Kernel Memory Allocation

How kernel memory is allocated and may be controlled in a vPar PA-RISC environment
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4096 - (2048-768) = 2816
2816 = vpar_mem_max which is the user assignable memory allowed which leaves
4096 – 2816 = 1184 MB in the lower 2GB free
By using this process, as long as all of your kernels don’t use up all of the lower 2GB address
space, then you will always have the maximum lower 2GB address space free to either extend
existing vPar kernels or add new vPars. Again, the vpar_mem_max would be the amount of upper
memory address space that could be assigned to the vPars.
C. Create “dummy” vPars
Create "dummy" vPars using the syntax above and ONLY specify memory. The dummy vPars
essentially act as place holders in the lower 2GB memory address space. Yes, you can create
"dummy" vPars that only specify memory resourse. This does take a small amount away from the
overall memory, however, when you need to create a "real" new vPar, the dummy placeholder for
memory can be used for the lower 2GB address space. So when you create a new vPar you
would delete one of the dummy vPars and reuse its base and range specifications for the new vPar.
This way when you create a new vPar you do not have to worry about which existing vPar owns
the extra lower 2GB of address space. You can now pick which vPar you want to reboot in order
to free up the usable vPar memory for the new vPar to use. In addition to aiding in the creation of
new vPars, the dummy vPar can also be used in the case of an existing real vPar needed more
lower 2GB address space. So it would be a good idea to make make the dummy vPar ranges
slightly larger than the existing vPar ranges for lower memory usage.