Alex Yurchenko <[email protected]> writes: > I wonder how practicable such setup really is. If one has disk-bound > application, would not he rather use RAID or something to speed up > individual writes than trying to execute writes in parallel hoping that > they get to different drives? I mean acceleration of writes on low level > always works, parallelization would require suitable application profile > and careful distribution of the database on multiple drives. Or are we > talking about multiple RAIDs?
RAID == multiple disks. (You can use multiple tablespaces as well, but RAID (or maybe LVM) is probably the most often used method). And it is not really the writes that are the problems. The problem is the reads that are needed to figure out which writes to do. (Writes are less of a problem, as they can be done asynchroneously). And RAID does _not_ speed up an individual read! It only allows to do more reads in parallel, increasing overall throughput. In my opinion, it is often more interesting to speed up I/O-bound workloads, as they are orders of magnitude slower than CPU-bound workloads. And even a system that is usually CPU-bound can easily show I/O-bound behaviour in some scenarios (like warm-up after server restart). - Kristian. _______________________________________________ Mailing list: https://launchpad.net/~drizzle-discuss Post to : [email protected] Unsubscribe : https://launchpad.net/~drizzle-discuss More help : https://help.launchpad.net/ListHelp
