On Tue, Jul 17, 2007 at 05:32:11AM -0400, thewird wrote:
I installed FC6 and FC7 and the limit exists on both even though FC7 was supposed to be using a 64bit hypervisor which supports 32bit guests (which isn't the case). After various linux installs (including CentOS) and different configs (even replacing the hypervisor with its 64bit counterpart) I wasn't able to get a system showing all 28GB of ram AND work with 32bit guests.
Out of desperation I bought "Virtualization with Xen" on Amazon for more insight. Although the book isn't too helpful since at least half of it if not more, is advertising the commercial XenSource (why would I buy an expensive Xen book if I wanted to use the newb commercial software?) I was able to figure out how to install the latest version of Xen 3.1 from source. I got it to boot perfectly and was expecting to see all of my 28GB of ram when I ran top but to my dismay it only showed 16GB once again...
What architecture did you compile with Xen 3.1 ? Because of the tricks Xen does on i386, even if you have PAE enabled you stil won't see more than 16 GB of RAM. I believe you need 64-bit HV to see all. You may or may not also need a 64-bit Dom0 - I don't know for sure since I'm not lucky enough to have more than 16 GB of RAM :-(
Can someone please help me and tell me what am I doing wrong. Or am I going about this the wrong way? Basically I want to see all of my 28GB of ram and run 32bit guests. I read everywhere this can be done but it never works. Thank you to anyone who can help me solve this. If money is the problem, please say so and that can be arranged.
We're working on a kernl update for Fedora that will hopefully make it possible to really run 32-bit guests on 64-bit hypervisor. If you did a compile from upstream Xen 3.1 kenrel this should be working for you already though.
Dan.