--- On Sun, 1/3/10, Michael Tüxen <michael.tue...@lurchi.franken.de> wrote:
> From: Michael Tüxen <michael.tue...@lurchi.franken.de> > Subject: Re: igb interrupt moderation > To: "Barney Cordoba" <barney_cord...@yahoo.com> > Cc: "Mike Tancsa" <m...@sentex.net>, freebsd-net@freebsd.org > Date: Sunday, January 3, 2010, 12:14 PM > On Jan 3, 2010, at 6:00 PM, Barney > Cordoba wrote: > > > > > > > --- On Sun, 1/3/10, Michael Tüxen <michael.tue...@lurchi.franken.de> > wrote: > > > >> From: Michael Tüxen <michael.tue...@lurchi.franken.de> > >> Subject: Re: igb interrupt moderation > >> To: "Mike Tancsa" <m...@sentex.net> > >> Cc: "Barney Cordoba" <barney_cord...@yahoo.com>, > jfvo...@gmail.com, > freebsd-net@freebsd.org > >> Date: Sunday, January 3, 2010, 11:38 AM > >> On Jan 3, 2010, at 5:23 PM, Mike > >> Tancsa wrote: > >> > >>> At 11:13 AM 1/3/2010, Michael Tüxen wrote: > >>>>> > >>>>> Just a separate datapoint about this > driver, > >> unless I apply > >>>>> > >>>>> http://people.freebsd.org/~yongari/igb/igb.buf.patch6 > >>>>> > >>>>> the driver is not really usable for me > in > >> RELENG_8 on the dual port version of the card > >>>> Could you elaborate on what you mean by > "not > >> really usable"? > >>> > >>> > >>> Hi, > >>> Some > link state issues > >> (getting confused about what port is up), problems > at high > >> packet rates. I dont have this card in > production, but > >> in my test environment it was much more stable on > RELENG_8 > >> with the above patch in that I was not able to > wedge the > >> box. pps rates were pretty ok on a low end > i7 as > >> well. > >> Thanks for the information. I'll give it a try. I > have a > >> problem when I flood > >> a system with SCTP INITs. The system under attack > becomes > >> completely unresponsive > >> on the console. However, it continues to send > INIT-ACKs > >> back. After the last > >> commit from Jack it recovers after the attack. Not > yet sure > >> what is going on. > >> Using the em driver does not have the problem. > However, > >> when using the em > >> driver only one core is fully used, when using the > igb > >> driver both cores are fully > >> used. Unfortunately I do not have a more than dual > core > >> machine available for > >> this testing... > > > > Try em and lower the interrupt moderation to something > like 500 (about > > 100 packets per int is good). The latency isn't going > to be noticable and > > you'll see your cpu burden reduced quite a bit. > I'll try. Thanks. > > > > Are you using a single NIC on a server, or do you have > a firewall or > > bridge? > The system is a sender/receiver for SCTP. I'm interested in > the 82576 > since it provides checksum offloading for it. I use one or > two ports > for simultaneous data transfer. The cards using the em > driver do > not support this feature. So I'm trying to verify that the > performance > goes up when using hardware checksum. But under attack, > this is currently > not the case... > > > > Barney Are you using just 1 queue? Just because you're using both cpus doesn't mean its efficient. The 8257x has separate interrupts for transmit and receive, so 1 queue will be a closer match to the em driver so you can gauge if the offload is effective. I don't know how far jack has gotten in addressing the lock contention issue in igb. Obviously, try all scenarios. What seems obvious rarely plays out in practice. Barney _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
