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Re: extent-patch and overview of what is supposed to follow

On Wed, Apr 06, 2011 at 05:29:18PM +0100, Mindaugas Rasiukevicius wrote:
> Manuel Bouyer <> wrote:
> > <...>
> > - I'm not sure you want to have dtrace running on a production server.
> > 
> > KMEMSTATS is more than pure debugging purpose, it also helps with
> > tuning, and figuring out temporary overload.
> DTrace was *designed* as suitable for production systems.
> It does not require to compile a debug kernel, which requires reboot and

not an issue: I compile it when I install or upgrade the system, so it's not
an extra reboot

> may be expensive to run.

I've not noticed any difference with KMEMSTATS for me.

> Unlike other debug facilities, dynamic probing
> does not change the function body - it is binary patching of entry/exit
> points and it is only temporarily while probing.

The point it: I don't want probes to be temporarily. When you notice a
problem it's too late to start the probe.

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference

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