Hi all,
We tried to upgrade our production server
to beta5 over the weekend, but we noticed much slower response time on
the main page. Previous to upgrade, the mainpage came up in less
than a second, but with Beta 5 (and now Beta 6), it takes 8-12 seconds
(we reverted to xwiki .9).
After moving the database to testing
and doing some debugging, I think I see part of the problem. The main page
shows several news items (ArticleClass items), and it appears that they
are the cause of the slowdown. If I comment out all the calls to
get information about these items ( ie $newsdoc.display("title",
"view", $newsobject) ) the page speeds up significantly (about
1 second per field not retrieved). If I further comment out calls
to $xwiki.getLocalUserName, I get another speed up of about 2 seconds (there
were two calls per news item: for author and creator).
The strange thing is, we saw little
or no performance difference between xwiki .9 and 1 with our test databases,
but copy the production database to testing and we see it. If we
use xwiki .9, it's fast again.
We had previously added an extensive
set of indexes to the mysql database to improve performance in .9, but
dropping/changing/recreating them had no significant effect.
I've tried many debugging steps such
as turning on hibernate debug and xwiki debug, and can't see any unexpected
exceptions on database upgrade., and there's nothing unexpected in xwiki.log.
The database is large-ish, 656M, but
601M of that is attachments, and deleting the entire contents of xwikiattachments
and xwikiattachment_content has no effect. We have 1300 users listed
on the users page, but I have not tried deleting some yet.
Disabling stats had no impact on performance.
I'm testing on Gentoo Linux, with IBM
JDK 1.5, Tomcat 5.5, and MySQL 5.
Any ideas about where to start debugging?
-Tom
--
Tom Kliethermes
eSupport Initiatives
IBM Information Management
(913) 599-7240 Fax: (913) 599-8590
http://www.ibm.com/software/data