best timeout defaults

[Dridi Boukelmoune]

Hi Tim,

On Fri, Sep 18, 2015 at 6:36 AM, Tim Dunphy <bluethundr at gmail.com> wrote:
> Hey guys,
>
>  Just wondering what y'all would consider the best / optimal timeout
> settings for varnish servers to contact they're backends. Considering that
> both varnish servers and web servers are in the same datacenter.

There's no such thing as optimal timeout settings IMHO. The fact that
your servers are sitting in the same datacenter is sonething you need
to take into account, but also the behavior of your backends. For
example, if you know that your backend will stream results immediately
you might want to lower the fbto, and if your backends tend to
precompute the response before sending it you might want to lower the
bbto instead.

If you are not familiar enough with the backends implementation
details, the best course of action is probably to be conservative and
measure the response times to find out the expected responsiveness
from the backends.

> Oh and heck. While we're at it, is there a general rule of thumb/best
> practice for this one?
>
>    .max_connections = 800;

Again, it all depends on your backends capabilities.

Cheers,
Dridi