Well I found the problem with this and I thought I'd let everyone know for
the sake of posterity.
I found that this problem did not occur on my non-SMP machines, so I played
around and found that the HotSpot server behaves wierd with SMP. Switching
to pure interpretted mode fixes the problem.
It wasn't Orion... <phew>
-----Original Message-----
From: Aaron Tavistock [mailto:[EMAIL PROTECTED]]
Sent: Monday, March 26, 2001 12:11 PM
To: Orion-Interest
Subject: RE: Performance problems (More Info).
JVM Settings -- My normal settings are "-server -Xincgc -Xms128m -Xmx384m".
I've tried playing around with different JVM options including turning off
server, using normal gc, running in interpreted mode, running in classic
mode, et al. I even tried running under JDK1.2.2. While these definately
effect performance in dramatic ways, none seems to fix this problem.
Garbage Collection -- I tried watching the heap by turning on verbosegc, and
the pauses do not appear to be timed with a full gc. So thats not it
either, definately a good thought though...
DB Server -- The DB server itself is performing fine, CPU and memory
utilization is low. The database is completely accessable via sqlplus or an
alternative app while these pauses occur.
Connection Pooling vs Orions DataSource Manager -- Interestingly the
problem seems to go away when I turn off Orions datasources, and run with a
third party ConnectionPool manager (such as BitMechanic). While this
fixes my immediate problem it will prevent me from using Orion as an EJB
container, which is not good.
> -----Original Message-----
> From: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED]]On Behalf Of Aaron
> Tavistock
> Sent: Monday, March 26, 2001 1:09 PM
> To: Orion-Interest
> Subject: Performance problems...
>
>
> I've been working on getting Orion running in a production
> environment for a
> little while now and just when I thought everything was working
> fine I go to
> push to production and something load/volume related is creating massive
> slowdowns.
>
> Basically every 250 database accesses or so there is a long pause
> (20 to 60
> second), where nothing occurs. During this pause the CPU load *drops* to
> practically nothing and our entire site is frozen. I'm not sure exactly
> where the problem exists; it could be our code, our
> configuration, or even a
> bug in Orion.
>
> The environment is Redhat 6.2, JDK1.3, Oracle 8i. Its a pure
> J2EE app, but
> we're not using EJB. I initially thought it might be a memory issue, but
> I've played with the JDK heap size and carefully watched memory
> utilization
> and thats also not the issue. I even considered that maybe
> Evermind/IronFlare might have a throttle (to push you to get a
> license) so I
> put one of our production licenses on the QA box.
>
> I've since gotten a load tester and can reproduce the problem. Oddly, it
> only happens on pages which require database access. Even more
> interesting
> is that it occurs more frequently on pages which utilize more than one
> connection. But thats about as far as I can narrow it. I've tried the
> 8.15 and 8.17 type4 jdbc drivers from oracle and we've tried Oracles
> ConnectionCacheImpl and Orions XADataSource implimentation, both show the
> same behavior (though both are using the Oracle Driver). I've also tried
> Orions jdbc debug and it shows nothing of interest.
>
> So far I've put about a week straight into finding it, and I've just about
> run out of ideas. I'd really be appreciative if anyone has any good
> suggestions on where to look. ANyone seen behavior like this before?
>
>
