Slow Samba read performance Mac OS X

Operating Systems: Mac OS X 10.4.x
Published:         13.04.2007, Marc Petitmermet
Revised:           17.04.2007, Marc Petitmermet: added automator application

Problem

• downloading from samba server to Mac OS X client is slow
• uploading to samba server from Mac OS X client is fast

Easy Solution

Download, unzip and run our Automator Application: delayed_ack.app.zip

This application does the following:

• show an info panel
• ask for an administrator account and password
• sets net.inet.tcp.delayed_ack=0
  (This tells the TCP stack in the kernel to not delay packet acks.)
• create the file /private/etc/sysctl.conf with content net.inet.tcp.delayed_ack=0.

Manual Solution

1. start Terminal.app
2. become administrator (your administrator account name may be different):
   

   su - administrator

3. set net.inet.tcp.delayed_ack=0:
   

   sudo sysctl -w net.inet.tcp.delayed_ack=0

4. make the change permanent by creating the file /private/etc/sysctl.conf
   

   echo 'net.inet.tcp.delayed_ack=0' >> /private/etc/sysctl.conf

Source: http://www.mostlygeek.com/node/85