Re: Gb Ethernet

[DrFranken <midrange@xxxxxxxxxxxx>]

Dan,

	That's curious. I have dozens of partitions on POWER5 6 & 7 and IBM i 
6.1 and 7.1 with the default IPV6 settings and I've not encountered any 
issues. I just tested an FTP between two i7.1 partitions (with IPV6 
active) and got pretty good speed:

169478144 bytes transferred in 1.726 seconds. Rate 98214.836 KB/sec

Now the only IPV6 address active is the loopback address. Did you have 
more than that configured? Was DNS configured to use IPV6?

I'm interested to understand where the bottleneck is.
	
        - Larry "DrFranken" Bolhuis

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

On 1/10/2013 10:27 AM, Dan Kimmel wrote:

> Make sure you're either fully configured for IPV6 or disable it. I've had lots of performance problems with newer machines and IBMi versions. 6.1 and 7.1 have IPV6 enabled by default. If you aren't fully configured for IPV6 (ie an IPV6 DNS server on the machine) the IP stack spends an inordinate amount of time trying to find the other machine. It seems that time is spent on EVERY packet. Most of my experience is with Java applications which always favor IPV6 unless explicitly configured to prefer IPV4. I don't have much experience with the FTP client and server on IBMi, so this may not actually be a factor. But it's something to check.
>
> -----Original Message-----
> From: midrange-l-bounces@xxxxxxxxxxxx [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of rob@xxxxxxxxx
> Sent: Thursday, January 10, 2013 7:44 AM
> To: midrange-l@xxxxxxxxxxxx
> Subject: Gb Ethernet
>
> 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