In the last episode (Aug 21), Jon Drukman said: > Lefevre, Steven wrote: > >I say go with RAID 5, on a controller card. > > Mirroring just gives you backup, and you lose half your diskspace. > > It offers no performance benefit, and actually the computer might > > have to work harder to make sure the drives are in sync. > > that is not true. mirroring gives you double the read speed and half > the write speed. RAID5 gives you less than half the write speed.
Software raid5 gives you around 1/4 the write speed, to be exact. Hardware raid5 with battery-backed cache can completely remove the penalty, by either waiting for an entire stripe of data to flush in one operation, or delaying the extra I/O operations until the disk head happens to be near that block anyway (or until the disk is otherwise idle). Make sure you max out the RAM in your raid card; it's cheap. -- Dan Nelson [EMAIL PROTECTED] -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]