cayenne-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Michael Gentry <mgen...@masslight.net>
Subject Performance Issues/Questions
Date Sat, 12 Dec 2009 01:45:57 GMT
We were doing some simple performance tests today at work between
Hibernate and Cayenne.  A lot of the developers are a bit "tired" of
Hibernate and are exploring the idea of Cayenne now, but the project
we are looking at using it on next will be a public and politically
sensitive (our government agency doesn't like us discussing details)
web application and needs decent performance, so we were tasked to do
some basic performance tests against an existing DB.

We configured Cayenne and Hibernate both with 5 DB channels and ran on
the same machine (4-cores, lots of RAM).  I did not use optimistic
locking in Cayenne.  I made sure the DB channels were all open before
running.

Here is the result of our initial tests:

http://spreadsheets.google.com/pub?key=tNytbSdt5wYIRTmTl4L-cCA&output=html

(Hope that link works.)

The 20 indicates 20 concurrent threads (each with a separate DC).  The
5 is 5 concurrent threads (to match the DB channels, each with a
separate DC).  I'll discuss the 5-2 in a minute.

I expected Cayenne to be a little slower since it does more, but some
of the results were particularly surprising.  Especially UpdateIdea20,
which averaged 5.6 seconds to commit a simple name change to the Idea
table (which was a relatively small table -- perhaps 15 or so
attributes).  On most of these you will notice the commit time just
keeps growing and growing.

I thought at first it might just be DC sync, so I did as suggested in:

http://cayenne.apache.org/doc/turning-off-context-synchronization.html

but that didn't seem to have much of an effect (if any).  Then I
started thinking about our tests being fairly simple and they were all
updating the same record repeatedly (which isn't realistic, I know),
so for 5-2 I made sure 5 different records were being updated and
turned off Use Shared Cache for the domain.  That had the biggest
impact, but even for that one the time more than doubles between the
first and fifth threads.  (The JVM in OS X uses all available cores,
so at least 4 of the 5 were able to run concurrently.)

Are there more optimizations that can be done?

Does http://issues.apache.org/cayenne/browse/CAY-554 (mentioned on the
turning off context synchronization link above) still apply to 3.0?

Just looking for some thoughts.  I've never really had to optimize
before because all of my stuff has been smaller-scale before and
certainly less visible.

Thanks!

mrg

PS. At this point, they'd probably use 2.0.4 unless 3.0 is becoming an
official release soon, too.  I just expect 2.0.4 to be even slower.

Mime
View raw message