[lttng-dev] [diamon-discuss] My experience on perf, CTF and TraceCompass, and some suggection.

[Alexandre Montplaisir]

On 01/23/2015 04:35 AM, Wang Nan wrote:
> [...] I prefer to use:
>
>   # perf record -a -e sched:* -e syscalls:* sleep 1
>
> However there are some bugs and I have to make some patches. They are
> posted and being disscussed currently, those bugs are still exist
> upstream.

Hmm, I can confirm this problem, when trying to convert a trace taken 
with these events enabled, I get the following error:

Failed to add field 'nr
Failed to add event 'syscalls:sys_enter_io_submit'.

Good to know it's being looked at!


But when you say:

> TraceCompass doesn't recognize syscall:* tracepoints as CPU status
> changing point. I have to also catch raw_syscall:*, and which doubles
> the number of samples.

I assume this was that with your patches applied, so that you could take 
a trace of the syscall:* tracepoints?

Do you have a link to those patches somewhere? Or just let us know when 
it gets integrated upstream. I was trying to update the analysis in 
Trace Compass to handle syscall:* too, but we can't really do it without 
knowing how it will look like in CTF format ;)


Cheers,
Alexandre