[Virtio-fs] Achieving parallelism in virtiofsd

[Peng Tao]

On Fri, Jul 5, 2019 at 4:04 PM Stefan Hajnoczi <stefanha at redhat.com> wrote:
>
> On Fri, Jul 05, 2019 at 12:43:16PM +0800, piaojun wrote:
> > From your description, virtiofsd does the same work as SPDK, and I
> > wonder if we could adapt it to SPDK-vhost-fs which is widely used.
>
> I don't see 9P code in spdk.git/master.  How does the guest access
> SPDK's vhost-fs device and where is the code?
>
> A quick look at blobfs suggests additional work is needed to introduce
> the concept of inodes instead of performing path name traversal on most
> operations.  This also changes the semantics of the file system since
> POSIX files can still be accessed after they are unlinked or renamed.
>
> In theory SPDK can implement the vhost-user-fs device interface and
> replace virtiofsd but SPDK needs a POSIX file system implementation
> first.
Intel has presented virtiofsd+blobfs+SPDK in KubeCon Shanghai last
month. As you have spotted, the main problem is on blobfs side and
virtio-fs DAX sharing is not working because of blobfs limitation.

Cheers,
Tao
-- 
Into something rich and strange.