RE: [PATCH] ethtool: add one ethtool option to set relax ordering mode

-----Original Message-----
From: Stephen Hemminger [mailto:stephen@networkplumber.org]
Sent: Thursday, December 22, 2016 9:28 AM
To: maowenan
Cc: netdev@vger.kernel.org; jeffrey.t.kirsher@intel.com
Subject: Re: [PATCH] ethtool: add one ethtool option to set relax ordering mode

On Thu, 8 Dec 2016 14:51:38 +0800
Mao Wenan [off-list ref] wrote:

quoted

This patch provides one way to set/unset IXGBE NIC TX and RX relax
ordering mode, which can be set by ethtool.
Relax ordering is one mode of 82599 NIC, to enable this mode can
enhance the performance for some cpu architecure.

Then it should be done by CPU architecture specific quirks (preferably in PCI
layer) so that all users get the option without having to do manual intervention.

quoted

example:
ethtool -s enp1s0f0 relaxorder off
ethtool -s enp1s0f0 relaxorder on

Doing it via ethtool is a developer API (for testing) not something that makes
sense in production.

This feature is not mandatory for all users, acturally relax ordering default configuration of 82599 is 'disable',
So this patch gives one way to enable relax ordering to be selected in some performance condition.