By: Carlos Puchol

Carlos Puchol — Sat, 17 May 2008 19:52:39 +0000

Hi!
What version fo Mac OS X do you have?
We’re interested on this to recommend it as a tip to our user group (Amahi Linux Home Server).
I experience some delays when selecting access to my Amahi LHS, something like 3 seconds to “connect”. Performance is ok, though it seems slow, so I wanted to try it.
So far we have tried it with 10.5.1, however, the difference is not noticeable with a value of 0.
The previous value was 3. We set it to 0.
HOWEVER, we tried with a different machine, with 10.5.2 in it, and it was very snappy!
Carlos

By: John Martinez

John Martinez — Thu, 01 Jun 2006 18:38:32 +0000

This didn't work for me, but setting the sysctl parameter net.inet.tcp.delayed_ack to 0 did! For me, the results were dramatic: drag-and-drop of a 100MB .wav file from the samba server took 45 minutes before the fix, and < 2 minutes after the fix. Wahoooo! Found the info here: http://julipedia.blogspot.com/2006/02/samba-performance-under-mac-os-x.html [in case that link vanishes, here's the short version: use 'sudo sysctl -w net.inet.tcp.delayed_ack=0' on command-line to try it (persistent until reboot) and put the line 'net.inet.tcp.delayed_ack=0' in /etc/sysctl.conf to fix it 'permanently' -- note: I haven't tested the latter yet. I had to create the sysctl.conf file, and haven't rebooted yet] and a good discussion of *why* it works, starts at the bottom of that same blog entry, then links to the crux of the problem here: http://mail-index.netbsd.org/tech-net/2003/01/28/0004.html [It's a TCP bug inherited from the FreeBSD stack - the same bug was fixed in NetBSD back in 1997, and Apple has known about it since before Jaguar release] Apologies for the lack of formatting - couldn't figure out how to get paragraph spacing on this blog.

Comments on: OS X to Samba slow performance

By: Carlos Puchol

By: John Martinez