VMware Cloud Community
kverneland
Contributor
Contributor

VMotion between dual/single AMD SSE3/NON SSE3

We are running ESX 3.0 on DL585, two single core AMD and one dual core AMD. The single core AMD's doesnt support SSE3 and the dual core does.

Running virtual center 2.0. Vmotion between the single core machines works fine, but the dual core is marked as cpu not compatible in VC.

Have read alot of different docs on this topic but still havent found a answer that helps, so the questions are..

1. Is it possible to do VMotion between AMD dual/single SSE3/nonSSE3 ?

2. If so, how ? using ESX3.0 and VC 2.0

3. Is it supported ?

4. If not, will it be ?

Reply
0 Kudos
10 Replies
mstahl75
Virtuoso
Virtuoso

With ESX 3.0 and VC 2.0 the only supported method I know of is to mask the CPU features that aren't shared from the VMs. On a VM Edit Settings > Options > Advanced[/b] under CPU Identification Mask > Advanced[/b] there are places to mask certain features. There is a Legen[/b] option on that screen that will show what options can be put into the mask.

Looking at /proc/vmware/cpuinfo[/b] of each machine should give more clues into what needs changed. You might check out this topic[/url] for some discussion into the matter. That one is about Intel processors though it still should be useful.

Reply
0 Kudos
kverneland
Contributor
Contributor

Here is my cpu info:

pcpu 00

family 15

model 01

type 00

stepping 00

cpuKhz 2199929

busKhz 199993

name AuthenticAMD

ebx 0x00020800

ecxFeat 0x00000001

edxFeat 0x178bfbff

initApic 0x00000000

apicID 0x00000000

pcpu 00

family 15

model 05

type 00

stepping 10

cpuKhz 2396863

busKhz 199738

name AuthenticAMD

ebx 0x00000800

ecxFeat 0x00000000

edxFeat 0x078bfbff

initApic 0x00000000

apicID 0x00000000

If i do a cold migrate from A dual to B single it only changes the CPUID Fn8000_0001_EDX

to -


-


---0 -


-


-


-


-


Is there an easy way of figuring out what other masks i need to change Smiley Happy

Reply
0 Kudos
mstahl75
Virtuoso
Virtuoso

Most people that have been doing this have just tried some settings and tested it out.

I know, when I did cold migrations from 2.5.x to 3.0 that VirtualCenter automatically generated the masks for me. Not sure if it is a cross LUN migration that kicks that masking off or it was only the version change migration though.

Reply
0 Kudos
cryptonym
Enthusiast
Enthusiast

So, am I correct that if one masked out the differences they'd be likely to be vmotionable?

For the above given example, would these masks be likely to work:

ebx -


-


-


--0- -


-


-


-


ecx -


-


-


-


-


-


-


---0

edx ---0 -


-


-


-


-


-


-


It looks to me like, this (or using F instead of 0 maybe) would make the featureset identical between the procs. Am I correct?

Is there a whitepaper on this, or at least a cross processor reference on the flag bits. I'd hate to need to decipher all the various cpu models docs myself. Hopefully VMWare has this available.

Thanks,

Warren

Reply
0 Kudos
mstahl75
Virtuoso
Virtuoso

To my knowledge there isn't a document provide by VMware at this time. Unless it is fairly new.

I would suggest creating a test machine and testing it out.

Reply
0 Kudos
kverneland
Contributor
Contributor

If i use the masking above i still get this -> CPU incompatible. problem detected at CPUID level 0x80000001 register 'edx' Smiley Sad

Reply
0 Kudos
mstahl75
Virtuoso
Virtuoso

Maybe change

edx ---0 -


-


-


-


-


-


-


to

edx 0000 -


-


-


-


-


-


-


?

Reply
0 Kudos
VirtualKenneth
Virtuoso
Virtuoso

kverneland, have you every get this to work? i'm in the exact same situation at the moment and need to know if this will work.

Thanks.

Reply
0 Kudos
VirtualKenneth
Virtuoso
Virtuoso

No one who did this before?

I can't test this masking thing cause the systems aren't onsite.

Reply
0 Kudos
badcrc_32
Contributor
Contributor

I got the same deal going on...Vmotion was fine before; however after the vc upgrade it failed....Im thinking of going all dual core and replacing the processors sounds like a great idea!!!

Reply
0 Kudos