Developers of Sympa

[Petr Prazak <address@concealed>]

4.5.2001, Olivier Salaun wrote on subject `[sympa-dev] Performance problem':

> You probably need to customize your MySQL configuration.
> With MySQL standard distribution you will find sample config files
> for small to huge databases. Check in /usr/share/mysql (on RH Linux).
> Basically you can customize buffer, stack and cache size.

I have taken the my-large.cnf, will see if it helps.
I'm no db admin :), thanks for pointer.

> What is your hardware profile ? (CPU, Mem, Disk controller)

Pentium III, 550MHz, 512 MB memory, two Seagate ST39236LW (10GB) in RAID 1

> You should first check mysql log file to find out what SQL queries 
> are performed by Sympa. Then try running them using mysql client
> to find out which ones are critical.

It queries the database for a user;

mysql> EXPLAIN SELECT lower(email_user) AS email, gecos_user AS gecos,
password_user AS password, cookie_delay_user AS cookie_delay,
lang_user AS lang FROM user_table WHERE lower(email_user) = 
'address@concealed';

+------------+------+---------------+------+---------+------+--------+------------+
| table      | type | possible_keys | key  | key_len | ref  | rows   | Extra  
    |
+------------+------+---------------+------+---------+------+--------+------------+
| user_table | ALL  | NULL          | NULL |    NULL | NULL | 325143 | where 
used |
+------------+------+---------------+------+---------+------+--------+------------+
1 row in set (0.01 sec)

This query took 4 seconds.

I tried to remove the lower() from where clause:

mysql> EXPLAIN SELECT lower(email_user) AS email, gecos_user AS gecos,
password_user AS password, cookie_delay_user AS cookie_delay,
lang_user AS lang FROM user_table WHERE email_user =
 lower('address@concealed');
+------------+-------+---------------+---------+---------+-------+------+-------+
| table      | type  | possible_keys | key     | key_len | ref   | rows | 
Extra |
+------------+-------+---------------+---------+---------+-------+------+-------+
| user_table | const | PRIMARY       | PRIMARY |     100 | const |    1 |     
  |
+------------+-------+---------------+---------+---------+-------+------+-------+
1 row in set (0.00 sec)

This query took 0.01 seconds.

I see then it would be much better to store the email addresses as
lowecased.

But this doesn't explain what the wwsympa hangs when fetching a page 
/wws/lists

From log:
May  4 15:51:18 willy wwsympa[9902]: [client 193.85.188.248] [user 
address@concealed] do_lists(,)
... [now i wait for a while ]
From process list:
sympa     9902 23.9 28.0 159700 144852 ?     R    15:46   1:27 perl -U 
/home/sympa/bin/wwsympa.fcgi

... After few minutes ...

sympa     9902 53.2 27.9 159700 144336 ?     R    15:46   5:33 perl -U 
/home/sympa/bin/wwsympa.fcgi

[No output]

Is there a way how to debug the wwsympa.fcgi to see what this process
does so long ??


I have also raised the number of fastcgi processes to 25 from 5, to se
if it helps (doesn't seem so).


Best regards,
 Petr Prazak