Re: [PATCH] top level scheduler domain for ia64

[Jesse Barnes <jbarnes@engr.sgi.com>]

On Thursday, October 28, 2004 2:29 am, Takayoshi Kochi wrote:
> Our 32way machine still isn't configured well with the overwrapping
> domain partitioning.  CPUs 0-15 belongs to domain (0 1 2 3 4 5 6)
> and CPUs 16-31 belongs to domain (0 1 4 5 6 7), which is assymmetric
> and at least does not reflect the real connection.

Hm, I was afraid of that since the top level domain is only built if the 
system has more CPUs than SD_NODES_PER_DOMAIN * cpus_per_node.  We could 
change that to be a simple if (numnodes > SD_NODES_PER_DOMAIN) instead.

> dmesg of the machine is attached.
>
> The following patch makes the ia64 domain partitioning (maybe Altix
> specific ;) optional and makes the magic number (6) configurable.
>
> What do you think of this?

Maybe a boot parameter would be better for configuring SD_NODES_PER_DOMAIN?  
That would allow a single kernel binary to be configured to run well on many 
types of NUMA systems.  It would also mean you could play with very large 
node domains, with and w/o a top level domain.

Jesse