[collectd] [PATCH] Random write timeout for rrdtool plugin

[Florian Forster]

Hi Mariusz,

On Tue, Aug 18, 2009 at 12:50:42PM +0200, Mariusz Gronczewski wrote:
> Yeah good point, but that would be probably noticable on very slow
> (like PIII 800 slow) machines with tons of rrd, and then machine would
> run out of disk bandwidth first.

yeah, it's probably not a real problem, but with random numbers you
ought to be careful. In the worst case you'd eat up precious entropy
from the operating system.

> Ive implemented it in attached patch, so far ive been testing it for
> about 1 hour and works pretty well.

Awesome, thanks :) I've pushed it to the master branch of the Git
repository, along with some minor changes from me. For example, I've
optimized away the `random_timeout_mod' variable.

> > So I'd expect the above approach to spread the value quicker.
> 
> Yup, exactly as u said, its much quicker like that.

<http://xkcd.com/54/> \o/

> Im wondering how config variable should be called, name
> "RandomTimeout" dont mean anything useful ("random timeout of what?"),
> maybe TimeoutSpread ? RandomizeTimeout ?

I think “RandomTimeout” is okay, but ”Jitter” or “TimeoutJitter” would
be possible alternatives, too.

Regards,
-octo
-- 
Florian octo Forster
Hacker in training
GnuPG: 0x91523C3D
http://verplant.org/
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