From mboxrd@z Thu Jan  1 00:00:00 1970
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [PATCH 04/10] xen/blkfront: separate ring
 information to an new struct
Date: Wed, 4 Mar 2015 16:21:40 -0500
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> > David assertion that better performance and scalbility can be gained
> > with grant table locking and TLB flush avoidance is interesting - as
> > 1). The grant locking is going in Xen 4.6 but not earlier - so when running
> >     on older hypervisors this gives an performance benefit.
> > 
> > 2). I have not seen any prototype TLB flush avoidance code so not know
> >     when that would be available.
> > 
> > Perhaps a better choice is to do the removal of the persistence support
> > when the changes in Xen hypervisor are known?
> > 
> 
> With patch: [PATCH v5 0/2] gnttab: Improve scaleability, I can get
> nearly the same performance as without persistence support.
> 
> But I'm not sure about the benchmark described here:
> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/drivers/block/xen-blkfront.c?id=0a8704a51f386cab7394e38ff1d66eef924d8ab8

Meaning you weren't able to do the same test?

> 
> -- 
> Regards,
> -Bob