I have an AWS RDS t1-micro running MySQL 5.5. It gives me too many connections error. I checked and it allows 34 maximum connections concurrently. What I have read is that i can increase this max value by creating a DB parameter group for this Micro instance.
My confusion is
- Should I increase the max connection value for micro in DB parameter group? or Should i consider upgrading to next RDS level which provides more maximum connections (125)?
- Should I increase max_connections on micro RDS to 125 vs upgrading to RDS small instance?
- Why and What factors should I make the decision on?
Thanks
Best Answer
Each connection carries the load of per-connection buffers as set by these parameters
Changing the number of connections increases the amount of memory each connection can demand to this : (join_buffer_size+sort_buffer_size+read_buffer_size +read_rnd buffer_size) X max_connections
I have written about these before
Jan 03, 2012
: Understanding mysqltuner Recomendations w/ Unused CatalogsApr 24, 2012
: How costly is opening and closing of a DB connection?Feb 01, 2013
: Show processlist / Max concurrent connections seem to max out at 131ANALYSIS
Amazon has to set the number of connections based on each model's right to demand a certain amount of memory and connections
I wrote about this as well : When should I think about upgrading our RDS MySQL instance based on memory usage?
This allows Amazon to do the following:
RECOMMENDATION
Perhaps you should try useing Amazon EC2 where you have no restrictions on access to my.cnf