>
> You want to have CONFIG_NET_HW_FLOWCONTROL enabled. If you don't the
> kernel gets _alot_ of interrupts from the NIC and dosn't have
> any cycles
> left to do anything. So you want to turn this on!
>
> > At the NordU/USENIX conference in Stockholm (this february) I
> > saw a nice presentation on the flow control code in the Linux
> > networking code and how it improved networking performance.
> > I'm pretty convinced that flow control _should_ be saving your
> > system in this case.
>
> That was probably Jamal Hadi and Robert Olsson. They have
> been optimizing
> the tulip driver. These optimizations havn't been integrated with the
> "vanilla" driver yet, but I hope the can integrate it soon.
>
> They have one version that is very optimized and then they have one
> version that have even more optimizations, ie. it uses polling at high
> interruptload.
>
> you will find these drivers here:
> ftp://robur.slu.se/pub/Linux/net-development/
> The latest versions are:
> tulip-ss010111.tar.gz
> and
> tulip-ss010116-poll.tar.gz
>
> > OTOH, if they _are_ enabled, the networking people seem to have
> > a new item for their TODO list. ;)
>
> Yup.
>
> You can take a look here too:
>
> http://robur.slu.se/Linux/net-development/jamal/FF-html/
>
> This is the presentation they gave at OLS (IIRC)
>
> And this is the final result:
>
> http://robur.slu.se/Linux/net-development/jamal/FF-html/img26.htm
>
> As you can see the throughput is a _lot_ higher with this driver.
>
> One final note: The makefile in at least
> tulip-ss010111.tar.gz is in the
> old format (not the new as 2.4.0-testX introduced), but you
> can copy the
> makefile from the "vanilla" driver and It'lll work like a charm.
>
> Please redo your tests with this driver and report the
> results to me and
> this list. I really want to know how it compares against FreeBSD.
>
> /Martin
Thanks! I'll try that out. How can I tell if the driver supports
CONFIG_NET_HW_FLOWCONTROL? I'm not sure, but I think the cards are
tulip-based, can I then use Robert & Jamal's optimised drivers?
It'll probably take some time before I can do further testing. (My employer
thinks I've spent too much time on it already...).
FYI, Linux had _much_ better delay variation characteristics than FreeBSD.
Typically no packet was delayed more than 100usec, whereas FreeBSD had some
packets delayed about 2-3 msec.
/Mårten
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Fri Mar 23 2001 - 21:00:08 EST