Re: [PATCH v3 0/3] perf: add new option '--workload-attr' to set workload sched_policy/priority/mask

[Changbin Du]

On Mon, Jul 24, 2023 at 08:44:12AM +0300, Adrian Hunter wrote:
> On 24/07/23 07:02, Changbin Du wrote:
> > On Thu, Jul 20, 2023 at 01:00:58PM +0300, Adrian Hunter wrote:
> >> On 18/07/23 06:33, Changbin Du wrote:
> >>> This adds a new option '--workload-attr' to set the sched_policy/priority/mask
> >>> of the workload to reduce system noise.
> >>>
> >>> $ sudo perf stat --workload-attr fifo,40,0-3:7 -- ls
> >>
> >> Not really sold on the need for this, but maybe it could be
> >> simpler.
> >> What about just adding a hook for a command (e.g. script) to
> >> run before exec'ing the workload e.g.
> >>
> >> --configure-workload=blah.sh
> >>
> >> results in perf doing system("blah.sh 12345") where 12345
> >> is the workload PID.
> >>
> >> Then maybe you could do:
> >>
> >> --configure-workload="taskset -p 0x3"
> >>
> > Acctually, we already have such option for perf-stat.
> > 
> > 	--post <command>  command to run after to the measured command
> >         --pre <command>   command to run prior to the measured command
> > 
> > By involving a shell script we can do more complex setup. But sometimes I just
> > need to set sched attributes. For example, to investigate the impact of
> > various compiler optimizations. In this case, I don't want a script. This is the
> > original purpose I try to add this new option.
> 
> There is also command schedtool, but what exactly is the problem
> with a script?
> 
> > 
There is no problem with a script, just a shortcut for convenience. When I want
to share perf investigation with somebody, I just need to share a single commandline.
Anyway nothing bad, right? :)


-- 
Cheers,
Changbin Du