[CentOS] Memory recognition in 6.2

Wed Jun 20 00:10:11 UTC 2012
John R Pierce <pierce at hogranch.com>

On 06/19/12 4:22 PM, Hugh E Cruickshank wrote:
> The reason for the restriction to 32-bit is because of other software
> that we must run that does not work correctly on a 64-bit OS.

fix that other software.   or run in 16GB.
there's no excuse in 2012 for not supporting 64bit, even my budget 
laptop has 8GB of memory and a 64bit OS.

as an example of the problems see this message,
http://www.redhat.com/archives/rhelv5-list/2008-September/msg00194.html
and its various followups...

PAE was a kludge to let 32 bit OS's, normally limited to 4GB max memory 
address more.   the kludge breaks things above 16GB in spite of the 
theoretical 64GB limit enforced by the hardware.


also see this
https://www.redhat.com/resourcelibrary/articles/articles-red-hat-enterprise-linux-6-technology-capabilities-and-limits

EL *4* supported a nasty 'hugemem' kernel that could get you past 16GB 
but only at great overhead.  this caused MANY problems and was 
discontinued in EL5 and 6 32bit systems, where 64bit is the correct 
choice for all modern servers.



-- 
john r pierce                            N 37, W 122
santa cruz ca                         mid-left coast