freebsd stable - Jun 2010 - pde.demotions counts even if pg_ps disabled

HI.

This is 7.3-RELEASE-p1 right after boot.
Looks like pmap_demote_pde is not properly protected w/ pg_ps_enabled.

# sysctl vm.pmap
vm.pmap.pmap_collect_active: 0
vm.pmap.pmap_collect_inactive: 0
vm.pmap.pv_entry_spare: 1421
vm.pmap.pv_entry_allocs: 686316
vm.pmap.pv_entry_frees: 675473
vm.pmap.pc_chunk_tryfail: 0
vm.pmap.pc_chunk_frees: 5392
vm.pmap.pc_chunk_allocs: 5465
vm.pmap.pc_chunk_count: 73
vm.pmap.pv_entry_count: 10843
vm.pmap.pde.promotions: 0
vm.pmap.pde.p_failures: 0
vm.pmap.pde.mappings: 0
vm.pmap.pde.demotions: 5
vm.pmap.shpgperproc: 200
vm.pmap.pv_entry_max: 4264612
vm.pmap.pg_ps_enabled: 0

# uptime
 3:25PM  up 19 mins, 2 users, load averages: 0.00, 0.00, 0.01

-- 
wbr,
pluknet

On Wednesday 30 June 2010 7:28:50 am pluknet wrote:
> HI.
> 
> This is 7.3-RELEASE-p1 right after boot.
> Looks like pmap_demote_pde is not properly protected w/ pg_ps_enabled.
The direct map always uses superpages, but we may demote a superpage in the 
direct map due to conflict caching attributes (all PCI BARs are mapped UC for 
example).

-- 
John Baldwin