Change the Query Cache Size Amazon AWS RDSPosted: July 11, 2012
We are running a PHP web site with the Mysql RDS from Amazon, there is a need to change the PHP cache size to make the server run more effectively. Normally this would be done in the my.cnf file but as you know with RDS you use the parameter groups. If you don’t have the RDS tools on your server then look to the another blogg by me for the instructions on getting it up and running Change the max_allowed_packet Amazon RDS
Once you have it working then back here.
You only need to do this part if you did not create a parameter group
rds-create-db-parameter-group NAMEOFGROUP -f DATABASEVERSION -d “My custom database parameter group”
NAMEOFGROUP – If this is a single multi used database, give it a generic name otherwise give it the name of the RDS name
DATABASEVERSION – at the time of writing mysql5.1 mysql5.5
rds-create-db-parameter-group mydbgroup -f mysql5.1 -d “My custom database parameter group”
This has now created the shell to store the parameters such as max_allowed_packet but in this case the query cache size
rds-modify-db-parameter-group NAMEOFGROUP –parameters “name=query_cache_size,value=3048576,method=immediate”
rds-modify-db-parameter-group NAMEOFGROUP –parameters “name=query_cache_type,value=1,method=pending-reboot”
NOTE the pending-reboot, for this setting to take effect the database needs a recycle.
Read up on the query_cache stuff in the MySQL site and forums, this blog is all about how you set things in AWS and not how to tune your MySQL server.
Again you only need to do this if you created the group from scratch
rds-modify-db-instance your-instance-here –db-parameter-group-name NAMEOFGROUP
Substitute you RDS instance name (your-instance-here and NAMEOFGROUP)
You will need to restart the RDS instance to get these settings to take effect.