[squid-users] Time for cache synchronization between siblings

[Sreenath BH]

Hi,

I have a setup with three squid peers (siblings in squid.conf) and
three upstream servers(peers with parent and originserver in
squid.conf).

I am using htcp for the three squid siblings.
How much time does it take for one squid server to 'know' that another
peer has a particular object cached? I see digests exchanged between
the siblings, as logged in cache.log.

I have been able to make a request to one sibling and it resulted in a
sibling_hit.

How I do this test is this:
1. bring up all siblings
2. issue a request to one server (sibling 1)
3. Make sure it is cached in sibling 1
4. Wait for some time (I don't know how long to wait)
5. Make same request to another sibling, say sibling 2
6. Check if it went to upstream server for the request or it was a sibling hit.

My problem is that the sibling hits seem to be random. I am  not able
to figure out exactly
how log it takes for the cache information to propagate to all siblings.

Any information in this regard is appreciated.

thanks,
Sreenath