MySql overload using all memory on the droplet

July 2, 2013 11k views
leo
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leo
Hi, Im migrated a buddypress site to a droplet with 512mb . and im having some issues. The first instalation was fine but when i did the dump / export tables from wordpress, the mysql started to crash. Then i created the swap and it stopped to crash BUT still couldnt use the server. Then i did the changes on my.cnf and apache.conf ( https://www.linode.com/wiki/index.php/MySQL_and_Apache_Optimization_Guide) and i can use it for 1 minute than it overload again but didnt crash This is my free -m total used free shared buffers cached Mem: 491 482 8 0 1 17 -/+ buffers/cache: 464 26 Swap: 511 506 5 The database only have 8mb... its not possible to be eating all the free memory...
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10 Answers
kamaln7 MOD July 2, 2013
The best solution would be upgrading your droplet as it seems like 512MB is not enough for your application stack.

You can try to disable mysql's InnoDB engine as it takes up a lot of RAM: http://stackoverflow.com/questions/11772611/how-to-disable-innodb-in-mysql
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leo July 2, 2013
You sir is a life saver..

I tried the skip-innodb but with no use.. the service wasnt working.. didnt knew that innodb was such a memory hungry
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kamaln7 MOD July 2, 2013
MySQL is probably crashing due to running out of memory. Is everything working fine now?
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leo July 2, 2013
It was but wp_users and some aspect of my buddypress use innodb.. so i turned it on again but with a few changes.. ( http://dev.mysql.com/doc/refman/5.5/en/innodb-data-log-reconfiguration.html)>..

I did some test.. always checking free -m to see the memory use... on the first 10minutes.. all fine.. only using 128mb and no swap (i enter the site.. did some stuff there.. the memory usage got a little bit high but released after) but ... pass the 10 minutes up.. it consume everthing again... what could be happening?
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leo July 2, 2013
total used free shared buffers cached
Mem: 491 485 6 0 0 10
-/+ buffers/cache: 474 16
Swap: 511 509 2


Does my site have all that traffic and i dont know..? pass another 5 minutes and everthing get back to normal...

total used free shared buffers cached
Mem: 491 308 183 0 4 42
-/+ buffers/cache: 261 230
Swap: 511 92 419
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leo July 2, 2013
Seems its not configuration... seems like bad programing.. im checking it...
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kamaln7 MOD July 2, 2013
I don't recommend running a whole LAMP stack with InnoDB enabled on a 512MB droplet as it won't have enough resources and will run out of memory and cause processes to crash.

You should upgrade to at least a 1GB droplet.
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leo July 2, 2013
I upgrade..
total used free shared buffers cached
Mem: 995 871 123 0 0 14
-/+ buffers/cache: 856 138
Swap: 1023 584 439

Im afraid it will consume all again..

... can i have more than 1 swap file?
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kamaln7 MOD July 2, 2013
There's actually 856MB used, the rest are cached. The memory usage looks fine - you shouldn't experience any more crashes.
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leo January 9, 2014
installed memcache and xcache.. oh boy.. huge difference !
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