.g. image scaling on EUs or bitstream decode). To determined this we use cat /sys/kernel/debug/dri/0/i915_cur_delayinfo and GPU top (todays IVB fixed vesion). We have tried a variety of IVB parts from 3610QE up to 3770 - all do the same. We've mainly been using kernel 3.2.0-24-generic and libdrm 2.4.32. The same machines turbo correctly when doing equivent things in windows using intel media SDK. I get the impression from mailing lists that turbo is known to have driver/sw issues. Can anyone suggest if there is a later kernel/drm version that might improve things? If so where do we find it? This is for evaluation so we're happy to try unstable latest software. Thanks! Bloggsian
