[CentOS] network copy performance is poor (rsync) - debugging suggestions?

Hi,

I do have two centos 6.6 servers. With a "performance optimized" rsync I
get an speed of 15 - 20 MB/s

The options I use are:

rsync -aHAXxv --numeric-ids --progress -e "ssh -T -c arcfour -o
Compression=no -x"

If I copy files by smb to/from the servers I do get 60 - 80 MB/s, a dd
(r/w) on the storages attached gives 90 MB/s on the 1Gbit ISCSI (Source
Server) and up to 600MB/s on the 10Gbit ISCSI (Destination Server) storage.

Both servers have plenty of memory and cpu usage looks low.

Currently we dont use jumbo frames. Network over all usage is moderate
to low. There are no special sysctl tweeks yet in use.

As mentioned, I'm confused that even with SMB I do get 3 to 4 times
better performance.

Any hint and suggestion to track that problem down is welcome!

	Thanks and best regards . Götz

-- 
Götz Reinicke
IT-Koordinator

Tel. +49 7141 969 82 420
E-Mail goetz.reinicke at filmakademie.de

Filmakademie Baden-Württemberg GmbH
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