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Subject: Re: [tip:perfcounters/core] perf stat: handle Ctrl-C
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Paul Mackerras <paulus@samba.org>
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Date: Thu, 28 May 2009 14:19:03 +0200
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On Thu, 2009-05-28 at 21:09 +1000, Paul Mackerras wrote:
> tip-bot for Ingo Molnar writes:
> 
> > perf stat: handle Ctrl-C
> > 
> > Before this change, if a long-running perf stat workload was Ctrl-C-ed,
> > the utility exited without displaying statistics.
> > 
> > After the change, the Ctrl-C gets propagated into the workload (and
> > causes its early exit there), but perf stat itself will still continue
> > to run and will display counter results.
> > 
> > This is useful to run open-ended workloads, let them run for
> > a while, then Ctrl-C them to get the stats.
> 
> Unfortunately it means that if you do e.g.
> 
> $ while true; do perf stat something; done
> 
> it's impossible to kill the loop with ctrl-C.  To fix this we need to
> make perf stat kill itself with the signal after printing the results,
> so bash sees the died-due-to-signal exit status and stops the loop.

Yep, just ran into the same..

^Z kill $! worked though, but that's not ideal.