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I'm pretty much a newbie when it comes to the Xen Hypervisor, either way I installed it on a dedicated server, I just removed OpenVZ since it was annoying me. So, I followed however I got kind of stuck in the grub part and it wouldn't properly boot into the Xen kernel since xend wouldn't start properly, so I followed and used it's grub configuration and slightly modified it, I have a local copy of my grub that I used.

title CentOS with Xen (
    root (hd0,0)
    kernel /vmlinuz- dom0_mem=1024M cpufreq=xen dom0_max_vcpus=1 dom0_vcpus_pin ro root=/dev/mapper/vg-root rd_DM_UUID=nvidia_jbbdgddd rd_LVM_LV=vg/root rd_LVM_LV=vg/swap rd_NO_LUKS rd_NO_MD LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=auto rhgb quiet
    initrd /initramfs-

It booted fine, seemingly so, until I checked a few bits and pieces out in "xm info".

total_memory           : 2046
free_memory            : 516

So then I logically went to check "free"'s output (in MB).

          total       used       free     shared    buffers     cached
Mem:          1505        769        736          0         31        384
-/+ buffers/cache:        353       1152
Swap:         4031          0       4031

However I have 2GB of physical membory and only 1505MB is displaying.

Furthermore I'm not able to find the grub bootloader config anymore to boot into the normal kernel so I'm sort of stuck for ideas on what to do, my server provider charges $25 for a reinstall so.. yeah.

Any ideas, is this actually a problem or my lack of knowledge?

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You have 1505MB allocated to this Linux instance now and 516MB free in the hypervisor. That totals to 2021MB. The hypervisor itself is using around 25MB. That's close enough to 2GB in my book.

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Thanks, sounds right. So I should be increasing the hypervisor's allocation and reducing the Linux instance's allocation. Any idea on how I would go around doing that since my grub file is no where to be seen.. – notFound Apr 15 '12 at 13:23

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