This is the mail archive of the
mailing list for the Cygwin project.
RE: Cygwin Rsync/SSH performance issue
- From: "Jan Alphenaar" <jan dot alphenaar at dotcolour dot com>
- To: <cygwin-developers at cygwin dot com>
- Date: Tue, 16 Feb 2010 16:45:38 +0100
- Subject: RE: Cygwin Rsync/SSH performance issue
I did some more testing on this and figured out that rsync/ssh is only
taking the full cpu if the bandwidth allocated to the session exceeds the
true bandwidth available on the link.
For example, if the uplink is 128KB/s and I pass in the --bwlimit=24
parameter the cpu is around 0%. Even --bw-limit=126 does not take 100% cpu,
but --bwlimit=132 does.
Would this be because of packet loss on the link and packets have to be
retransmitted ? I will do a quick test tonight with rsync/ssh between two
linux boxes, see what that gives me.
Van: Jan Alphenaar [mailto:firstname.lastname@example.org]
Verzonden: dinsdag 16 februari 2010 11:34
Onderwerp: Cygwin Rsync/SSH performance issue
I am using rsync/ssh to copy files from my computer to my server and
everything seems to function as expected, except performance.
During a file transfer on my home computer (Intel I7) there is not a
noticeable CPU load. But on other (older) machines the rsync/ssh transfer
consumes all CPU resources on the sending side. I noticed there are other
questions regarding this subject in the archives, but I could not find a
solution for this. Also throttling the bandwidth to a lower value is not
helping to reduce the CPU load.
I am using quite a basic command to sync my files:
rsync -e ssh * <user>@<server>:/data
The versions of the software I am using are:
Was anybody able to resolve this ?
Any help is greatly appreciated.