XF 2.1 Lots of idle "sleep" processes caused DB connections to reach max.

[sajal]

We're facing this strange issue which causes our DB connections to go MAX on AWS instance. I can see at least 200 rows in the "show processlist" command.

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| 24173983 | db_name | XXXXXXXXXXX | db_name | Sleep | 1304 | delayed send ok done | NULL |
| 24174782 | db_name | XXXXXXXXXXX | db_name | Sleep | 1274 | delayed send ok done | NULL |
| 24175041 | db_name | XXXXXXXXXXX | db_name | Sleep | 1265 | delayed send ok done | NULL |
| 24176027 | db_name | XXXXXXXXXXX | db_name | Sleep | 1230 | delayed send ok done | NULL |
| 24176669 | db_name | XXXXXXXXXXX | db_name | Sleep | 1208 | delayed send ok done | NULL |
| 24177398 | db_name | XXXXXXXXXXX | db_name | Sleep | 1159 | delayed send ok done | NULL |
| 24177620 | db_name | XXXXXXXXXXX | db_name | Sleep | 1151 | delayed send ok done | NULL |
............
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Any help from experts? Is it something to worry about..? At least, this causes front-end seems to be VERY slow.

 

[sajal]

Found that we've a mysql wait_timeout set to default 28800 seconds.... @experts what's the optimum value?

 

[bzcomputers]

That is the default setting, it may not be the root of your issues.