On Tuesday 24 October 2006 20:41, Bill Davidsen wrote: > Chase Venters wrote: > >Greetings, > > I was just testing a server I was about to send into production on > > kernel > >2.6.18.1. The server has three SCSI disks with "md1" set to a RAID1 with 2 > >mirrors and 1 spare. > > I have to ask, why? If the array is mostly written you might save a bit > of bus time, but for reads having another copy of the data to read > (usually) helps the performance by reducing wait for read occurences.
The main idea is to not exercise the spare as much as the other disks. All three disks are from the same lot. Having three disks fail at once is admittedly unlikely, but keeping one disk as a spare rather than full mirror should probably reduce the wear on that disk so if there is some manufacturing defect the third drive wouldn't be as close to failing and could hopefully keep the box online until someone makes it to the datacenter to do a swap. Thanks, Chase - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
