From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Ananyev, Konstantin" Subject: Re: [PATCH] ixgbe: do not include CRC in Tx byte count Date: Tue, 24 Mar 2015 23:54:18 +0000 Message-ID: <2601191342CEEE43887BDE71AB977258214074F6@irsmsx105.ger.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Cc: "dev-VfR2kkLFssw@public.gmane.org" , Stephen Hemminger To: Stephen Hemminger Return-path: Content-Language: en-US List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces-VfR2kkLFssw@public.gmane.org Sender: "dev" Hi Stephen, > -----Original Message----- > From: Stephen Hemminger [mailto:stephen-OTpzqLSitTUnbdJkjeBofR2eb7JE58TQ@public.gmane.org] > Sent: Tuesday, March 24, 2015 3:55 PM > To: Ananyev, Konstantin > Cc: dev-VfR2kkLFssw@public.gmane.org; Stephen Hemminger > Subject: Re: [dpdk-dev] [PATCH] ixgbe: do not include CRC in Tx byte coun= t >=20 > On Mon, 23 Mar 2015 16:45:44 +0000 > "Ananyev, Konstantin" wrote: >=20 > > > > > > > -----Original Message----- > > > From: dev [mailto:dev-bounces-VfR2kkLFssw@public.gmane.org] On Behalf Of stephen@networkp= lumber.org > > > Sent: Friday, January 23, 2015 6:24 AM > > > To: dev-VfR2kkLFssw@public.gmane.org > > > Cc: Stephen Hemminger > > > Subject: [dpdk-dev] [PATCH] ixgbe: do not include CRC in Tx byte coun= t > > > > > > From: Stephen Hemminger > > > > > > The ixgbe driver was including CRC in the transmit packet byte > > > count, but not for packets received. > > > This was notice when forwarding and > > > the number of bytes received was greater than the number of bytes tra= nsmitted > > > for the same number of packets. Make the driver behave like other > > > virtual devices and not include CRC in byte count. Use the same queue > > > counters already computed and used for Rx. > > > > About RX side stats - as I remember it depends to what value hw_stip_cr= c is set at configure(). > > If hw_stip_crc=3D=3D1, then, yes CRC bytes are not included into QBRC = value. > > I If hw_stip_crc=3D=3D0, then CRC bytes are included into QBRC. >=20 > That is an additional bug! > * CRC should never be included in the byte count. > This is not how Linux or other drivers report byte count. I don't have any strong opinion here... For me any method (with or without CRC) of counting bytes are ok, as long a= s this method is identical across all PMDs we support. Which makes we wonder, what approach other PMDs use?=20 >=20 > * the byte count must be symmetrical Rx =3D=3D Tx >=20 > The Brocade router always set strip_crc to 1. So did not see the addition= al bug > of CRC being included in byte count. Are you going to submit v2, to make Rx=3D=3DTx for both cases? Konstantin >=20 >=20