Nagios Support Forum

Hi,

We use an offloaded MySQL server. I noticed in the https://assets.nagios.com/downloads/nag ... Server.pdf document a section about recommended settings:

The following parameters are OPTIONAL however they are implemented as part of a default Nagios XI installation and hence it would be beneficial to also implement on the offloaded DB server:
innodb_file_per_table=1
query_cache_size=16M
query_cache_limit=4M
tmp_table_size=64M
max_heap_table_size=64M
key_buffer_size=32M
table_open_cache=32

When we oflloaded our MySQL a few years back these settings weren't mentioned in the documentation at time but I am hoping to implement them now.

I'm not a MySQL expert but I was able to check the settings we currently have set on our MySQL server:

innodb_file_per_table=0
query_cache_size=0
query_cache_limit=1M
tmp_table_size=16M
max_heap_table_size=16M
key_buffer_size =134M
table_open_cache=400

Most of the parameters I'd be increasing to the recommended settings but I just wanted to get any opinions on the last two key_buffer_size and table_open_cache. I'd be decreasing these to the recommended settings. I do not know what they mean and I just wanted to get some opinions if it would be safe for me change them to the recommended settings.

Any advice would be much appreciated.

Our recommendations are not "set in stone". These are just "guidelines" per se. The values that you set for key_buffer_size and table_open_cache would depend on your specific environment, and available resources on the server.

I would not recommend decreasing these values before reading a bit more on the topic:

https://dev.mysql.com/doc/refman/8.0/en ... uffer_size

https://dev.mysql.com/doc/refman/5.6/en ... open_cache