Showing entries 1 to 3
Displaying posts with tag: open_files_limit (reset)
Maximum Open Files

Recently I was discussing with some colleagues the possibility of consolidating some MySQL servers. While the servers are not heavily loading (averaging less than 1,000 queries a second) they are pretty large in terms of storage requirements. Each server has roughly 200 databases on each with approximatley 50 tables. Thats 10,000 tables per server.  Each server contains up to 1 terabyte of data so if you consolidated servers at a 10:1 ratio you would have 10 terabytes of data, 2,000 databases and 100,000 tables with 10,000 queries per second average load.


Alright, that's a lot. And without testing I don't know if it would work. It probably wouldn't.  But it might. And if it did, it would save the company a significant amount of money.  But, while discussing this,  someone brought up that open files limit might be a problem. Open files limit is the maximum number of files the …

[Read more]
How many files does InnoDB have open?

If you use innodb_file_per_table = 1 and innodb_open_files = X (whatever amount is suitable for your server) there’s no way internal to MySQL for finding out how many IBD files InnoDB actually has open. Neither SHOW GLOBAL STATUS LIKE ‘innodb%’ nor SHOW ENGINE INNODB STATUS provide this information.

Many sites do have a growing number of tables, so you’ll want to know when it’s time to up the number (and potentially also open-files-limit). Solution: sudo lsof | grep -c “\.ibd$”

OurDelta mysqld_safe patch makes it back into MySQL

Last year, Erik Ljungstrom (sensei in the #ourdelta IRC channel on Freenode) created patch for a bug Arjen identified with the handling of (among others) the open-files-limit option; the patch was first included in the OurDelta build of MySQL 5.0.67.

Now, Sun engineer Guilhem Bichot has committed the (modified) patch into the 6.0-maria tree, so it should appear in 6.0 and potentially 5.4. That’s good.

See for details and history.

Showing entries 1 to 3