[CentOS] rsync stuck at +- 50 MB/s, cp and scp are +- 200 MB/s

Hi,

i have two servers, connected to to the lan by 10Gb with 10Gb and DAS
hardware raid.

Each system con read and write locally or to the 10G iscsi by more than
200 MB/s.

Now I have to transfer backups form A to B and doing this with rsync
always stuck at +- 48-50MB/s no matter which options, compressions,
encryption etc I use. Even the plain default rsync is at that 50 Mb limit.

coyp by scp goes up to 200 MB/s.

Copy from and to my workstation with scp from or to both servers is at
1Gb limit (so +- 100 MB/s)


Why is rsync stuck at +- 50 MB/s ? Any suggestions hints ...

	Thanks and regards . Götz

-- 
Götz Reinicke
IT-Koordinator

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E-Mail goetz.reinicke at filmakademie.de

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