On 03/03 02:29 , Les Mikesell wrote: > > CPU load because of RAID5/6 computations on today hardware is marginal. > > RAID5/6 have a performance penalty when compared to other RAID level > > because every single write (or, write IO operation) requires four disk > > IOs on two drives (two reads, and two writes), possibly harming other IO > > operations. > > The seek time for these may be the real killer since you drag the parity > drive's head along for the ride.
The more drives you have in an array, the closer your seek time will tend to approach worst-case, as the controller waits for the drive with the longest seek time for a given operation. Does anyone know anything about synchronizing drive spindles? I've heard of it, and I know it requires drives that are built for it; but never worked with such hardware. -- Carl Soderstrom Systems Administrator Real-Time Enterprises www.real-time.com ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ BackupPC-users mailing list [email protected] List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: http://backuppc.wiki.sourceforge.net Project: http://backuppc.sourceforge.net/
