My Mac Pro arrived. However, one thing I noticed immediately is that I could copy files at around 30MB/s across my gigabit network if the Mac Pro was talking to one of my Infrant ReadyNas boxes (AFP), but as soon as I tried to copy to or from Windows XP using SMB, network traffic slowed to a crawl. I was unable to transfer data faster than 4MB/s, which is 1/2 of real-world 100Mbps. Luckily, I found a fix late last night.
I did some investigating online and discovered that some Windows boxes don’t like ACK delay. I also read that the slow network performance might also be an IPv6 compatibility issue. So here’s what I did:
- disabled IPv6 on Mac OS X (System Preferences->Network->Configure->Configure IPv6->Off)
- uninstalled ipv6 on Windows XP via command line: netsh interface ipv6 uninstall
- on MAC OS X, set ACK no delay by adding
socket options = TCP_NODELAY IPTOS_LOWDELAY to your /etc/smb.conf file.
Now I’m getting around 30MB/s when copying between MAC OS X and Windows XP boxes, which is good. But man, what a pain in the ass to get these machines talking.