WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-users

Re: [Xen-users] xen on amd64 or intel

I first had also a mixed 64/32 bit setup with Xen 3.0.1: AMD64, 4GB
RAM, 2x250GB SATA Drives with a mix of software raid 1 and raid 0 (for
tmp and swap). The domU partitions were on LVM's, OS was debian sarge
amd64 + i386.

Most 32 and 64 bit domU's were working fine, but there was one problem
I could not get fixed (and why I finally changed everything to plain
32 bit using Xen 3.0.2 and debian etch-b2):

I could never connect to a DB2 instance running in a 32 bit domU
because it complained about not enough shared memory. I tried every
suggestion I could find, but finally found that the output if "ipcs
-l" did lack shared memory completely in 32 bit domU's whatever shared
memory setting I tried. So when the output is normally something as:

------ Shared Memory Limits --------
max number of segments = 4096
max seg size (kbytes) = 32768
max total shared memory (pages) = 2097152
min seg size (bytes) = 1

------ Semaphore Limits --------
max number of arrays = 128
max semaphores per array = 250
max semaphores system wide = 32000
max ops per semop call = 32
semaphore max value = 32767

------ Messages: Limits --------
max queues system wide = 16
max size of message (bytes) = 8192
default max size of queue (bytes) = 16384


In a 32 bit domU under 64 bit xen/dom0 it showed up as:


------ Shared Memory Limits --------

------ Semaphore Limits --------
max number of arrays = 128
max semaphores per array = 250
max semaphores system wide = 32000
max ops per semop call = 32
semaphore max value = 32767

------ Messages: Limits --------
max queues system wide = 16
max size of message (bytes) = 8192
default max size of queue (bytes) = 16384


Interestingly Oracle which also run in a 32 bit domU was not affected.
What does ipcs -l show in your 32 bit domU's?

Seneca



You wrote at Mittwoch, 12. April 2006 07:02:

HW> Am Mittwoch 12 April 2006 03:26 schrieb Edward Muller:
>> We have a quad core opteron system with 8GB of RAM, running Gentoo
>> (compiled for 64 bit kernel and userspace) and we run a mix of 32 bit and
>> 64 bit dom-U's.

HW> Something similar here: AMD64 with 4GB RAM running a 64-bit Gentoo Dom0, 
HW> running 30 DomUs, which are mixed 32-bit Debian/SuSE/FC4/CentOS and 64-bit 
HW> Gentoo, but all with a 64-bit kernel for the DomU. If you don't choose 
stupid 
HW> compiler-settings (beware of -Os, it creates broken code), it's running 
very, 
HW> very smoothly.

HW> --- Heiko.

HW> _______________________________________________
HW> Xen-users mailing list
HW> Xen-users@xxxxxxxxxxxxxxxxxxx
HW> http://lists.xensource.com/xen-users


_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users