users@glassfish.java.net

connection pool monitoring on a cluster

From: Dick Davies <rasputnik_at_hellooperator.net>
Date: Thu, 28 Aug 2008 14:11:06 +0100

I've got a 2 node GF2 cluster and I'm trying to enable connection pool
monitoring on it
(following http://blogs.sun.com/JagadishPrasath/entry/monitoring_jdbc_connection_pool_glassfish
which is a good howto).

Because I'm on a cluster, the server instances use a different
configuration (clustername-config) to the DAS (server-config).
It looks like the admin webapp lets you enable JDBC monitoring for the
clustername-config configuration, but you can only view
things under 'server-config' (i.e. things on the DAS).

I tried the commandline instead and had more luck.
It looks like there's an entry for the pool under each server instance:

gfish$ asadmin list --monitor=true *prod-pool*
inst01.resources.prod-pool
inst02.resources.prod-pool

So my first question is : can I see these values via the admin webapp?

Also, it looks like each server instance has its own copy of the pool,
that's right isn't it
(in my mental model, they were sharing a global pool and checking out
their own connections)?

If I browse around under those entries I can find stats on the
pool(s?) themselves, but they don't seem to add up:

gfish$ asadmin get --monitor=true inst*.resources.prod-pool.numconn*-current

inst01.resources.prod-pool.numconnfree-current = 7
inst01.resources.prod-pool.numconnused-current = 0
inst02.resources.prod-pool.numconnfree-current = 6
inst02.resources.prod-pool.numconnused-current = 0

I expect the database to be failry quiet (I memcache the hell out of
this app) but
both the pools have an initial size of 8 (the default), so I can't
figure out where the other connections are?

Have I missed an entry, or am I just not understanding the values?

Tried the same thing on my desktop
(same version of GFv2 but in developer profile, so everything is under
'server') and it behaved as expected.

-- 
Rasputnik :: Jack of All Trades - Master of Nuns
http://number9.hellooperator.net/