On Wed, Jun 24 2009 at 11:27am -0400, Mike Snitzer <snitzer@xxxxxxxxxx> wrote: > For some reason I thought you were aware of what Martin had put > together. I assumed as much given you helped sort out some MD interface > compile fixes in linux-next relative to topology-motivated changes. > Anyway, not your fault that you didn't notice the core topology > support.. It is likely a function of Martin having implemented the MD > bits; you got this topology support "for free"; whereas I was forced to > implement DM's topology support (and a few important changes to the core > infrastructure). Got these inverted: > Here is a thread from April that discusses the core of the topology > support: http://marc.info/?t=124055146700007&r=1&w=4 > This post touches on naming and how userland tools are expected to > consume the topology metrics: http://marc.info/?l=linux-ide&m=124058535512850&w=4 > > This post talks about the use of sysfs: > http://marc.info/?l=linux-ide&m=124058543713031&w=4 ... > While I agree that adding these generic topology metrics to 'queue' may > not be the perfect place I don't feel 'bdi' really helps userland > understand them any better. Nor would userland really care. But I do > agree that 'bdi' is likely a better place. > > You had mentioned your goal of removing MD's 'queue' entirely. Well DM > already had that but Martin exposed a minimalist one as part of > preparations for the topology support, see commit: > cd43e26f071524647e660706b784ebcbefbd2e44 > > This 'bdi' vs 'queue' discussion really stands to cause problems for > userland. It would be unfortunate to force tools be aware of 2 places. > Rather than "phase out legacy usage" of these brand new topology limits > it would likely be wise to get it right the first time. Again, I'm OK > with 'queue'; but Neil if you feel strongly about 'bdi' we should get a > patch to Linus ASAP for 2.6.31. > > I can take a stab at it now if you don't have time. On 2nd thought, bdi is inherently tied to mm and doesn't feel 'right'; I'll defer to Martin and Jens on this. Regards, Mike -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
