Freshly installed mysql 5.5 unresponsive

MySQL & MariaDB Other MySQL® Questions
1

Hi Guys,

I installed via apt-get mysql 5.5 and created following custom config that i placed in /etc/mysql/conf.d/custom.cnf


[mysqld]
#bind-address = 0.0.0.0
innodb_buffer_pool_size = 10G
query_cache_limit = 80M
query_cache_size = 64M
tmp_table_size = 256M
max_heap_table_size = 256M
table_open_cache = 2000
join_buffer_size = 64M
max_allowed_packet=512M

log_slow_queries = /var/log/mysql/mysql-slow.log
long_query_time = 2
#log-queries-not-using-indexes

max_connections = 250

An apache web server in the same network is connecting to this server (roughly 70 max connections) and a couple of times the database would become unresponsive.

Now my fear is that there is something not okay with my config above.
The server has a SSD, 32GB of ram and 4 cores. All tables are InnoDB

Any input would be greatly appreciated.

Thanks in advance!

2

Hi andygee;

You’ll need to do a lot of checking during the issues to see what is going on. I’d check the host server itself to see what the stats look like; CPU usage, memory usage (i.e. is it swapping), and I/O wait percentage. That will tell you if the host itself is having trouble or not.

A more likely case is that things are getting backed up in MySQL itself. So to find that out, you’ll need to run a “show engine innodb status \G” and “show processlist;” while this is happening to see what the InnoDB internals look like.

Once you have that information, you can start to figure out what is really going on. Could be getting hung up on a metadata lock, or you could be hitting async flushing, both of which can bring things to a halt.

-Scott