[arch-general] Mariadb eats system ressources

[Leonidas Spyropoulos]

On 09/10/14, rumpelsepp at sevenbyte.org wrote:
> Hi,
> 
> after struggling with this problem for one week I have finally decided
> to post on the arch list for getting some help. I have a very strange
> problem with mariadb from the official repos.
> 
> I run a usual LAMP stack (apache, php-fpm, mariadb) on archlinux. Since
> one week (or so) I have realized a very strange behavior: One mariadb
> process stucks on 100 percent CPU usage. I am not able to figure out
> what's going on. Restarting mariadb fixes the problem for a few hours.
> Here is a list of a few debug outputs [1]; I have put it in my pastebin
> because my email client would wrap the text at 80 chars. If you need
> even more information I can update the paste.
> 
> The mariadb status page shows about 6,5 queries per second (!) and I
> don't know where this comes from. I have disabled remote access with
> "skip-networking" (mysql port is closed) and the PROCESSLIST does only
> show one process. I thought it might be an DDoS attack on a website but
> no apache access-log grows unexpectedly. Even after stopping apache
> mariadb stucks on 100 percent cpu usage.
> 
> I figured out that there are listed a lot of connections in the output
> of "show status like 'Con%';". Last hour I even had about 5000
> connections but there are no appropriate queries visible in the general
> log. The general log lists the wordpress queries which are executed when
> I click on my homepage. Everything looks fine; the cpu usage does not!
> Do you have any ideas what I can do to figure out what's going on with
> my mariadb? 
> 
> Thanks in advance!
> 
> Stefan 
> 
> [1]: http://snippets.sevenbyte.org/8/raw/

Can you share your my.cnf and a few information on your databases you
host on the mariadb server?

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