[CentOS] maximum cpus/cores in CentOS 4.1

Thu Sep 8 15:38:38 UTC 2005
Peter Arremann <loony at loonybin.org>

On Thursday 08 September 2005 10:49, Tony Schreiner wrote:
> What is the maximum number of AMD64 cores supported by CentOS 4?
>
> The RedHat page https://www.redhat.com/software/rhel/configuration/
>
> suggests that RHEL 4 AS supports up to 8 AMD64/EM64T logical cpus. Is
> that accurate and does it apply to CentOS 4?
>
> I see a few vendors offering boxes with 8 (dual core) CPU sockets.
> IWILL  for one.
The suggestion of 8 was made mostly because there was no larger x86-64 
platform available at that time. 

Also, the main reason for the limit is scalability. With more cpus comes more 
communications overhead, more congestion on the bus, less memory bandwidth 
for each cpu and so on. How much that effects you depends on your 
application. I remember in the good old days when smp was first added to the 
kernel, people said 2cpu was the max you can have... we ran a few 4way 
systems back then very effectivly simply because our application had only a 
low volume of communications. 

Peter.