Search Results for: how mysql database overload

Why you don’t want to shard.

Note: This blog post is part 1 of 4 on building our training workshop.

The Percona training workshop will not cover sharding. If you follow our blog, you’ll notice we don’t talk much about the subject; in some cases it makes sense, but in many we’ve seen that it causes architectures to be prematurely complicated.

So let me state it: You don’t want to shard.

Optimize everything else first, and then if performance still isn’t good enough, it’s time to take a very bitter medicine. The reason you need to shard basically comes down to one of these two reasons

Speeding up GROUP BY if you want aproximate results

Doing performance analyzes today I wanted to count how many hits come to the pages which get more than couple of visits per day. We had SQL logs in the database so It was pretty simple query:

Unfortunately this query ran for over half an hour badly overloaded server and I had to kill […]

Are PHP persistent connections evil ?

As you probably know PHP “mysql” extension supported persistent connections but they were disabled in new “mysqli” extension, which is probably one of the reasons some people delay migration to this extension. The reason behind using persistent connections is of course reducing number of connects which are rather expensive, even though they are much faster […]