On 08/14/2013 07:18:41 AM, Pandu Poluan wrote:
Hello list!
My company has 2 HP DL585 G5 servers and 5 Dell R... something
servers. All
using AMD processors. They currently are acting as XenServer hosts.
How do I determine the 'least common denominator' for Gentoo VMs
(running
as XenServer guests), especially for gcc flags?
I know that the (theoretical) best performance is to use
-march=native ,
but since the processors of the HP servers are not exactly the same
as the
Dell's, I'm concerned that compiling with -march=native will render
the VMs
unable to migrate between the different hosts.
Note: Yes I know the HP servers are much older than the Dell ones,
but if I
go -march=native then perform an emerge when the guest is on the Dell
host,
the guest VM might not be able to migrate to the older HPs.
Rgds,
--
Why not compute it yourself?
Do cat /proc/cpuinfo on all machines and compute the intersection of
all "flags"
Then enter something like the following into /etc/portage/make.conf
CFLAGS="-O3 -pipe -msse -msse2 -msse3 -msse4a -m3dnow"
Helmut
