Request for test: Concurrent l1 allocated

[Mark Tinguely]

There are about 35 static l1 page tables allocated per 64MB of RAM.  I 
was curious how many of the static allocated level 1 page tables are 
really being used in a real environment.

I would appreciate it if the following patch was compiled into your next 
kernel:

 http://www.tinguelys.info/mark/freebsd/pmapInUse.diff

The amount of RAM that you have and environment (embedded, mini-server, 
etc) would help. The results can be gathered with the command:

 $ sysctl vm.pmap.pmap_l1u vm.pmap.pmap_l1s vm.pmap.pmap_l1m

vm.pmap.pmap_l1u is the total number of level 1 page tables allocated 
since rebooting.
vm.pmap.pmap_l1s is the number of times the level 1 page tables that had 
to share with an existing l1 pagetable.
vm.pmap.pmap_l1m is the max number of level 1 pagetables at any given time.

--Mark Tinguely