Rsync incredibly slow in Cygwin - am I doing something wrong?

2

I am trying to back up my C: and D: drives (each 1 TB, C: has around 210 GB of data on it, D: has around 345 GB on it) onto a 3 TB external HDD using Cygwin in Windows 8.

I am doing this with rsync.exe -avz --progress /cygdrive/c/ /cygdrive/f/Backup/c/ and I let it run over night and just checked it and it has only copied around 33 GB. That is 33 GB in about 6 hours. I had done it the night before using cp -rf and it finished overnight (that is around 210 GB in the same amount of time or less). I chose to redo it using rsync so that I future backups would not take as long.

Am I doing something wrong? Does rsync not work well in cygwin? I thought it was the same performance as cp.

If I did want to go back to using cp, what is the best command to duplicate rsync (all I want to do is to copy the file if it is not there or if the source file is newer).

drjrm3

Posted 2014-03-12T15:17:06.073

Reputation: 1 164

Answers

1

I am not sure WHY, but I found a solution on the cygwin mailing list archive.

Adding the -W argument to rsync took my transfer speed from 200kBps to 1.5MB/s.

mrkmg

Posted 2014-03-12T15:17:06.073

Reputation: 29

Thank you, that -W option fixed it for me too. It's indeed five or six times faster. – laurent – 2016-03-13T19:40:22.183

Strange, on my Windows 10 machine the -W flag to cygwin rsync.exe actually makes it run even slower! – mcandre – 2017-12-16T15:10:33.970

@mcandre, if you are using ssh, the -W flag would likely be slower. Are your source and destination both local? – mrkmg – 2017-12-31T23:25:32.770

Asked: 2014-03-12T15:17:06.073

Viewed: 2 630 times

Active: 2015-04-23T22:42:15.333