[PATCH] QA: Add log for wayland performance analysis

[Pekka Paalanen]

On Fri, 6 Feb 2015 14:21:13 +0000
Daniel Stone <daniel at fooishbar.org> wrote:

> Hi Quanxian,
> 
> On 6 February 2015 at 09:52, Quanxian Wang <quanxian.wang at intel.com>
> wrote:
> > This patch is to provide the mechanism to track weston rendering
> > performance.
> 
> Have you seen the JSON timeline debugging already available in Weston?
> Is this something you can use in your tool?

For the record, you start/stop it with the debug key binding 't' (hit
mod+shift+space, then hit 't'). It writes a file per each start to
weston's cwd. These files can be visualised by
https://github.com/ppaalanen/wesgr

It was introduced in
http://cgit.freedesktop.org/wayland/weston/commit/?id=b502654b9fd9263964ccc4bdcbd8d633233b4f87

It is extendable to new kinds of tracepoints and objects to be dumped,
but in the long run I'd like to see something "standard" that is not
written just for Weston. For instace, something that ties in with
'perf' with userspace probe points defined in the source or added
dynamically at profiling time. Also something that produces data in a
format accepted by interactive graphical analysis tools, and would also
support live monitoring. But that's a very long time goal.

Why 'perf' in particular? For taking advantage of the profiling and
tracing infrastructure already in place in the kernel, which can
provide information about the GPU drivers' workings.


Thanks,
pq