Hey all, just compiled xen 3.4.2 and linux 2.6.31.12. I followed the instructions on the Xen wiki to get the install running. my issue here is that in my grub memnu config i set dom0_mem=512M when i login to the dom0 and i do a free -m i get that the system only has 432 under the total section. booting into the stock debian kernel 2.6.26-2-amd64 kernel gives me 8192 free memory for i did not limit that. when i run xm info |grep memory under the xen kernel I get the following. total_memory : 8191 free_memory : 7578 node_to_memory : node0:7578 the server only has 8gb of memory installed which is confirmed via the system bios. is there anyway to figure out what is going on here? _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Thu, Mar 11, 2010 at 07:04:49PM -0500, Robbie Garertt wrote:> Hey all, > > just compiled xen 3.4.2 and linux 2.6.31.12. I followed the instructions > on the Xen wiki to get the install running. > > my issue here is that in my grub memnu config i set dom0_mem=512M > when i login to the dom0 and i do a free -m i get that the system only has > 432 under the total section. >Try reading "xm dmesg", or capturing that to a file at boot time using a serial console.> booting into the stock debian kernel 2.6.26-2-amd64 kernel gives me 8192 > free memory for i did not limit that. > when i run xm info |grep memory under the xen kernel I get the following. > total_memory : 8191 > free_memory : 7578 > node_to_memory : node0:7578 >What does "xm list" show about dom0 memory? 8GB is 8192 MB, so 8191 MB total memory sounds correct. 8191 - 7578 = 613 MB. If dom0 has 432 MB, then there''s 181 MB used for something else. Xen hypervisor (or was it dom0 kernel?) allocates some memory as a DMA reserve, and there''s some overhead per every MB of memory, and per every vcpu. -- Pasi> the server only has 8gb of memory installed which is confirmed via the > system bios. > > is there anyway to figure out what is going on here? > >> _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Thanks for this follow-up. we are now seeing 511 as total memory in the xen dom0 kernel. when I do xm info |grep memory it shows a total of 8191. my new issue here is something with xen balloon driver. In my vm I have configured memory = ''512'' but according to the xen-debug.log and xend.log it shows the balloon drivers requesting other totals then 512. Some times more, some times less. did I miss a configure option when I built the kernel? ________________________________ From: Pasi Kärkkäinen [mailto:pasik@iki.fi] Sent: Fri 3/12/2010 4:33 AM To: Robbie Garertt Cc: xen-users@lists.xensource.com Subject: Re: [Xen-users] dom0 incorrect mem size On Thu, Mar 11, 2010 at 07:04:49PM -0500, Robbie Garertt wrote:> Hey all, > > just compiled xen 3.4.2 and linux 2.6.31.12. I followed the instructions > on the Xen wiki to get the install running. > > my issue here is that in my grub memnu config i set dom0_mem=512M > when i login to the dom0 and i do a free -m i get that the system only has > 432 under the total section. >Try reading "xm dmesg", or capturing that to a file at boot time using a serial console.> booting into the stock debian kernel 2.6.26-2-amd64 kernel gives me 8192 > free memory for i did not limit that. > when i run xm info |grep memory under the xen kernel I get the following. > total_memory : 8191 > free_memory : 7578 > node_to_memory : node0:7578 >What does "xm list" show about dom0 memory? 8GB is 8192 MB, so 8191 MB total memory sounds correct. 8191 - 7578 = 613 MB. If dom0 has 432 MB, then there''s 181 MB used for something else. Xen hypervisor (or was it dom0 kernel?) allocates some memory as a DMA reserve, and there''s some overhead per every MB of memory, and per every vcpu. -- Pasi> the server only has 8gb of memory installed which is confirmed via the > system bios. > > is there anyway to figure out what is going on here? > >> _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users