Joomla site extremely slow

[pmeenan]

The first byte time is kind of a black box from the outside so we can't provide a lot of direct visibility. I can say that it's not a redirect though. 90% of the time the first byte performance issues in joomla or wordpress are because of database queries (a lot of them and sometimes slow). The other 10% usually come from back-end requests to external services.

You can start by looking at your database slow query log to see if there are any common slow queries that can be helped by adding a database index. Beyond that it usually requires instrumenting the server code or experimentation with turning things on and off to see where the issue is.

If you have access to modify the php install then tools like New Relic or Dynatrace can be really helpful by telling you exactly where the slow code or queries are (I know New Relic has a free trial period, not sure about Dynatrace).