PHP Adodb many sleeping connections

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Already asked the question on stackoverflow but i guess this might be a better place for it.

I’m currently struggeling with a strange problem:
while using adodb as connection layer for php, it leaves many sleeping and unneeded connections behind. wait_timeout is set to 20 but there are still plenty (~100) of sleeping connections due to high load on the system. MySQL Version: 5.5.24-0ubuntu0.12.04.1

Is there a known bug regarding adodb5 and sleeping connections? I’m not using persistent connections! Connection establishment:

$conn = &ADONewConnection($DBTYPE);
$conn->Connect($DBHOST, $DBUSER, $DBPASSWORD, $DBNAME)

Would really appreciate any hints/suggestions how to reduce sleeping connection count.

Machine Setup: two servers with apache2 and lighty, loadbalancer and firewall in front, nfs mount with document root and virtual machine with mysql.

Got a huge amount of connections to the database:

863 <db01>

other machine:

476 <db01>

Strange thing: there are only 3-6 active processes on the database – the other ones are sleeping.

Answer

Okay finally found the problem: vhost document root was on an nfs mount (remote). this mount had some IO issues which provoked apache to “idle” connections until the nfs mount is ready again.

Attribution
Source : Link , Question Author : simplyray , Answer Author : simplyray

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