[mythtv] Watch Recordings is slow with SVN on my Epia

[Daniel Kristjansson]

On Tue, 2006-08-29 at 08:36 +0200, Daan de Beer wrote:
> Hello All,
> 
> As advised, I profiled my system using OProfile, but it seems I can not use 
> any profiling events, since my CPU is not supported or something. I enabled 
> all APIC options, disabled SMP and compiled the oprofile kernel support as 
> module. Profiling does work, so I do not know wether or not it is a problem 
> that only timing is supported.
This just means that you need much longer runs to get meaningful reports.


> Results from profiling:
> 
> pvr1 linux # opreport
> CPU: CPU with timer interrupt, speed 0 MHz (estimated)
> Profiling through timer interrupt
>           TIMER:0|
>   samples|      %|
> ------------------
>      2159 49.4050 vmlinux
>      1775 40.6178 libfb.so

> 
> pvr1 linux # opreport -xf --merge tgid
> CPU: CPU with timer interrupt, speed 0 MHz (estimated)
> Profiling through timer interrupt
>           TIMER:0|
>   samples|      %|
> ------------------
>      2159 49.4050 /usr/src/linux-2.6.17-suspend2-r4/vmlinux
>      1775 40.6178 /usr/lib/xorg/modules/libfb.so

> 
> This means little to me, but what I understand from it, a lot of CPU is taken 
> by libfb.so. Can I do something more to debug this?


You should compile libfb with debugging symbols and you also
need to load the symbols for the Linux kernel so we see where
it is spending it's time. 

strace on mythfrontend will tell you what calls it is
making. But without knowing what is taking so much
time in the framebuffer library and the Linux kernel
that info isn't useful yet.

-- Daniel