Re: fine tuning squid.conf in 1.2.beta22

George Michaelson writes:

>
>Duane, I think based on what we're seeing down a reasonably lightly loaded
>ethernet to two parent caches (somewhat heavily loaded) that the two variables
>neighbour_timeout and dead_peer_timeout should be at least doubled, to remove
>the 'Detected DEAD / Detected ALIVE' sequence in the cache.log.

The dead_peer_timeout can affect the alive/dead reporting, but I think
the neighbor_timeout can not.

Also, now in 1.2 the neighbor_timeout is calculated dynamically (unless
you override it with a fixed value). In the new scheme the (dynamic)
timeout is twice the average of the average RTTs for all (alive)
neighbors who you sent a query to. This doesn't work so well when one
neighbor has a very high RTT compared to others. Arguably, we should
use the max of the average RTTs instead.

>You may want to add some comment to the .conf about what the hold-dead time is
>so its clear what the shape of the sawtooth will be. Is there an explicit
>variable for the dead-time I've missed?

The dead_peer_timeout is probably overloaded and the algorithm is
kind of complicated.
>
>Could the -DNO_CACHE_ACL be elevated to configure --enable/disable status?
>Jointly with this, I think the no_cache options should be enabled by default,
>and the two associated
>
> #acl QUERY urlpath_regex cgi-bin \?
> #no_cache deny QUERY
>
>made live defaults.
>
>cheers
> -George
>--
>George Michaelson | DSTC Pty Ltd
>Email: ggm@dstc.edu.au | University of Qld 4072
>Phone: +61 7 3365 4310 | Australia
> Fax: +61 7 3365 4311 | http://www.dstc.edu.au
>

Duane W.

--
wessels@nlanr.net                           Think Globally, Cache Locally.