From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jakub Kicinski <kubakici@wp.pl>
Subject: Re: [RFC PATCH] net: limit maximum number of packets to mark with
 xmit_more
Date: Fri, 25 Aug 2017 15:34:18 -0400
Message-ID: <20170825153418.53864810@cakuba>
References: <20170825152449.29790-1-jacob.e.keller@intel.com>
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To: Jacob Keller <jacob.e.keller@intel.com>
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On Fri, 25 Aug 2017 08:24:49 -0700, Jacob Keller wrote:
> Under some circumstances, such as with many stacked devices, it is
> possible that dev_hard_start_xmit will bundle many packets together, and
> mark them all with xmit_more.

Excuse my ignorance but what are those stacked devices?  Could they
perhaps be fixed somehow?  My intuition was that long xmit_more
sequences can only happen if NIC and/or BQL are back pressuring, and
therefore we shouldn't be seeing a long xmit_more "train" arriving at
an empty device ring...