Network Speed

How fast can I get my data out from the server?

It turns out there is a lot of overhead and some settings can make a difference.

Reading speed from the Microserver back to my Mac Pro. The speed is in MBs.

MTU = 1500 (default) MTU = 9000 (custom)
rsync over ssh 21.6
rsync from afp-mounted share 35.8 45.1
cp from afp-mounted share 55.1 61.6

Tweaking a simple thing like MTU makes a noticeable difference in speed in a local environment. I also observed that CPU load on the Microserver went down with the higher MTU setting.

Caution. To get the full effect of the change, you have to make sure the other machines on your network have the same MTU settings. And, changing MTU does affect other things. While it looks like my outside network connection was unaffected, I did observe some weird behavior locally. For example, XCode svn client on my desktop stopped connecting to the local svn repository using address. I switched to using localhost name instead of and everything works again.


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