MySQL processes - quickly rising

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villieb
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MySQL processes - quickly rising

Post by villieb »

Morning,

I noticed this morning that Cacti wasn't logging any data in any of my graphs. I couldn't SSH to the server. I managed to get console access to the server and saw some errors (I didn't note them down :oops: )

Looking at the MySQL Process List, I am seeing right now, 112 rows of

| 455 | cacti | localhost | cacti | Sleep | 4 | | NULL |
| 459 | cacti | localhost | cacti | Sleep | 4 | | NULL |
| 461 | cacti | localhost | cacti | Sleep | 4 | | NULL |
| 463 | cacti | localhost | cacti | Sleep | 0 | | NULL |
| 470 | cacti | localhost | cacti | Sleep | 2 | | NULL |
| 471 | cacti | localhost | cacti | Sleep | 2 | | NULL |
| 473 | cacti | localhost | cacti | Sleep | 2 | | NULL |
| 475 | cacti | localhost | cacti | Sleep | 0 | | NULL |
| 478 | cacti | localhost | cacti | Sleep | 0 | | NULL |

One of the colomns, time, is as high as 1619...

Is this normal?
villieb
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Re: MySQL processes - quickly rising

Post by villieb »

I now have 151 rows after checking the processlist...
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phalek
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Re: MySQL processes - quickly rising

Post by phalek »

What's the overall status of the server:

Diskspace ( df -h )
Processes ( ps -efwww )

Did you try a restart of mysql ?
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villieb
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Re: MySQL processes - quickly rising

Post by villieb »

Diskspace:
/dev/mapper/nhs--cacti-root 108G 2.8G 99G 3% /
udev 486M 4.0K 486M 1% /dev
tmpfs 198M 256K 198M 1% /run
none 5.0M 0 5.0M 0% /run/lock
none 495M 0 495M 0% /run/shm
/dev/sda1 228M 50M 167M 23% /boot

Processes:
Attached in process.txt

I did try restarting the sql process but the number of entries grow quickly...
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processes.txt
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phalek
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Re: MySQL processes - quickly rising

Post by phalek »

It seems like the poller is being called either too often, or hangs.

Can you check /var/log/cacti/poller-error.log for any issues ?
Greetings,
Phalek
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villieb
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Re: MySQL processes - quickly rising

Post by villieb »

localadmin@nhs-cacti:/var/log/cacti$ sudo tail poller-error.log
PHP Warning: mysql_pconnect(): Too many connections in /usr/share/php/adodb/drivers/adodb-mysql.inc.php on line 383
PHP Warning: mysql_pconnect(): Too many connections in /usr/share/php/adodb/drivers/adodb-mysql.inc.php on line 383
PHP Warning: mysql_pconnect(): Too many connections in /usr/share/php/adodb/drivers/adodb-mysql.inc.php on line 383
PHP Warning: mysql_pconnect(): Too many connections in /usr/share/php/adodb/drivers/adodb-mysql.inc.php on line 383
PHP Warning: mysql_pconnect(): Too many connections in /usr/share/php/adodb/drivers/adodb-mysql.inc.php on line 383
PHP Warning: mysql_pconnect(): Too many connections in /usr/share/php/adodb/drivers/adodb-mysql.inc.php on line 383
PHP Warning: mysql_pconnect(): Too many connections in /usr/share/php/adodb/drivers/adodb-mysql.inc.php on line 383
PHP Warning: mysql_pconnect(): Too many connections in /usr/share/php/adodb/drivers/adodb-mysql.inc.php on line 383
PHP Warning: mysql_pconnect(): Too many connections in /usr/share/php/adodb/drivers/adodb-mysql.inc.php on line 383
PHP Warning: mysql_pconnect(): Too many connections in /usr/share/php/adodb/drivers/adodb-mysql.inc.php on line 383

That line in the adodb-mysql.inc.php contains:

Code: Select all

if (ADODB_PHPVER >= 0x4300)
                        $this->_connectionID = mysql_pconnect($argHostname,$argUsername,$argPassword,$this->clientFlags);
                else
                        $this->_connectionID = mysql_pconnect($argHostname,$argUsername,$argPassword);
Thanks
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phalek
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Re: MySQL processes - quickly rising

Post by phalek »

Edit your /etc/my.cnf file and add a line like the following to it:

Code: Select all

max_connections = 250
then restart your mysql server. and check the logfile and processes again.
Greetings,
Phalek
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villieb
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Re: MySQL processes - quickly rising

Post by villieb »

Thanks - I've edited the file /etc/mysql/my.cnf

So far, the processes within mysql is up at 61 rows...

I'm not seeing the errors as before in the poller log file...

Fingers crossed...
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phalek
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Re: MySQL processes - quickly rising

Post by phalek »

Ok,

If you can, maybe a system restart (or manually kill to the spine/poller processes ) to get rid of these "zombies" would be fine.
Greetings,
Phalek
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villieb
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Re: MySQL processes - quickly rising

Post by villieb »

I've just restarted the server... output from the show processlist is empty (apart from the show processlist process)....

Lets see how this gets on now
villieb
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Re: MySQL processes - quickly rising

Post by villieb »

Up at 33 rows when looking at the mysql processlist
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phalek
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Re: MySQL processes - quickly rising

Post by phalek »

Are there still errors in the poller-error.log showing up ?

You could as well check if there are any error messages from mysql or in your syslog.
Greetings,
Phalek
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DrLightman
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Re: MySQL processes - quickly rising

Post by DrLightman »

Hello, I'm sorry for the gravedig, but I'm experiencing the very same behaviour described here and since it's 3 years old at least, I suppose it's still around.

The more the sysadmin keeps the tool open in the browser, the more mysql connections/processes spawn and don't properly close. They actually fill in the connections of the webserver and may cause other clients/processes to fail to connect in the end.

Image

Do you think of any workaround to let it close those connections properly or maybe use one connection only.

Thank you.
DrLightman
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Re: MySQL processes - quickly rising

Post by DrLightman »

Hello?
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phalek
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Re: MySQL processes - quickly rising

Post by phalek »

Do you have any plugins installed, if yes, which ones and version ?
Greetings,
Phalek
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