VMM page replacement tuning
The memory management algorithm tries to keep the size of the free list and the percentage of real memory occupied by persistent segment pages within specified bounds.
These bounds, discussed in Real-memory management,
can be altered with the vmo command, which can
only be run by the root user. Changes made by this tool remain in
effect until the next reboot of the system. To determine whether the vmo command
is installed and available, run the following command:
# lslpp -lI bos.perf.tune
Executing the vmo command with the -a option
displays the current parameter settings.
Note: The vmo command
is a self documenting command. You might get different output than
the sample output provided here.
# vmo -a
ame_cpus_per_pool = n/a
ame_maxfree_mem = n/a
ame_min_ucpool_size = n/a
ame_minfree_mem = n/a
ams_loan_policy = n/a
enhanced_affinity_affin_time = 1
enhanced_affinity_vmpool_limit = 10
esid_allocator = 1
force_relalias_lite = 0
kernel_heap_psize = 65536
lgpg_regions = 0
lgpg_size = 0
low_ps_handling = 1
maxfree = 1088
maxperm = 843105
maxpin = 953840
maxpin% = 90
memory_frames = 1048576
memplace_data = 0
memplace_mapped_file = 0
memplace_shm_anonymous = 0
memplace_shm_named = 0
memplace_stack = 0
memplace_text = 0
memplace_unmapped_file = 0
minfree = 960
minperm = 28103
minperm% = 3
msem_nlocks = 0
nokilluid = 0
npskill = 1024
npswarn = 4096
num_locks_per_semid = 1
numpsblks = 131072
pgz_lpgrow = 2
pgz_mode = 2
pinnable_frames = 781272
relalias_percentage = 0
scrub = 0
thrpgio_inval = 1024
thrpgio_npages = 1024
v_pinshm = 0
vm_cpu_thresh = 0
vm_mmap_bmap = 1
vmm_default_pspa = 0
vmm_klock_mode = 2
wlm_memlimit_nonpg = 1