Windows 7 and Windows Server 2008 R2 include an updated version of Robocopy that includes a multi-threaded copy feature.
/MT[:n] :: Do multi-threaded copies with n threads (default 8).
I’ve been using this for a while now and I’ve been seeing excellent results. Be careful with who you share a switch with though – I managed to saturate my 100Mbit switch so badly that my fellow switch neighbors started getting timeouts. My favorite usage is:
robocopy \\server\share\folder C:\Temp\folder /S /MT /Z
This copies the contents of the remote folder, with 8 threads in restartable mode – great for when you’re on a slow or unreliable link. Also note that the progress monitors don’t seem accurate in multi-threaded mode. It starts copying 8 files at once, but only shows you the progress of 1 of them.
Hi Grant,
Thanks for this post.
I was wondering, do you ever see issues with the multithread option? I’ve been trying this out, copying from remote to a local share, and it seems like robocopy is freezing up. I don’t get any console output, or output to a log.
I’m just wondering if others have experienced this behavior.
I see the same thing. The more files there are the longer it takes to begin. If you are dealing with small folders (<100 files) it is not a big deal, but with large folders it takes forever. I don't like the MT option anyway. It seems like it would cause more fragmentation and much more seeking on the read disk.
We ran some tests comparing Robocopy with and without the /MT (multithread) option with local disk, 1GbE network and 10GbE network. We tested a variety of numbers and sizes of files. I gave a presentation at our local user group meeting, and the presentation is available at www.demartek.com/Demartek_Presenting_RMWTUG_March_2011-03.html. The /MT option provides improved performance and in some cases, significantly improved performance.