swapinfo memory field shows different values for 11.11 and 11.23

I have 2 hp-ux PA-RISC systems. One with 11.23 and one with 11.11.
Hp with 11.23 has 16G of physical memory and when I run swapinfo -tam I see:

# swapinfo -mt
             Mb      Mb      Mb   PCT  START/      Mb
TYPE      AVAIL    USED    FREE  USED   LIMIT RESERVE  PRI  NAME
dev        4096       0    4096    0%       0       -    1  /dev/vg00/lvol2
reserve       -     656    -656
memory    16384    2977   13407   18%
total     20480    3633   16847   18%       -       0    -

that the memory Available is 16384. So it is showing 16384 as pseudo-swap.
My 11.11 system has 8Gb of physical memory and when I ran the same command I got:

#swapinfo -mt
             Mb      Mb      Mb   PCT  START/      Mb
TYPE      AVAIL    USED    FREE  USED   LIMIT RESERVE  PRI  NAME
dev        4096       0    4096    0%       0       -    1  /dev/vg00/lvol2
reserve       -    2987   -2987
memory     6291    3483    2808   55%
total     10387    6470    3917   62%       -       0    -

Why is it showing only 75% of my physical memory ( 6291 ) as available (pseudo-swap) and not the total (8Gb) like on the 11.23 system ?
In both systems my swapmem_on parameter is 1.

Thanks
jgb26Asked:
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DanielSVCommented:
Hello,

I can't find any information about this phenomena, but I wouldn't worry, because it uses memory as swap as a last resort (i.e. when disk-swap etc. is full), also - you would never be able to use 100% of your memory as swap, because it, for obvious reasons, need to contain other data as well.

http://docs.hp.com/en/B2355-60105/swapinfo.1M.html
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jgb26Author Commented:
Do you believe that the cause of this can be the system reserves 75% of physical memory on 11.11 and 100% on 11.23 ?
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DanielSVCommented:
I believe it's just a configuration that's changed somewhere.
While you can't tune psuedu-swap (except turning it on and off), HP sure can - so my best guess would be that they changed something.

This contains a pretty good explanation of pseudo-swap: http://docs.hp.com/en/1218/mem_mgt.html#Pseudo-Swap Space

I guess it'll be hard to figure out exactly why it behaves the way it does for you, but as long as everything is working, I wouldn't be concerned about it :)
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jgb26Author Commented:
I found some articles and I believe that this is a question of version.
When you turn swapmem_on on (1) on 11.11 it allocates 75% of physical memory and
when you turn swapmem_on on (1) on 11.23 and 11.31 it allocates 100% of physical memory

thanks for your help
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jgb26Author Commented:
thanks
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jgb26Author Commented:
thanks
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