Re: Linux, ISOFS, multi-extent files: what's the status?
On Sun 10 Jan 2010 10:15:10 NZDT +1300, Bill Davidsen wrote:
> There was another error having to do with reading data at the end of an
> image. Due to read ahead settings a read past end of data occurred and the
> (valid) partial data was not returned to the user program. Might that be
> what you are remembering?
Thanks for mentioning it. Since the mid-90s the kernel produces I/O
errors reading the last blocks of an ISO image from actual disk because
of a read-ahead function. Turning off read-ahead is not sufficient to
prevent this error, turning off DMA is also necessary (presumably that
has its own read-ahead too). This problem because suddenly worse again a
few years ago when DVDs arrived (larger block size, larger read-ahead).
I can't say whether it's ever been fixed completely, I always use a
workaround for my own disks, but haven't seen it much on other disks any
Volker Kuhlmann is list0570 with the domain in header
http://volker.dnsalias.net/ Please do not CC list postings to me.