Re: Crashed Drive, libata wedges when trying to recover data

Greg Stark
2004-09-04T21:58:35Z

Alan Cox <alan@lxorguk.ukuu.org.uk> writes:

> > Jeff, do we really have to wait 30 seconds for a timeout? If the drive hits an unreadble spot I
> > would have thought it would come back to us with a read error rather than timing out the command.
>
> The drive will retry for a few seconds then fail. The failure now
> generates a SCSI medium error to the core scsi layer and it does like to
> issue a few retries. The default retry count for scsi is probably too
> high for SATA given the drive retries.

Certainly over an hour seems a little excessive:

$ time dd bs=512 count=1 if=/dev/sda4 of=/dev/null
dd: reading `/dev/sda4': Input/output error
0+0 records in
0+0 records out

real 67m59.382s
user 0m0.001s
sys 0m0.002s

bash-2.05b# time mount /dev/sda4 /u4
/dev/sda4: Input/output error
mount: you must specify the filesystem type

real 71m59.322s
user 0m0.000s
sys 0m0.004s
bash-2.05b#

--
greg