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Date:   Thu, 13 May 2021 16:15:51 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Cc:     Leon Romanovsky <leon@kernel.org>,
        "Marciniszyn, Mike" <mike.marciniszyn@cornelisnetworks.com>,
        Doug Ledford <dledford@redhat.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>
Subject: Re: [PATCH rdma-next] RDMA/rdmavt: Decouple QP and SGE lists
 allocations
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On Thu, May 13, 2021 at 03:03:43PM -0400, Dennis Dalessandro wrote:
> On 5/12/21 8:50 AM, Leon Romanovsky wrote:
> > On Wed, May 12, 2021 at 12:25:15PM +0000, Marciniszyn, Mike wrote:
> > > > > Thanks Leon, we'll get this put through our testing.
> > > > 
> > > > Thanks a lot.
> > > > 
> > > > > 
> > > 
> > > The patch as is passed all our functional testing.
> > 
> > Thanks Mike,
> > 
> > Can I ask you to perform a performance comparison between this patch and
> > the following?
> 
> We have years of performance data with the code the way it is. Please
> maintain the original functionality of the code when moving things into the
> core unless there is a compelling reason to change. That is not the case
> here.

Well, making the core do node allocations for metadata on every driver
is a pretty big thing to ask for with no data.

Jason