[Piglit] [PATCH 0/3] apitrace test runner for piglit

[Jose Fonseca]

On 14/09/16 11:03, Eric Anholt wrote:
> I've applied Dylan's comments to the RFC series, and I've pushed a
> starting trace-db with reference images for my i965 and vc4:
>
> https://github.com/anholt/trace-db

Eric,

This is great initiative IMO.


One suggestion: you can get much smaller traces by repacking traces into 
the Brotli format.

For example:

   $ wget 
https://github.com/anholt/trace-db/raw/master/traces/humus/HDR.trace
   $ apitrace repack --brotli HDR.trace HDR.brotli.trace
   $ du -sh HDR*.trace
   4.5M	HDR.brotli.trace
   7.2M	HDR.trace


I introduced Brotli format precisely because some legacy OpenGL apps 
that don't use VBOs yield a mind boggling traces.  But with effective 
compression it's managable again.  For some of these we see traces 10x 
smaller going from snappy to brotli.

The decompression speed is a bit slower in terms of CPU, but when 
factored disk access time, it's a net win too.


The only thing to keep in mind is that qapitrace will not work with 
brotli files because they are not seekable.  But it's just a matter of 
repacking again to snappy (the repack operation is lossless.)


Jose