Gentoo Archives: gentoo-user

From: Pandu Poluan <pandu@××××××.info>
To: gentoo-user <Gentoo-user@l.g.o>
Subject: [gentoo-user] How to determine 'Least Common Denominator' between Xen(Server) Hosts
Date: Wed, 14 Aug 2013 05:18:50
1 Hello list!
3 My company has 2 HP DL585 G5 servers and 5 Dell R... something servers. All
4 using AMD processors. They currently are acting as XenServer hosts.
6 How do I determine the 'least common denominator' for Gentoo VMs (running
7 as XenServer guests), especially for gcc flags?
9 I know that the (theoretical) best performance is to use -march=native ,
10 but since the processors of the HP servers are not exactly the same as the
11 Dell's, I'm concerned that compiling with -march=native will render the VMs
12 unable to migrate between the different hosts.
14 Note: Yes I know the HP servers are much older than the Dell ones, but if I
15 go -march=native then perform an emerge when the guest is on the Dell host,
16 the guest VM might not be able to migrate to the older HPs.
18 Rgds,
19 --