Mysql – thesql checking permission takes a long time

I would not worry about application performance with 1 billion rows on a machine that can keep the indexes in memory. If you are serious about reaching 1 billion rows, you first have to do some math:

• What is your record size, and multiply it by 1 billion?
• Next, you need to compute the size of the indexes (more than one index, I'm guessing), and add that on.
• Do you have transactional requirements that you want to have row-level locking for?
• Is this an append-heavy table, or a read heavy table?

Next, move into your application uptime requirements.

• How are you going to back up 1B rows?
• How are you going to deal with a corrupt 1B row table?
• How often will you need to run an OPTIMIZE TABLE?
• How are you going to deal with doing a schema change against a 1B row table? (Adding an index on a 35 million row table on a 2gh dual core box with 2gb ram took me 45 minutes recently.)

I would worry more about the data lifecycle and data management of a multi-gigabyte table file of that magnitude before worrying about performance. With replication, you can make up a lot of the performance. Keeping the data sane and restoring from even small disasters (like corruption induced from bad ram) is more likely going to trouble you first.

I would also encourage you to take the table you have -- and add 1B rows of test data to it. This is extremely insightful to watch what happens to your system. Run some EXPLAINs on your queries against this new huge dataset. Time how long it takes to backup, and restore. You might need to adjust some requirements.

This is an interesting article about 1 billion rows in mysql.

The answer, apparently, was 1 hour, 20 minutes. I'm not sure if that's a "normal" time or if it was delayed by some inefficiency in my setup.