Strange poor V4 performance after migration


Hi there,

I’ve updated on a dev server a website with a large amount of posts (about 200k + 7m post meta) from V3 to V4. I’ve also updated the server as well (I’m on AWS).

Before it was 1CPU and 2GB of RAM + small RDS.

Since V4 has a separate container for Mariadb I thought I’ll give it a go and drop RDS and use same instance for Mariadb. I took 2CPU and 4GB of RAM EC2 instead.

The result?
V3 website loads in about 1-2 seconds
V4 website loads between 20 seconds and time out of 30s

Anything I’m missing here?


Did you create your website with cache? Site being a bit slower was expected as you moved DB on the server itself, but 20s is too much.

Also, check load on the server and your swap usage. If OS starts swapping due to high memory consumption of DB, this might result in slow page loads.