[dpdk-dev] The limitation of VHOST_MEMORY_MAX_NREGIONS in virtio-user with vhost-user backend

[Yuanhan Liu]

On Tue, Dec 05, 2017 at 06:58:53AM +0000, Wang, Wei 5. (NSB - CN/Hangzhou) wrote:
> 
> 
> Hi, all
> 
> In DPDK document, it it described that Virtio in containers Cannot work when there are more than VHOST_MEMORY_MAX_NREGIONS(8) hugepages. In another word, do not use 2MB hugepage so far. Do you know the reason of this limitation?

It comes from the vhost-user spec.

> In my envirionment, the pdpe1gb is not set in cpu flag, so hugepage can't be set to 1GB size. The hugepage number shall be more than 8
> 
> 
> So is there any solution or workaround to fix this limitation? Or change dpdk code to fix this limitation?
> 

AFAIK, there are no workarounds. And I think the DPDK EAL memory code need be
refactored a bit to fix this limitation. Unforunately, seems there are no work
on that recently.

	--yliu