Will MySql caching cause performance problems?

Question

I am about to upload my website onto a VPS.

It is a classifieds website, where all data is stored in MySql and Solr.

I wonder if when using MySql:s cache, the server will slow down?

Ie, if somebody makes a search for the first time, and MySql is to cache the query, will the caching make the server slower than if it would not cache anything?

After the caching is done I know things will improve in terms of performance...

But I would like to know if I should even use the cache or not, what do you think?

Thanks

Answer 1

I've never run into a situation where Mysql caching was detrimental to performance. The first time a query is run there is no performance hit when the query is written to Mysql's memory cache.

The only significant resource used when query caching is memory. The more memory you configure Mysql to use the more it will cache.

But to get the real answer you need to test it. Gathering metrics is the only way to get a real answer for your particular situation.

There are a variety of caching techniques, some of which might be more useful than query caching to your particular situation.