В Wed, 24 Jul 2013 13:09:32 -0400 Felix Miata <mrmazda@earthlink.net> пишет:
On 2013-07-24 12:43 (GMT-0400) Andrey Borzenkov composed:
There is memory range below 4G which is reserved for PCI address mapping. Size can be quite significant - if you are using 32 bit system you can lose as much as (or even over) 1G of your memory.
My experience is that reserved space is much closer to negligible: http://fm.no-ip.com/SS/ram-consumed-server01.png
Top knows nothing about this range. This memory is unavailable and invisible for operating system. My notebook has exactly 4GB of physical RAM bor@opensuse:~> cat /proc/mtrr reg00: base=0x000000000 ( 0MB), size= 2048MB, count=1: write-back reg01: base=0x080000000 ( 2048MB), size= 1024MB, count=1: write-back reg02: base=0x0c0000000 ( 3072MB), size= 512MB, count=1: write-back reg03: base=0x100000000 ( 4096MB), size= 512MB, count=1: write-back reg04: base=0x0dff00000 ( 3583MB), size= 1MB, count=1: uncachable 512MB immediately below 4GB can be made available only by remapping them above 4GB address space. So you need kernel with support for addressing of more than 4GB. Which means either 64 bit or PAE. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org