g...@lexort.com (Greg Troxel) writes: >Ah, interesting point. I find this confusing, because I thought an >uncorrectable read error would, for disks I've dealt with, cause the >sector to be marked as permanently failed and pending reallocation.
It is. Doesn't mean that further read attempts aren't honored. >I also didn't realize that wd(4) would issue aother read when there is a >failure, but maybe that's in zfs glue code. ZFS also seems to do a retry by itself, so you have wait the wd retries twice. On Solaris, ZFS can issue a request with the B_FAILFAST flag to instruct the driver to not attempt retries on its own.