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From: "Lu, Wenzhuo" <wenzhuo.lu@intel.com>
To: Stephen Hemminger <shemming@brocade.com>
Thread-Topic: igb PMD should set the default tx wthresh correctly.
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Date: Fri, 17 Jul 2015 00:52:09 +0000
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Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] igb PMD should set the default tx wthresh correctly.
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Hi Stephen,
I don't think there's a conflict. The message just reminder us that we can =
adjust the values to achieve better performance.
I saw ixgbe and i40e also use 0 as the same default value. To my opinion, i=
t's good to keep the same behavior.
Thanks.

> -----Original Message-----
> From: Stephen Hemminger [mailto:shemming@brocade.com]
> Sent: Friday, July 17, 2015 1:17 AM
> To: Lu, Wenzhuo
> Cc: dev@dpdk.org
> Subject: igb PMD should set the default tx wthresh correctly.
>=20
> Why doesn't igb driver set the wthresh it wants as default?
>=20
> I see:
> 	PMD: eth_igb_tx_queue_setup(): To improve 1G driver performance,
> consider setting the TX WTHRESH value to 4, 8, or 16.
>=20
> But the default tx_conf has wthresh of 0.
>=20
> 	#define IGB_DEFAULT_TX_WTHRESH      0
>=20
>=20
> Either message should be removed or default TX wthresh should change.