[imp] Horde/IMP performance and system requirements (50k+ accounts)

[LALOT Dominique]

2009/3/20 Janne Peltonen <janne.peltonen at helsinki.fi>

> Thanks for your answers. A couple comments:
>
> On Fri, Mar 20, 2009 at 09:53:49AM +0100, LALOT Dominique wrote:
> > They notice that there is a big difference on the fact we are using dimp
> > (much more little get).
> >
> > What you can do, is lock the prefs initial_application and use IMP
> instead
> > of DIMP.
>
> We've already done that (partly because our users got very confused with
> DIMP).
>
> > Another point is alarms.php or reminders.php. I noticed during my
> > tests that:
> > reminders.php should be avoided (If you leave it in crontab every 5',
> it's a
> > mistake). Jan said it was just for daily summary. As I locked that, only
> > alarms.php is necessary. But alarms.php also can be a problem, as it runs
> > every 5 minutes and generates tons of selects. Don't remember exactly but
> > more than 10k for 4k users.
>
> So they do. As we've disabled Kronolith completely, we've also disabled
> both alarms and reminders.
>
> On the other hand, there was the one server with Kronolith & co.
> enabled, but I don't seem to find these scripts in any crontabs there,
> either. And I don't remember installing them manually anywhere, either,
> so they shouldn't be doing anything (can't see them in the process list,
> at any time, either).
>
> > Also, you'll have to look at mysql. For big databases, you need special
> > tuning as default values are not good. We are in he way to put (for HA)
> > another mysql server and we will split the access to several servers.
> > (replica)
>
> There was a way to do that? I know that you can create an
> active-passive replica system with MySQL, but didn't know that there's
> an active-active option.


Well, not exactly, you have to install a proxy if you just want to get one
visible host in your setup. In recent version of horde, you can also split
your sql. One server for writes, others for reading. I'm not very good for
mysql setup. My colleague has spent more time on that subject. He will be
back on monday.

My point of view, is that if you are using IMP, the problem should be
elsewhere and not the new release. There is some ajax improvement even in
IMP that should be better for our servers



>
> > As I reread your mail, look at your SQL setup..
>
> There has been much tweaking in there, we read through all possible
> documents abt increasing mysql performance... The mytop util was also of
> much help.
>
> --clip--
> [mysqld]
> #port=3307
> #innodb_force_recovery = 6
>
> datadir=/db/mysql
> socket=/var/lib/mysql/mysql.sock
> # Default to using old password format for compatibility with mysql 3.x
> # clients (those using the mysqlclient10 compatibility package).
> old_passwords=1
>
> #enough connections for all three webmail servers
> set-variable = max_connections=1200
> #default:10, would create trouble
> set-variable = max_connect_errors=10000
> set-variable = log_warnings=2
>
> #new memory parametres -vviitane 27.8.2008
> set-variable = table_cache=3600
> #  vmk/jmp 09.10.2008 lowered the value because of memory trouble
> #set-variable = sort_buffer=128M
> set-variable = sort_buffer=32M
> # vmk/jmp 08.10.2008 lowered the value because of memory trouble
> #set-variable = key_buffer=1024M
> set-variable = key_buffer=256M
> set-variable = join_buffer=128M
> set-variable = max_allowed_packet=16M
> set-variable = query_cache_size=512M
> set-variable = tmp_table_size=256M
>
> innodb_file_per_table
> innodb_buffer_pool_size = 1024M
>
> [mysql.server]
> user=mysql
> basedir=/var/lib
>
> [mysqld_safe]
> err-log=/var/log/mysqld.log
> pid-file=/var/run/mysqld/mysqld.pid
> --clip--
>
> Almost all tables are InnoDB.
>
>
> --Janne
> --
> Janne Peltonen <janne.peltonen at helsinki.fi> PGP Key ID: 0x9CFAC88B
> Please consider membership of the Hospitality Club (
> http://www.hospitalityclub.org)
>



-- 
Dominique LALOT
Ingénieur Systèmes et Réseaux
http://annuaire.univmed.fr/showuser.php?uid=lalot