[gst-devel] strange CPU loading for audiotestsrc and filesrc

[Michael Smith]

On Wed, Oct 7, 2009 at 10:49 PM, Viraj Karandikar <virajk at gmail.com> wrote:
> Hi,
>
> I am seeing some strange behaviour while doing CPU load measurement when
> running gstreamer.
> I am relying on uptime and idle time give by "cat /proc/uptime" to calculate
> CPU load.
> We have implemented custom audio source (dalsrc) and sink (dalsink) plugins
> for our board (ARM9E on TI DM6446).
> I am using gstreamer-0.10.24.
>
> I have following two cases:
>
> Case 1:
> gst-launch audiotestsrc wave=silence is_live=true blocksize=160 !
> audio/x-raw-int,rate=8000,depth=16,channels=2,width=16,signed=\(boolean\)TRUE,endianness=\(int\)1234
> ! dalsink
> Average CPU load over 5 minutes : 18%

As well as your cpu usage measurement technique being pretty
inaccurate, it's not surprising that audiotestsrc is slow - it's a
test element, and has has absolutely no optimisation done, or even any
attempt to make it vaguely ok. It's probably just doing something
stupid for the silence case.

Additionally, the first case is a live source - your second isn't.
Those aren't very directly comparable. There might be something that's
slower because of that.

Mike