On Sun, Nov 29, 2009 at 12:02:31PM -0500, Lou Arnold wrote:
> First, this is all done at home, and not in a production environment.
> I used Fedora for a server, primarily to provide Samba shares. I noted
> the speed change when I was running Clonezilla to take hard drive
> images from another computer. The cloning software gives a active
> speed in 100's of MB per min. For Fedora it was about 650, while for
> CentOS it seems to be about 375. I did no other tests and this will
> always be one of two Linux systems on a LAN of 5 computers. One day I
> will get time to actually develop software on that system. Sorry to
> have omitted these facts at the outset. I see many of you are far more
> sophisticated in your environments.


Something is wrong with your numbers. So you use Clonezilla
to copy a disk image from one disk to another.

1) hard disk read/write speed is of the order of 50-100 Mbytes/sec (multiply by 60 for Mbytes/min)
2) on a GigE network, effective network speed is also about 50-100 Mbyttes/sec (3000-6000 Mbytes/min).
3) on a 100Mbit/sec network, the limit is 10-11 Mbytes/sec (660 Mbytes/min)
4) you see the same data rate with Fedora (650 Mbytes/min) , so I conclude that you do not have a GigE network.
5) your CentOS measurement 375 M/min does not reach even the 100Mbit/sec network speed limit, perhaps
   some other application is "stealing" network or disk bandwidth. From the hardware side,
   every computer on Earth with any disk can saturate the 100Mbit/sec network.

But lacking a GigE network, you are basically comparing the speed
of a Porsche and a Lamborgini on an unpaved gravel road.


-- 
Konstantin Olchanski
Data Acquisition Systems: The Bytes Must Flow!
Email: olchansk-at-triumf-dot-ca
Snail mail: 4004 Wesbrook Mall, TRIUMF, Vancouver, B.C., V6T 2A3, Canada