[horde] addCategory(), horde_categories table, horde.history field memory leak?

[Chris Wopat]

I'm helping to debug a horde installation (HEAD version from late November
2003) that has some severe memory issues. Horde/Imp runs on 3 servers;
html/php are served from a machine w/ 3GB of memory. There typically a few
hundred simultaneous users on at peak times. Frequently over the past few
days the machine has begun paging to swap and crapped out.

Here's the problem. When some users compose and send an email, their apache
process will take ~150MB of memory. Just two days ago it was maxing out at
143MB, so this number is slowly creeping. We've rebooted the server (as well
as restart apache) several times per day, but the large processes always
come back. It doesn't happen to all users, just some. I'm not even sure if
it happens consistently for a single user or not.

After much debugging, I've found the single common link. For the process in
question, a field is always inserted into horde_categories for
horde.history, similar to this:


Jan 07 18:17:19 HORDE [debug] [imp] SQL Query by
Category_sql::addCategory(): INSERT INTO horde_categories (category_id,
group_uid, category_name, category_order, category_data, user_uid,
category_serialized, category_parents) VALUES (155656, 'horde.history',
'imp.emailof at thehordeuser*com.<A1EeIq7-0005iy-RH at recipients.domain.net>',
NULL, '', 'emailof at thehordeuser.com', 0, ':65024') [on line 320 of
"/usr/local/www/docs/secure/horde/lib/Category/sql.php"]


The slowness doesn't appear to be happening while it's being inserted, but
instead just prior to this statement being logged; so possibly when this SQL
is being generated.

Horde is relatively new to me and I've been assisting some other folks to
debug this.

Is there a specific option to turn on (err, off) entries into
horde_categories for horde.history? What exactly ARE these entries?

PHP 4.3.4
Apache 1.3.29
MySQL 4.0.1x

Thanks,
Chris Wopat