After having badblocks running for 500+ hours on my first set of SAS disks and several searches to see if I could figure out why they were running so slow but coming up empty handed, I finally found a post were someone else was seeing the same thing with some new WD SAS disks and finding that the writeback cache was disabled on them. After enabling it, badblocks went from 8Mbps (he posted it as Mbps, don't know if he meant 'Megabits' or 'Megabytes', but it doesn't really matter - either is...
SAS Disk Writeback cache
SAS Disk Writeback cache
