Re: Gb Ethernet

[DrFranken <midrange@xxxxxxxxxxxx>]

Short answer: Yes. But then you knew that. :-)  In this situation I 
would expect you'd get 900Mb+ and probably very close to the full Gb. 
There is something like 3% overhead in TCP/IP and Ethernet Framing so 
the limit would be approximately 970Mb/s.

You are using an aggregated line on the Target system so I would focus 
there first. First question is what is the physical hardware being 
aggregated? If it's ports in the 181C remember those aren't supported 
for aggregation unless you dedicate the entire port to an LPAR. 
Something in the cover letter about "Not being sure the packets get to 
the correct LPAR..." and that seemed bad for throughput.
	
        - Larry "DrFranken" Bolhuis

www.frankeni.com
www.iDevCloud.com
www.iInTheCloud.com

On 1/10/2013 8:44 AM, rob@xxxxxxxxx wrote:

> Shouldn't I be getting a lot better throughput?
>
> Help me out with my math.  I've got an Ethernet line on 1 lpar talking to
> an Ethernet line on another lpar.  They both say:
> Current line speed . . . . . . . . :   1G
> Current duplex . . . . . . . . . . :   *FULL
>
> Target system:
> Resource        Type
> CMB03           268C
>    LIN04         6B26
> Source system:
> CMB30           181C
>    LIN06         181C
>      CMN242      181C
>
> They are both on our same 10.17.6 subnet.
>
> I FTP'd a sizeable file and got these results:
>
> Size, in bytes, of save file:  13,458,505,728
> Seconds to perform transmission:        2,222
> Bytes/sec:  6,056,933.271
> bits/byte:  8
> bits/second:  48,455,466.167
> Gb/bits:  0.000000001
> Gb/sec:  0.048455466
>
> iNav's Management central says lan utilization was minimal.
> iNav's says percent busy of disk was minimal.  (currently 2-7%)
> Source system has 64 disk arms.
> Target system is a guest on the source.  It has 6 equal "arms".
>
> Shouldn't I be getting a lot better throughput?  After all, 0.05 is not
> 1Gb.
>
> I am not interested in any virtual ethernet backplane type solution due to
> some H/A concerns.
>
>
> Rob Berendt