That means, both low GM and high GM are the size that how much GM size can
VM use on real graphic aperture size?
And DVMT won't work if guest OS is Windows 7, it only works on Windows XP
guest and KVMGT host?
I'm thinking about that because my server (SYS-5038A-iL) can only set
aperture size to 1GB.
Even it can set to 4GB, but it reboot automatically when trying to boot
into Ubuntu when I try set it to 2GB and 4GB.
2016-04-25 9:50 GMT+08:00 He, Min <min.he(a)intel.com>:
With higher resolution, both low and high GM will occupy more. But
low GM space is more limited, it will has more impact to low GM space.
Also maximum DVMT, from what I know, is only for older OSes like Windows
XP. It’s not related to vgt_high_gm_sz.
*From:* Eddie Yen [mailto:email@example.com]
*Sent:* Monday, April 25, 2016 9:23 AM
*To:* He, Min <min.he(a)intel.com>
*Cc:* slawek <slawek8(a)gmail.com>; igvt-g(a)lists.01.org
*Subject:* Re: [iGVT-g] gm size
Sorry, wrong type.
"And the mzximum DVMT usage is depends on -vmg_high_gm_sz ?"
"And the maximum DVMT usage is depends on -vgt_high_gm_sz ?"
2016-04-25 9:21 GMT+08:00 Eddie Yen <missile0407(a)gmail.com>:
So, with higher resolution of VM display, which gfx memory will occupy
more? Is DVMT works at this part?
And the mzximum DVMT usage is depends on -vmg_high_gm_sz ?
2016-04-25 8:58 GMT+08:00 He, Min <min.he(a)intel.com>:
The message " fail to allocate space from whole GM space" is kind of
misleading: actually there's no enough space from the low GM space.
You can take a look at i915_gem.c. In function i915_gem_object_bind_to_vm,
it uses obj->map_and_fenceable to judge low/whole GM, but at that time,
obj->map_and_fenceable is not initialized. So it will always output "whole
For your issue, based on our experience, if your screen resolution is too
high, sometimes i915 will report such no GM space message, since Xserver,
compositor will occupy more gfx memory when resolution is higher.
> -----Original Message-----
> From: iGVT-g [mailto:firstname.lastname@example.org] On Behalf Of slawek
> Sent: Monday, April 25, 2016 6:38 AM
> To: igvt-g(a)lists.01.org
> Subject: Re: [iGVT-g] gm size
> On Sun, Apr 24, 2016 at 4:43 PM, Zhang, Pei <pei.zhang(a)intel.com> wrote:
> > Your total aperture size is 256M, and there are 128M already used by
> > So for the domU, there are maximum 128M available. This is why you
> > the resource allocation failure log when you try to set 192M. And for
> > vgt_hi_gm_sz, please use 384 or a higher value.
> > For the other issue you referred, that you see log
> > “[drm:i915_gem_object_do_pin [i915]] *ERROR* fail to allocate space
> > whole GM space, size: 8”. Did you do anything special when/before you
> > this log? And could you attach a full log file for analyze? Thanks.
> I have isolated this issue.
> No VM is running at all. Testing just after boot.
> About 23:59:07 - I have connected external monitors via dsub and dp
> port (but output is disabled).
> About 23:59:31 - I have enabled output on both monitors using xrandr.
> at that moment I got fail to allocate space from whole GM space, size:
> a little later my X server was frozen.
> I couldn't even switch to text console - I need to power off the system.
> I don't have any problems with this configuration using non-vgt kernel.
> full kernel log:
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