Date: Mon, 27 Jul 2015 11:07:46 -0600
From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
To: Sagi Grimberg <sagig@dev.mellanox.co.il>
Cc: Steve Wise <swise@opengridcomputing.com>, dledford@redhat.com,
        infinipath@intel.com, sagig@mellanox.com, ogerlitz@mellanox.com,
        roid@mellanox.com, linux-rdma@vger.kernel.org, eli@mellanox.com,
        target-devel@vger.kernel.org, linux-nfs@vger.kernel.org,
        bfields@fieldses.org
Subject: Re: [PATCH V6 9/9] isert: Support iWARP transports using FRMRs
Message-ID: <20150727170746.GB18348@obsidianresearch.com>
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On Sun, Jul 26, 2015 at 01:23:12PM +0300, Sagi Grimberg wrote:

> Question though, wouldn't it be better to do a single RDMA_READ to say
> 4 registered keys rather than RDMA_READ_WITH_INV for each?

RDMA READ is limted to 1 sg in iWarp.

RDMA_READ_WITH_INV and 1 sg is really the only correct way to drive
iWarp.

Jason