[horde] MYSQL 1040 Too Many Connections.

[Simon Brereton]

Hi

Since I upgraded to 5.0.4 the other day, I've twice had to restart my
MYSQL server (which along with the rest of the box has been running
for about 409 days without an issue).

Now, of course it's possible that this is a not a Horde problem, but
as it's the only thing I've upgraded since the start of December it
seems a reasonable place to start looking.

My current Max_connections is set to 100 (and has been as far as I
know since I installed it.  I don't remember changing this, nor do I
have a record of doing so.

What I see when I look in the mysql server is a growing number of
sleeping connections.

mysql> SHOW FULL PROCESSLIST;
+------+---------+-----------+-----------+---------+------+-------+-----------------------+
| Id   | User    | Host      | db        | Command | Time | State |
Info                  |
+------+---------+-----------+-----------+---------+------+-------+-----------------------+
|   71 | postfix | localhost | Mail      | Sleep   |    0 |       |
NULL                  |
| 721 | root    | localhost | NULL  | Query   |    0 | NULL  | SHOW
FULL PROCESSLIST |
| 730 | horde   | localhost | horde | Sleep   | 1492 |       | NULL
              |
| 731 | horde   | localhost | horde | Sleep   | 1492 |       | NULL
              |
| 765 | horde   | localhost | horde | Sleep   | 1222 |       | NULL
              |
| 766 | horde   | localhost | horde | Sleep   | 1222 |       | NULL
              |
| 824 | horde   | localhost | horde | Sleep   |  946 |       | NULL
              |
| 825 | horde   | localhost | horde | Sleep   |  946 |       | NULL
              |
| 854 | horde   | localhost | horde | Sleep   |  673 |       | NULL
              |
| 855 | horde   | localhost | horde | Sleep   |  673 |       | NULL
              |
| 899 | horde   | localhost | horde | Sleep   |  399 |       | NULL
              |
| 900 | horde   | localhost | horde | Sleep   |  399 |       | NULL
              |
| 925 | horde   | localhost | horde | Sleep   |  121 |       | NULL
              |
| 926 | horde   | localhost | horde | Sleep   |  121 |       | NULL
              |
| 930 | horde   | localhost | horde | Sleep   |    6 |       | NULL
              |
| 931 | horde   | localhost | horde | Sleep   |    6 |       | NULL
              |
| 932 | horde   | localhost | horde | Sleep   |   46 |       | NULL
              |
+-----+---------+-----------+-------+---------+------+-------+-----------------------+
17 rows in set (0.00 sec)

mysql> SHOW STATUS WHERE `variable_name` = 'Uptime';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| Uptime        | 2487  |
+---------------+-------+
1 row in set (0.00 sec)

mysql>
mysql>
mysql> SHOW FULL PROCESSLIST;
+------+---------+-----------+-----------+---------+------+-------+-----------------------+
| Id   | User    | Host      | db        | Command | Time | State |
Info                  |
+------+---------+-----------+-----------+---------+------+-------+-----------------------+
|   71 | postfix | localhost | Mail      | Sleep   |    0 |       |
NULL                  |
|  721 | root    | localhost | NULL      | Query   |    0 | NULL  |
SHOW FULL PROCESSLIST |
|  730 | horde   | localhost | horde     | Sleep   | 2350 |       |
NULL                  |
|  731 | horde   | localhost | horde     | Sleep   | 2350 |       |
NULL                  |
|  765 | horde   | localhost | horde     | Sleep   | 2080 |       |
NULL                  |
|  766 | horde   | localhost | horde     | Sleep   | 2080 |       |
NULL                  |
|  824 | horde   | localhost | horde     | Sleep   | 1804 |       |
NULL                  |
|  825 | horde   | localhost | horde     | Sleep   | 1804 |       |
NULL                  |
|  854 | horde   | localhost | horde     | Sleep   | 1531 |       |
NULL                  |
|  855 | horde   | localhost | horde     | Sleep   | 1531 |       |
NULL                  |
|  899 | horde   | localhost | horde     | Sleep   | 1257 |       |
NULL                  |
|  900 | horde   | localhost | horde     | Sleep   | 1257 |       |
NULL                  |
|  925 | horde   | localhost | horde     | Sleep   |  979 |       |
NULL                  |
|  926 | horde   | localhost | horde     | Sleep   |  979 |       |
NULL                  |
|  951 | horde   | localhost | horde     | Sleep   |  706 |       |
NULL                  |
|  952 | horde   | localhost | horde     | Sleep   |  706 |       |
NULL                  |
|  991 | horde   | localhost | horde     | Sleep   |  432 |       |
NULL                  |
|  992 | horde   | localhost | horde     | Sleep   |  432 |       |
NULL                  |
| 1024 | horde   | localhost | horde     | Sleep   |  159 |       |
NULL                  |
| 1025 | horde   | localhost | horde     | Sleep   |  159 |       |
NULL                  |
| 1036 | horde   | localhost | horde     | Sleep   |    0 |       |
NULL                  |
| 1037 | horde   | localhost | horde     | Sleep   |    0 |       |
NULL                  |
| 1038 | horde   | localhost | horde     | Sleep   |    0 |       |
NULL                  |
+------+---------+-----------+-----------+---------+------+-------+-----------------------+
23 rows in set (0.00 sec)

mysql> SHOW STATUS WHERE `variable_name` = 'Uptime';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| Uptime        | 3347  |
+---------------+-------+
1 row in set (0.00 sec)

Is this a bug?  Is there a recommended value for Max_connections?
I've never had this problem before in 5 years of using Horde.
However, it has a knock-on effect that when Max_connections is reached
postfix can no longer check the validity of the recipient, so mail is
being deferred.

Thanks.

Simon