World of *Nix

For our office products, we are using Amazon Cloud. For the database, we prefer to use Amazon RDS (Aurora). Recently one of our sites was showing lots of error message in sentry.io. The error log shows it was because of MySQL denied to connect for too many open connections. This is when we checked the RDS max_connection limit and found its related to the size of your RDS instance. So we tested the max_connection limit for different size instances. And here is the result:

t2.small:

t2.medium:

r3.large:

r3.xlarge:

r3.2xlarge:

r3.4xlarge:

r3.8xlarge:

Few minutes ago, one of our mysql database table (it’s really a big table) was crashed.
So to repair this i login that server and excute

repair table tablename

But the repair process failed, and i got this output.

test.t1 | repair | error | 13 when fixing table |
| test.t1 | repair | status | Operation failed |

Then i start searching on google. After passing some time i found the reason. Mysql can’t repair that table as there is a trigger on this table. So i tried to drop the trigger

drop trigger triggername

no luck, mysql can’t drop the trigger, as the table was crashed 🙁

Now i studied more and more. At last i got the solution 🙂

REPAIR TABLE tablename USE_FRM

Now the table repair complete successfully. Thanks to Allah as i got the solution in time:)