Created_tmp_files value always showing huge- MySQL RDS performance issue

Hi

I was researching this online and I found this blog post might be related to your case: https://forums.percona.com/t/created-tmp-files-what-is-the-cause/1231

Looks like the increase in the Created_tmp_files resides in the memory and could be caused due to unindexed group by/order by.

From MySQL DOC: https://dev.mysql.com/doc/refman/5.7/en/server-status-variables.html#statvar_Created_tmp_files

Created_tmp_files: How many temporary files mysqld has created.

Most likely related to some queries. Might need your DBAs to take a deeper look.

--> Regarding to the performance, general troubleshooting need to make sure:

1. Instance having enough resources (CPU, Memory, Throughput, these can be reviewed in CloudWatch, Performance Insight)
2. If certain query having performance issue, then need to investigate the query plan, and tune the query.
3. If you suspect something from AWS end causing the performance issue, you may open a support case with us for us to look into storage and host.