Re: [Lse-tech] Higher level NUMA API ?

[Paul E. M. <pa...@us...>]

On Mon, Mar 13, 2006 at 04:17:19PM +0100, Simon Derr wrote:
> 
> Hi,
> 
> I was reading the minutes of a 'Linux-on-NUMA' meeting of March 2001 (I 
> feel a bit like an archaeologist) and this catched my eye:
> 
> "Subsequent discussion divided NUMA functionality into three groups: 
> 
> (1) changes to improve performance on NUMA for non-NUMA-aware applications, 
> (2) changes to provide simple control of resources and execution as would 
> be needed for benchmarks and the like, and 
> (3) changes to allow more general and declarative control of resources and execution. 
> 
> It would be very nice if the APIs for #2 were a nice subset of those for #3."
> 
> (http://lse.sourceforge.net/numa/older_stuff/meetings/mtg.2001.03.26/minutes.html)
> 
> 
> I think we can say that many kernel-level improvements that have been 
> added since then cover group #1.
> 
> sys_schedsetaffinity(), libnuma and cpusets cover group #2.
> 
> And what about group #3 ?
> 
> Is anyone aware of ongoing work in that direction ?

Some would argue that cpusets covers some of the functionality in #3.

One important step would be to check up on what the performance and
usability benefits of #3 would be.  Today's NUMA machines are much
"flatter" than were a number of the mid-90s machines, so the mileage
one could expect to get from advanced NUMA-support functionality may
well have changed.

						Thanx, Paul