K220Q Video Ram - XenServer 6.5

NVIDIA Virtual GPU Forums Virtual GPU XenDesktop
#1

I just noticed an oddity with our K2 cards running on XenServer 6.5 The amount of memory for the vGpu profiles appears off.

For example the K220Q profile should have 512mb of video ram as detailed here:

http://blogs.citrix.com/2014/03/31/new-nvidia-vgpu-types-for-citrix-xendesktop-now-supports-the-nvidia-k120q-and-k220q-are-these-the-goldilocks-vgpu/

On the XenServer host we are only seeing 416MB of video ram. Currently our environment contains two HP DL 380 G9s with 4 K2’s. Each host is on 6.5 and running the latest driver 340.57.

This inconsistency has thrown a wrench in the sizing of our environment. Can the amount of video memory for these profiles be adjusted via the CLI??

#2

Hello.

NVidia newer hypervisor (~second half 2014) drivers lower ram assignments (probably Nvidia has some undocumented issues with full-ram assignments).

#  grep framebufferlength /usr/share/nvidia/vgx/*
/usr/share/nvidia/vgx/grid_k100.conf:plugin0.framebufferlength 0x10000000
/usr/share/nvidia/vgx/grid_k120q.conf:plugin0.framebufferlength 0x1A000000
/usr/share/nvidia/vgx/grid_k140q.conf:plugin0.framebufferlength 0x38000000
/usr/share/nvidia/vgx/grid_k160q.conf:plugin0.framebufferlength 0x74000000
/usr/share/nvidia/vgx/grid_k180q.conf:plugin0.framebufferlength 0xEC000000
/usr/share/nvidia/vgx/grid_k200.conf:plugin0.framebufferlength 0x10000000
/usr/share/nvidia/vgx/grid_k220q.conf:plugin0.framebufferlength 0x1A000000
/usr/share/nvidia/vgx/grid_k240q.conf:plugin0.framebufferlength 0x38000000
/usr/share/nvidia/vgx/grid_k260q.conf:plugin0.framebufferlength 0x74000000
/usr/share/nvidia/vgx/grid_k280q.conf:plugin0.framebufferlength 0xEC000000

K220Q == 0x1A000000 == 436207616 == 416 MiB

Probably you can set "framebufferlength" (search driver "Release notes" for similar "frame_rate_limiter" parameter setting) but the result seems to be unsupported or driver can crash.

M.C>

#3

What are you seeing inside the VM if you look in Nvidia Control Panel / System Information

What value is given for dedicated graphics memory?

Don’t forget that vGPU Manager utilises a portion of the GPU’s framebuffer for pagetables to ensure segregation of the vGPU sessions and this is being accounted for in the value presented in XenServer’s CLI.

#4

The video ram sizes are now reported "correctly".
Nvidia added compensation parameter "reserved_fb" to hide virtualization lost.

K220Q == 0x1A000000 + 0x6000000 = 0x20000000 == 536870912 == 512 MiB

#  egrep 'framebufferlength|reserved_fb' /usr/share/nvidia/vgx/*
/usr/share/nvidia/vgx/grid_k100.conf:plugin0.framebufferlength 0x10000000
/usr/share/nvidia/vgx/grid_k120q.conf:plugin0.framebufferlength 0x1A000000
/usr/share/nvidia/vgx/grid_k120q.conf:plugin0.reserved_fb 0x6000000
/usr/share/nvidia/vgx/grid_k140q.conf:plugin0.framebufferlength 0x38000000
/usr/share/nvidia/vgx/grid_k140q.conf:plugin0.reserved_fb 0x8000000
/usr/share/nvidia/vgx/grid_k160q.conf:plugin0.framebufferlength 0x74000000
/usr/share/nvidia/vgx/grid_k160q.conf:plugin0.reserved_fb 0xC000000
/usr/share/nvidia/vgx/grid_k180q.conf:plugin0.framebufferlength 0xEC000000
/usr/share/nvidia/vgx/grid_k180q.conf:plugin0.reserved_fb 0x14000000
/usr/share/nvidia/vgx/grid_k200.conf:plugin0.framebufferlength 0x10000000
/usr/share/nvidia/vgx/grid_k220q.conf:plugin0.framebufferlength 0x1A000000
/usr/share/nvidia/vgx/grid_k220q.conf:plugin0.reserved_fb 0x6000000
/usr/share/nvidia/vgx/grid_k240q.conf:plugin0.framebufferlength 0x38000000
/usr/share/nvidia/vgx/grid_k240q.conf:plugin0.reserved_fb 0x8000000
/usr/share/nvidia/vgx/grid_k260q.conf:plugin0.framebufferlength 0x74000000
/usr/share/nvidia/vgx/grid_k260q.conf:plugin0.reserved_fb 0xC000000
/usr/share/nvidia/vgx/grid_k280q.conf:plugin0.framebufferlength 0xEC000000
/usr/share/nvidia/vgx/grid_k280q.conf:plugin0.reserved_fb 0x14000000
/usr/share/nvidia/vgx/grid_m60-0b.conf:plugin0.framebufferlength 0x1A000000
/usr/share/nvidia/vgx/grid_m60-0b.conf:plugin0.reserved_fb 0x6000000
/usr/share/nvidia/vgx/grid_m60-0q.conf:plugin0.framebufferlength 0x1A000000
/usr/share/nvidia/vgx/grid_m60-0q.conf:plugin0.reserved_fb 0x6000000
/usr/share/nvidia/vgx/grid_m60-1b.conf:plugin0.framebufferlength 0x38000000
/usr/share/nvidia/vgx/grid_m60-1b.conf:plugin0.reserved_fb 0x8000000
/usr/share/nvidia/vgx/grid_m60-1q.conf:plugin0.framebufferlength 0x38000000
/usr/share/nvidia/vgx/grid_m60-1q.conf:plugin0.reserved_fb 0x8000000
/usr/share/nvidia/vgx/grid_m60-2b.conf:plugin0.framebufferlength 0x74000000
/usr/share/nvidia/vgx/grid_m60-2b.conf:plugin0.reserved_fb 0xC000000
/usr/share/nvidia/vgx/grid_m60-2q.conf:plugin0.framebufferlength 0x74000000
/usr/share/nvidia/vgx/grid_m60-2q.conf:plugin0.reserved_fb 0xC000000
/usr/share/nvidia/vgx/grid_m60-4q.conf:plugin0.framebufferlength 0xEC000000
/usr/share/nvidia/vgx/grid_m60-4q.conf:plugin0.reserved_fb 0x14000000
/usr/share/nvidia/vgx/grid_m60-8q.conf:plugin0.framebufferlength 0x1DC000000
/usr/share/nvidia/vgx/grid_m60-8q.conf:plugin0.reserved_fb 0x24000000
/usr/share/nvidia/vgx/grid_m6-0b.conf:plugin0.framebufferlength 0x1A000000
/usr/share/nvidia/vgx/grid_m6-0b.conf:plugin0.reserved_fb 0x6000000
/usr/share/nvidia/vgx/grid_m6-0q.conf:plugin0.framebufferlength 0x1A000000
/usr/share/nvidia/vgx/grid_m6-0q.conf:plugin0.reserved_fb 0x6000000
/usr/share/nvidia/vgx/grid_m6-1b.conf:plugin0.framebufferlength 0x38000000
/usr/share/nvidia/vgx/grid_m6-1b.conf:plugin0.reserved_fb 0x8000000
/usr/share/nvidia/vgx/grid_m6-1q.conf:plugin0.framebufferlength 0x38000000
/usr/share/nvidia/vgx/grid_m6-1q.conf:plugin0.reserved_fb 0x8000000
/usr/share/nvidia/vgx/grid_m6-2b.conf:plugin0.framebufferlength 0x74000000
/usr/share/nvidia/vgx/grid_m6-2b.conf:plugin0.reserved_fb 0xC000000
/usr/share/nvidia/vgx/grid_m6-2q.conf:plugin0.framebufferlength 0x74000000
/usr/share/nvidia/vgx/grid_m6-2q.conf:plugin0.reserved_fb 0xC000000
/usr/share/nvidia/vgx/grid_m6-4q.conf:plugin0.framebufferlength 0xEC000000
/usr/share/nvidia/vgx/grid_m6-4q.conf:plugin0.reserved_fb 0x14000000
/usr/share/nvidia/vgx/grid_m6-8q.conf:plugin0.framebufferlength 0x1DC000000
/usr/share/nvidia/vgx/grid_m6-8q.conf:plugin0.reserved_fb 0x24000000