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4 Replies Latest reply: May 15, 2012 5:24 PM by 896905 RSS

Memory allocations

896905 Newbie
Currently Being Moderated
Hi,

Anyone know what the sys memory allocations are for?

S# ldm list-devices -a memory
MEMORY
PA SIZE BOUND
0xa00000 32M sys
0x2a00000 96M sys
0x8a00000 374M sys
0x20000000 2G primary
0xa0000000 18G ldom1
0x520000000 18G ldom2
0x9a0000000 18G ldom3
0xe20000000 7680M


I was hoping to create another ldom with 8G of memory but only 7680M can be allocated.

Thanks,
Paul.
  • 1. Re: Memory allocations
    799794 Newbie
    Currently Being Moderated
    Those are memory blocks used internally by the virtualisation software - typically the Hypervisor (and they can't be freed up for use by guest domains)
  • 2. Re: Memory allocations
    896905 Newbie
    Currently Being Moderated
    Thanks Liam.

    I've noticed that these sys allocations are consistent for the same hardware.

    eg
    T3-1 it is 502M (I have 6 of these and it is the same on all)
    5220 it is 128M (I have 2 of these and it is the same on all)

    Is this documented somewhere?

    Regards,
    Paul.

    Edited by: 893902 on 10/05/2012 17:50
  • 3. Re: Memory allocations
    799794 Newbie
    Currently Being Moderated
    The amount of memory used is not documented anywhere as it's an implementation detail and liable to vary. You could possibly assume that the value on a platform is a lower bound but there would be no guarantees that some extra memory would not be allocated, if needed, depending on the config.
  • 4. Re: Memory allocations
    896905 Newbie
    Currently Being Moderated
    I have had confirmation from Oracle that any free memory can be allocated to guests.

    Whatever free memory exists can be allocated to guests. I guess that means the hypervisor will not try to claim any additional memory.

    Regards,
    Paul.

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