John R Pierce wrote: > well, IF your controller totally screams and can rebuild the drives at > wire speeds with full overlap, you'll be reading 7 * 2TB of data at > around 100MB/sec average and writing the XOR of that to the 8th drive in > a 8 spindle raid5 (14tb total). just reading one drive at wirespeed is > 2000,000MB / 100MB == 20,000 seconds, or about 5.5 hours, so thats about > the shortest it possibly could be done. More likely your looking at 24+ hours, because really no disk system is going to read your SATA disks at 100MB/second. If your really lucky perhaps you can get 10MB/second. With the fastest RAID controllers in the industry my own storage array(which does heavy amounts of random I/O) averages about 2.2MB/second for a SATA disk, with peaks at around 4MB/second. Our previous storage array averaged about 4-6 hours to rebuild a RAID 5 12+1 array with 146GB 10k RPM disks, on an array that was in excess of 90% idle. Rebuilding a 400GB SATA-I array often took upwards of 48 hours. nate