[horde] Horde 3.1: MySQL performance problem

[Marco Pirovano]

Hello,

last week I switched the webmail server of our university from Horde2/IMP3 to 
Horde3.1/IMP4.1.

All seems to be good untill the number of contemporary users reached about 500.
At that point the MySQL db response was VERY slow and we saw the message:

"Fatal Error: can't connect to DB horde_uni".

Our infrastructure is composed of:

* 4 front-end (HP DL360 4 GB RAM, 2 CPU, FreeBSD 6.1) with:
  - Apache 2.0.59
  - PHP 4.4.4
  - eAccelerator 0.9.5
* 1 MySQL server 5.0.27 (HP DL580, 4 GB RAM, 2 CPU, FreeBSD 6.1)
* 1 IMAP server Cyrus 2.2.12 (HP DL580, 4 GB RAM, 2 CPU, FreeBSD 6.1)

who was using the client (Outlook, Eudora or Thunderbird) had no problem.

I tried to adjust MySQL parameter, but without success, so, afther three days
of tentative, I had to rool back to Horde2/IMP3 :-[

We run Horde2/IMP3 for more than 3 years without no problem and with only
one server for both Apache and MYSQL.

My boss told me that he want to use another system, but I'm sure tha Horde
is the best and also the most used, especially in the academic world.

But I have to sove the problem and than to persuade him !

So, I'm asking who is using Horde 3.1 / IMP 4.1, on which infrastructure,
how many contemporary users and if you had the same performance problem and how
do you solved that problem.

Please help me ...

Thank you very much.
ciao,
Marco

* Marco Pirovano
* Universita' Bocconi, Area Sistemi Informatici e Telematici
* Piazza Sraffa 11 - 20136 Milano
* Tel. +39 02 5836.3173  Fax. +39 02 5836.3160  VoIP. 02 5828.3173