On Wed, 6 Jul 2005, John Horne wrote:
I am trying to set up MRTG to graph the actual number of current clients
accessing a web cache. I can see from the cachemgr and the SNMP MIB,
that the SNMP entry 'cacheClients' exists and has the comment of 'Number
of clients accessing cache'. However, my understanding is that this is
the number of unique clients accessing the cache since it started.
'unique' being the number of clients with a previously unseen IP
address.
Right.
What we want is literally the number of clients accessing the cache
within a given time period (the MRTG 'Interval') - regardless of whether
they have used the cache before or not.
I do not think this information is collected by Squid.
What should be done is that the client_db should have garbage collection
of inactive entries, making clients who has not been using the cache for
some (configurable) time is forgotten by Squid and not reflected in the
statistics.
My thoughts are that we could do this using the file descriptor entry
'cacheCurrentUnusedFDescrCnt' - the number of unused file descriptors.
Since I know the maximum available number of FD's (8192 in our case), I
can get mrtg to subtract the number of unused FD's, hence resulting in
the number of FD's being used.
Does this sound reasonable?
Not really relevant to the question I think.
Regards
Henrik
