| |
|
 |
|
 |
|
|
|
| |
|
|
xen-users
Re: [Xen-users] 32bit paravirt guests on large memory machines
Hi
No-one any comment/experience/knowledge on the issue below? Should I be
asking on xen-devel?
Thanks,
Kevin
Hi Xen-Users
My question relates to this comment in the xend config file on my SLES 11 SP1
installation
--> snip
# 32-bit paravirtual domains can only consume physical
# memory below 168GB. On systems with memory beyond that address,
# they'll be confined to memory below 128GB.
# Using total_available_memory (in GB) to specify the amount of memory
reserved
# in the memory pool exclusively for 32-bit paravirtual domains.
# Additionally you should use dom0_mem = <-Value> as a parameter in
# xen kernel to reserve the memory for 32-bit paravirtual domains, default
# is "0" (0GB).
(total_available_memory 0)
--> snip
I have a system with 256 GB of RAM (and many cores). Our intention had been
to run a large number of 32 bit paravirtual guests, with each guest having 4
or 8 cores and 16 GB RAM assigned, on that system. The restrictions
indicated above pose a problem.
1) Can someone clarify if this restriction is a Xen restriction, which is
possible or likely to be lifted/relaxed at some future date? I note that Xen
on SLES is based on xen-4.0.0. Or is it a (hardware/addressing/...)
limitation that simply cannot be "fixed"?
2) Have I interpreted correctly, in that with Xen 4 I will not be able to use
any memory above 128GB for any 32 bit para-virtualised guests, independent of
the kernel/config/release of the guest itself? Experiment has led me to
suppose my interpretation is correct, but I feel worth double checking?
3) Is the restriction also independent of the Xen hypervisor used, e.g. it
does not matter if the hypervisor is 32 bit or 64 bit?
Thanks,
Kevin
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
|
|
|
| |
|
Home