Re: Major network performance regression in 3.7

Eric Dumazet
2013-01-06T19:39:36Z

On Sun, 2013-01-06 at 20:34 +0100, Willy Tarreau wrote:

> OK it works like a charm here now ! I can't break it anymore, so it
> looks like you finally got it !
>
> I noticed that the data rate was higher when the loopback's MTU
> is exactly a multiple of 4096 (making the 64k choice optimal)
> while I would have assumed that in order to efficiently splice
> TCP segments, we'd need to have some space for IP/TCP headers
> and n*4k for the payload.
>
> I also got the transfer freezes again a few times when starting
> tcpdump on the server, but this is not 100% reproducible I'm afraid.
> So I'll bring this back when I manage to get some analysable pattern.
>
> The spliced transfer through all the chain haproxy works fine again
> at 10gig with your fix. The issue is closed for me. Feel free to add
> my Tested-By if you want.
>

Good to know !

What is the max speed you get now ?