Re: Possibility for a parallel relaxed RAID?

On Thu, 18 Mar 2010 15:01:44 -0400
Berkey B Walker [off-list ref] wrote:

There maybe many folks out there who want to use RAID on their personal, 
non-production systems.  Assuming access and thru-put values are not 
critical a problem might be "You can't use Desktop drives for RAID".  
Which, I think, most of us know is not really true, but - - If the 
timing issues were to be relaxed, allowing the drive to fix itself, 
before being kicked by the md process, might not the average Joe be 
better served?  There is a big difference between going a mile and 
buying a commodity drive, and being "up" in an hour vs. finding a 
working system, going online, paying price+, and getting/paying fast 
shipping. Which might resolve the issue in days instead of hours.

Any possibility of a parallel, less critical to drive response, release 
of md?  Or a patch to allow same?

This is not a function of 'md'.  md has no timeouts for drives responding.
It just submits a request and waits for a success/fail reply.

It may be a function of the lower level SATA/SCSI/FC/whatever driver.  You
would do better to ask the developers of those drivers, maybe start with the
maintainer of libata.

NeilBrown