From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: toplev would hang forever when analyzing a program with PID
Date: Mon, 27 Mar 2017 13:35:38 -0700
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        (Yijie Shen's message of "Sun, 26 Mar 2017 22:07:44 +0800")
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To: Yijie Shen <henry.yijieshen@gmail.com>
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Yijie Shen <henry.yijieshen@gmail.com> writes:
>
>
> this would hang forever even if the process with such pid end, this
> happens whatever the pid is pointing at is, a Java process or a Linux
> tool such as top.
>
>
> Am I doing something wrong? What does the right command look like to
> analyze a program using PID?

You're using SMT, so toplev has to enable global monitoring (-a),
but that does not interact well with --pid in perf.

That's more a perf bug .

It would work in single thread mode or without SMT, or using intervals.

toplev should probably print a warning in this case.

-Andi

>