Updating our TCP and socket sysctl values...

[Bjoern A. Zeeb]

On Mar 19, 2011, at 6:37 AM, George Neville-Neil wrote:

Hey,

> I believe it's time for us to upgrade our sysctl values for TCP sockets so that
> they are more in line with the modern world.  At the moment we have these limits on
> our buffering:
> 
> kern.ipc.maxsockbuf: 262144
> net.inet.tcp.recvbuf_max: 262144
> net.inet.tcp.sendbuf_max: 262144
> 
> I believe it's time to up these values to something that's in line with higher speed
> local networks, such as 10G.  Perhaps it's time to move these to 2MB instead of 256K.
> 
> Thoughts?

Yes, did you ever commit a change?  I would even go further up to 4M.

300ms x 100Mbit/s =~ 3.6M  which is about what I can get here as residential customer here as you can probably get in Japan, and that's about 300ms from some parts of Europe.

Equally it would allow me to get Gbit/s throughout most parts of the continent here and it's still 400Mbit/s East-to-West coast in theory if I got the maths right.

In addition to Gordon's values:
I think the current OSX maximum send/recvspace values you can set are around 3720000.  The defaults are even more abysmal than FreeBSD's and I have yet to figure out to make the changes persistent over a reboot but ELIST.

So all in all I think the 2M are a save bet at least.

/bz

-- 
Bjoern A. Zeeb                                 You have to have visions!
         Stop bit received. Insert coin for new address family.