Re: ioctls, etc. (was Re: [PATCH 1/4] sas: add flag for locally attached PHYs)

Christoph Hellwig
2005-10-22T17:19:43Z

On Sat, Oct 22, 2005 at 11:28:30AM -0400, Sergey Panov wrote:
> It is a mistake to think that you can not do a big rework and keep SCSI
> sub-system stable. You just have to make sure the OLD way is supported
> for as log as it is needed.

No. Rewriting something from scratch is horrible engineering practice.
It's impossible to very huge changes, small incremental changes OTOH
allow easier planning, easier calculation of the risks and cost and most
import better test coverage. There's nothing specific to scsi or linux
kernel code about it. It'd suggest you read:

http://www.joelonsoftware.com/articles/fog0000000069.html

or various similar articles. Full scale rewrites almost never work
out.