From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Subject: Re: SQ overflow seen running isert traffic
Date: Tue, 18 Oct 2016 10:13:13 -0600
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To: Steve Wise <swise@opengridcomputing.com>
Cc: 'Sagi Grimberg' <sagi@grimberg.me>, 'Potnuri Bharat Teja' <bharat@chelsio.com>, target-devel@vger.kernel.org, nab@linux-iscsi.org, linux-rdma@vger.kernel.org
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On Tue, Oct 18, 2016 at 09:34:33AM -0500, Steve Wise wrote:

> 1) we believe the iSER + RW API correctly sizes the SQ, yet we're seeing SQ
> overflows.  So the SQ sizing needs more investigation.

NFS had this sort of problem - in that case it was because the code
was assuming that a RQ completion implied SQ space - that is not
legal, only direct completions from SQ WCs can guide available space
in the SQ..

Jason