Re: [PATCH v8 0/3]: perf: reduce data loss when profiling highly parallel CPU bound workloads
From: Jiri Olsa
Date: Mon Sep 10 2018 - 06:08:47 EST
On Mon, Sep 10, 2018 at 12:03:03PM +0200, Ingo Molnar wrote:
> * Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
> > > Per-CPU threading the record session would have so many other advantages as well (scalability,
> > > etc.).
> > >
> > > Jiri did per-CPU recording patches a couple of months ago, not sure how usable they are at the
> > > moment?
> > it's still usable, I can rebase it and post a branch pointer,
> > the problem is I haven't been able to find a case with a real
> > performance benefit yet.. ;-)
> > perhaps because I haven't tried on server with really big cpu
> > numbers
> Maybe Alexey could pick up from there? Your concept looked fairly mature to me
> and I tried it on a big-CPU box back then and there were real improvements.
too bad u did not share your results, it could have been already in ;-)
let me rebase/repost once more and let's see
I think we could benefit from both multiple threads event reading
and AIO writing for perf.data.. it could be merged together