Debian Squeeze e memória disponível (1GB ausente)

Question

aqui eu tenho um servidor dedicado com 12GB de RAM e rodando o Debian Lenny x64.

dmesg | grep Memory
[    0.004000] Memory: 11917152k/12259740k available (2279k kernel code, 333820k reserved, 1022k data, 216k init)

Desde alguns dias, tenho outro servidor dedicado (praticamente o mesmo hardware), mas com o Debian Squeeze x64 (instalado via debootstrap, Kernel 2.6.32-5-xen-amd64)

dmesg | grep Memory
[    1.551510] Memory: 6864620k/8151916k available (3146k kernel code, 1057736k absent, 229560k reserved, 1901k data, 600k init)

o que significa memória ausente? E como posso obter 1GB de RAM de volta?

    

Answer 1

Extraído de Red Hat Bugzilla - Bug 598290 :

absent memory reflects the memory addressing space lost due to memory holes in the memory map. Typically holes are left for PCI space, IO, etc.. Every vendor model system is different, and every system will have a different value reported for the absent memory.

Bottom line: It is not physical memory.