Sorry there's no one manual that will give you all the answers.
have you tuned postgres ?
is it actually slow ?
Dave
On 6-Nov-07, at 9:51 AM, Phillip Mills wrote:
I was rather hoping for a "go here, read this" answer as a starting point instead of loading people down with a bunch of details. Also, I have no evidence that JDBC is doing anything wrong; it was just the next item on my path after determining that there wasn't any application lock silliness. But as a software sanity check: JBoss 4.2.1 with a JBossManagedConnectionPool of 20 (but testing with fewer client threads) PostgreSQL 8.1.9-1.2 postgresql-8.1-407.jdbc3.jar (Linux OpenSUsE 10.2)
You'd have to give us a lot more information than this to help you.
machine specs ? Postgresql version and jdbc version postgresql configuration are you using a db pool ?
Dave
On 6-Nov-07, at 9:09 AM, Phillip Mills wrote:
> I'm just getting started on the process of analyzing performance for > a Java Enterprise application. (The main negative symptom at the > moment is that it doesn't use more than three processors on an eight- > processor system, regardless of load.) > > One of the first things I've noticed out of a number of thread dumps > is that there's about an 80% chance that the stack points to I/O > requests from PGStream.ReceiveChar(). I'm wondering about any hints > or pointers that would help me understand whether that's expected > behavior, or something that needs fixing, or just generally how to > evaluate/improve JDBC performance. > > (Regarding the main problem, none of my threads are reported in a > blocked state, leading to my focus on I/O.)
