Requests suddenly slow / fine after restart

[Poul-Henning Kamp]

In message <480875C6.60503 at turtle-entertainment.de>, Bjoern Metzdorf writes:

>Recently we had some problems with slow requests. Some static graphic 
>files suddenly took several seconds to load instead of the usual 
>milliseconds. After a restart of varnish everything was fine again and 
>the very same graphic was fast again.

You want to use some tool to graph your system activity so that you can
see what system resource is causing your grief.

Most likely it is disk-I/O, but without data it is impossible to be
sure of that.

A lot of varnish people seem be partial to the "Munin" tool for this.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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