Re: [PATCH] Enhance perf to collect KVM guest os statistics from host side

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
From: Andi Kleen
Date: Tuesday, March 23, 2010 - 7:20 am

Soeren Sandmann <sandmann@daimi.au.dk> writes:

That's something the JIT interface could answer.


I suspect for those you rather need event based tracers of some sort,
similar to kernel trace points. Otherwise you would need own
separate stacks and other complications.

systemtap has some effort to use the dtrace instrumentation
that crops up in more and more user programs for this.  It wouldn't
surprise me if that was already in python and other programs
you're interested in.

I presume right now it only works if you apply the utrace monstrosity
though, but perhaps the new uprobes patches floating around 
will come to rescue.

There also was some effort to have a pure user space
daemon based approach for LTT, but I believe that currently
needs own trace points.

Again I fully expect someone to reinvent the wheel here
and afterwards complain about "community inefficiences" :-)


That would require keeping those temporary ELF files for
potentially unlimited time around (profilers today look at the ELF
files at the final analysis phase, which might be weeks away)

Also that would be a lot of overhead for the JIT and most likely
be a larger scale rewrite for a given JIT code base.

-Andi
-- 
ak@linux.intel.com -- Speaking for myself only.
--
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]

Messages in current thread:
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Frank Ch. Eigler, (Thu Mar 18, 5:33 am)
Re: [PATCH] Enhance perf to collect KVM guest os statistic ..., Arnaldo Carvalho de Melo, (Thu Mar 18, 6:03 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Frank Ch. Eigler, (Thu Mar 18, 6:24 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Daniel P. Berrange, (Thu Mar 18, 6:44 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Frank Ch. Eigler, (Thu Mar 18, 7:39 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Anthony Liguori, (Thu Mar 18, 11:10 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Anthony Liguori, (Thu Mar 18, 11:20 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Frederic Weisbecker, (Thu Mar 18, 11:20 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Frank Ch. Eigler, (Thu Mar 18, 12:50 pm)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Olivier Galibert, (Fri Mar 19, 2:52 am)
Re: [LKML] Re: [RFC] Unify KVM kernel-space and user-space ..., Konrad Rzeszutek Wilk, (Fri Mar 19, 6:56 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Andrea Arcangeli, (Fri Mar 19, 7:53 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Andrea Arcangeli, (Sat Mar 20, 7:59 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Olivier Galibert, (Sun Mar 21, 1:08 pm)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Daniel P. Berrange, (Mon Mar 22, 5:37 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Daniel P. Berrange, (Mon Mar 22, 5:54 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Daniel P. Berrange, (Mon Mar 22, 6:05 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Richard W.M. Jones, (Mon Mar 22, 6:23 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Richard W.M. Jones, (Mon Mar 22, 7:01 am)
Re: [PATCH] Enhance perf to collect KVM guest os statistic ..., Arnaldo Carvalho de Melo, (Mon Mar 22, 9:44 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Frank Ch. Eigler, (Mon Mar 22, 10:17 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Anthony Liguori, (Mon Mar 22, 11:28 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Anthony Liguori, (Mon Mar 22, 11:30 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Anthony Liguori, (Mon Mar 22, 11:35 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Anthony Liguori, (Mon Mar 22, 11:41 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Anthony Liguori, (Mon Mar 22, 12:15 pm)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Anthony Liguori, (Mon Mar 22, 12:18 pm)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Andrea Arcangeli, (Mon Mar 22, 12:28 pm)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Anthony Liguori, (Mon Mar 22, 12:29 pm)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Daniel P. Berrange, (Mon Mar 22, 12:31 pm)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Anthony Liguori, (Mon Mar 22, 12:33 pm)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Daniel P. Berrange, (Mon Mar 22, 1:58 pm)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Olivier Galibert, (Tue Mar 23, 2:46 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Bernd Petrovitsch, (Tue Mar 23, 3:48 am)
Re: [PATCH] Enhance perf to collect KVM guest os statistic ..., Arnaldo Carvalho de Melo, (Tue Mar 23, 6:15 am)
Re: [PATCH] Enhance perf to collect KVM guest os statistic ..., Arnaldo Carvalho de Melo, (Tue Mar 23, 7:10 am)
Re: [PATCH] Enhance perf to collect KVM guest os statistic ..., Andi Kleen, (Tue Mar 23, 7:20 am)
Re: [PATCH] Enhance perf to collect KVM guest os statistic ..., Arnaldo Carvalho de Melo, (Tue Mar 23, 7:29 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Javier Guerra Giraldez, (Tue Mar 23, 12:05 pm)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Daniel P. Berrange, (Wed Mar 24, 8:26 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Arnaldo Carvalho de Melo, (Wed Mar 24, 10:47 am)
Re: [RFC] Unify KVM kernel-space and user-space code into ..., Arnaldo Carvalho de Melo, (Wed Mar 24, 11:27 am)