Local rsync disk to disk slow

Michael Lemke lemkemch@t-online.de
Sun Nov 4 12:59:00 GMT 2018

I am copying a large directory tree from one internal disk to another USB 3 connected disk on the same computer with this rsync line:

rsync -ahPvzHA --delete /d/Images /q/

This copies files at a rate of 20MB/s. If I copy the same tree with Windows Explorer I get about 90MB/s.

Why is this? The chosen options don't seem to affect the result much.

I noticed three rsync processes one of which is CPU bound at a single core and therefore limiting the performance. This process reads the source files. The other two rsync processes don't consume a noticable amount of CPU time and one of them writes the destination files.

Are there any options to speed up the process? The reason I use rsync is to preserve hard links.

Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

More information about the Cygwin mailing list