Originally posted by: BieleckiAP

Hi

I have this one old AIX 5.3 LPAR (5300-12-09-1341) with oracle 10G with 72GB memory running on power7 (9117-MMD). I've noticed recently that lrud process running very heavy, but system still have about 11GB free memory. After closer look, I notice that system allocates so much 64K pages and will not switch them to 4K pages when running low on 4K pages. The  540K 64K pages are used by Oracle since they pinning SGA memory but I can't understand why there is 172K 64K pages there free and system is low on 4K pages making lrud process run nuts :

# vmstat -P all 5

System configuration: mem=73728MB

pgsz            memory                           page                 
----- -------------------------- ------------------------------------
           siz      avm      fre    re    pi    po    fr     sr    cy
   4K  7390464  2143607     2854     0     0     0  1381  29127     0
  64K   717744   545700   172044     0     0     0     0      0     0

   4K  7390464  2143097     4504     0     1     3  1870 103395     2
  64K   717744   545700   172044     0     0     0     0      0     0

   4K  7390336  2146264     2515     0     4    84  2228 138038     4
  64K   717752   545715   172037     0     0     0     0      0     0

   4K  7389696  2146937     2209     0     1     4  2124 117860     3
  64K   717792   545715   172077     0     0     0     0      0     0

   4K  7390336  2152361     2033     0     0     0  2574 111549     3
  64K   717752   545715   172037     0     0     0     0      0     0

   4K  7390336  2147296     2696     0     0     0  1132  51531     1
  64K   717752   545715   172037     0     0     0     0      0     0

   4K  7390080  2143932     2630     0     1     0  1596 107308     3
  64K   717768   545705   172063     0     0     0     0      0     0

# vmo -a
        cpu_scale_memp = 8
 data_stagger_interval = 161
                 defps = 1
   force_relalias_lite = 0
             framesets = 2
             htabscale = n/a
     kernel_heap_psize = 4096
          kernel_psize = 16777216
  large_page_heap_size = 0
          lgpg_regions = 0
             lgpg_size = 0
       low_ps_handling = 1
       lru_file_repage = 0
     lru_poll_interval = 10
             lrubucket = 131072
            maxclient% = 90
               maxfree = 1080
               maxperm = 16231276
              maxperm% = 90
                maxpin = 15247373
               maxpin% = 80
       mbuf_heap_psize = 65536
       memory_affinity = 1
         memory_frames = 18874368
         memplace_data = 2
  memplace_mapped_file = 2
memplace_shm_anonymous = 2
    memplace_shm_named = 2
        memplace_stack = 2
         memplace_text = 2
memplace_unmapped_file = 2
              mempools = 3
               minfree = 960
               minperm = 901736
              minperm% = 5
             nokilluid = 0
               npskill = 12288
             npsrpgmax = 98304
             npsrpgmin = 73728
           npsscrubmax = 98304
           npsscrubmin = 73728
               npswarn = 49152
      num_spec_dataseg = 0
             numpsblks = 1572864
     page_steal_method = 1
          pagecoloring = n/a
       pinnable_frames = 9047005
  psm_timeout_interval = 20000
 pta_balance_threshold = n/a
   relalias_percentage = 0
              rpgclean = 0
            rpgcontrol = 2
                 scrub = 0
            scrubclean = 0
 soft_min_lgpgs_vmpool = 0
      spec_dataseg_int = 512
      strict_maxclient = 1
        strict_maxperm = 0
              v_pinshm = 0
  vm_modlist_threshold = -1
       vmm_fork_policy = 1
    vmm_mpsize_support = 1
    wlm_memlimit_nonpg = 1

Thanks for any help.

Andrew Bielecki