From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sven-Thorsten Dietrich <sven@thebigcorporation.com>
Subject: Re: kfree causing high latency on 3.4.4-rt13
Date: Mon, 04 Feb 2013 15:40:55 -0800
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Cc: Thomas Gleixner <tglx@linutronix.de>,
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To: Austin Hendrix <ahendrix@willowgarage.com>
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On Mon, 2013-02-04 at 13:54 -0800, Austin Hendrix wrote:
> An example of what I'm seeing from latencytop is:
> [kfree]                                           7937.6 msec          6.4 %

you are overwhelming folks with data now... but just a few more
questions:

- e.g. what does the RT program you are running do?
- Code snippet that reproduces this issue?
- list of other processes on system.
- system specs; e.g. cpu speed, I am guessing around 8 - 12 Kilo Hz?

Thanks

Sven


> 
> I poked around the kernel source a bit and was pretty stumped by this,
> so I'm glad it's not just me.
> 
> Thanks,
> -Austin
> 
> On Mon, Feb 4, 2013 at 3:49 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
> > On Tue, 29 Jan 2013, Austin Hendrix wrote:
> >> I'm running 3.4.4-rt13 on my systems, and while the realtime
> >> performance is great, I occasionally see non-realtime processes block
> >> for several seconds. Running latencytop, it looks like the kfree
> >> kernel process is the worst offender. Does anyone have advice on how I
> >
> > There is no kfree process. kfree() is a function to release memory
> > allocated by kmalloc.
> >
> > Can you provide the latencytop output please ?
> >
> > Thanks,
> >
> >         tglx
> --
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