Subject: Re: Bonding gigabit and fast?

From: "Tvrtko A. Ursulin" <[email-masked]>
Date: Wed, 17 Dec 2008 07:51:55 +0000

On Wednesday 17 December 2008 02:53:10 Trent Piepho wrote:
> If the transmitter is sending out packets round-robin on two links, it's
> sending the packets like this:
>
> Link A:  1   3   5   7
> Link B:    2   4   6   8
>
> If the cards return two packets per interrupt, the receiver gets them like
> this:
>
> Link A:  1 3     5 7
> Link B:      2 4     6 8
>
> Well, the Linux kernel does not like getting the packets in the order (1 3
> 2 4 5 7 6 8).  It likes to get the packets in the correct order.  And so
> performance suffers.  At the time, it suffered greatly.  Maybe it's better
> or worse now?

I don't know, but to clarify I was never aiming to get higher than gigabit 
speed, even on the receiver side there is only single gigabit link. From the 
bonding HOWTO I understood that in this configuration packets my actually 
arrive in order.

Point of my experiment was to see if I can work around very slow gigabit 
speeds (<10Mb/s) I was getting while serving data out with Samba. So I was 
hoping to get 20 Mb/s sustained with this slow gigabit and normally fast fast 
ethernet. But yeah, bonding seemed to cause aggregated speed to be somewhat 
less than when each were alone.

Tvrtko