How to make rsync faster?

Craig Hammond craig at
Thu Nov 15 22:57:22 GMT 2007

I'm no rsync guru my any means, but two things spring to mind.

Use the -t option to stop all the spurious check summing.

Split your script into multiple scripts, each with a share of host
Run each in parallel. Multiple rsyncs can run on the one box


-----Original Message-----
From: at
[ at] On
Behalf Of Tang, Clayton (Yiqi)
Sent: Friday, 16 November 2007 6:09 AM
To: rsync at
Subject: How to make rsync faster?

I manage 250+ redhat linux boxes. The boxes are all setup the same way.
On a daily basis, we sync the app directory which is about 30gb out to
all hosts. The daily delta is actually less than 1gb, but since I can't
be sure if any individual box was tempered during the day, I always do a
full sync. On a monthly basis, we run with "--delete" to clean out the
stale files on the hosts.

The command I use daily is: "/usr/bin/rsync -a -e ssh", with a ksh for
loop on the 250+ host names
The version is: "rsync  version 2.5.7  protocol version 26"

Since rsync must do a chksum on the local and remote box on all files,
the whole sync process takes over 2hrs even if nothing was changed.

My questions are:

1) I know I have an old version, are there performance improvements in
the later versions? I am not the SA, the process to request a new
install is lengthy.

2) Is there a "parallel rsync" program? Looping 250 times to invoke
causes rsync to checksum the local files 250 times, which is a waste of
resource. Can "parallel rsync" be considered for a future version?

3) Are there better ways to achieve what I need to do with rsync or
another tool?

Thank you,

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