Which disk does innodb_io_capacity impact?
I have MariaDB installed along with my database on an SSD. All of my data files are located on a separate RAID array. I'm trying to understand which disks I need to know the IOPS for in order to set innodb_io_capacity correctly. Should I be using the speeds of my RAID array or the speeds of the SSD that my database and OS are sitting on? Thanks for any help.
Answer Answered by Oli Sennhauser in this comment.
"innodb_io_capacity and innodb_io_capacity_max control the InnoDB background tasks activity, including merging data from the insert buffer and flushing pages."
https://mariadb.com/kb/en/innodb-system-variables/#innodb_io_capacity
The innodb background task flushes dirty blocks from InnoDB buffer pool to disk. These dirty blocks can be blocks from tables or indexes or the double write buffer? Those are located either in ibdata? or in all *.ibd files. So it is relevant where those files are located...
So in your case I think it is the RAID array.
