Re: [RFCv2 00/48] perf tools: Add threads to record command

[Jiri Olsa]

On Fri, Sep 14, 2018 at 10:26:53AM +0200, Jiri Olsa wrote:

SNIP

> > > The threaded monitoring currently can't monitor backward maps
> > > and there are probably more limitations which I haven't spotted
> > > yet.
> > > 
> > > So far I tested on laptop:
> > >   http://people.redhat.com/~jolsa/record_threads/test-4CPU.txt
> > > 
> > > and a one bigger server:
> > >   http://people.redhat.com/~jolsa/record_threads/test-208CPU.txt
> > > 
> > > I can see decrease in recorded LOST events, but both the benchmark
> > > and the monitoring must be carefully configured wrt:
> > >   - number of events (frequency)
> > >   - size of the memory maps
> > >   - size of events (callchains)
> > >   - final perf.data size
> > > 
> > > It's also available in:
> > >   git://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
> > >   perf/record_threads
> > > 
> > > thoughts? ;-) thanks
> > > jirka
> > 
> > It is preferable to split into smaller pieces that bring 
> > some improvement proved by metrics numbers and ready for 
> > merging and upstream. Do we have more metrics than the 
> > data loss from trace AIO patches?
> 
> well the primary focus is to get more events in,
> so the LOST metric is the main one

actualy I was hoping, could you please run it through the same
tests as you do for AIO code on some huge server? 

thanks,
jirka