[c-nsp] WS-X6704-10GE, WS-X6708-10GE

[Artyom Viklenko]

On 02.03.2012 13:07, Łukasz Bromirski wrote:
> On 2012-03-02 09:13, Artyom Viklenko wrote:
>
>> I'm tring to clarify my understanding of switching paths on these
>> line cards. From one point of view, Cisco docs says that if the
>> traffic should ingress via one port on the line card and then
>> should egress through another port on the same line card it will
>> never leave this line card. So it will be switched via internal
>> bus. Right?
>
> No, and if it says so somewhere, please point it to the doc team
> to fix it.
>
> Both 6704 and 6708 have two complex of Fabric ASICs.
> The 6708 you can see on figure 21 here:
> http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps708/prod_white_paper0900aecd80673385.html
>
>
> The port mappings for Fabric ASICs should be found in the hardware
> installation notes under the 'Switch fabric connections' in the
> tables for specific LC:
> http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/hardware/Module_Installation/Mod_Install_Guide/02ethern.html#wp1048010
>
>
> Essentially, traffic from one Fabric ASIC to the ports on the
> other Fabric ASIC will go over the fabric itself. Only traffic
> belonging the the same Fabric ASIC will be switched locally if of
> course there's a DFC installed.

ok. Now I see

Switch Fabric Resources
   Bus utilization: current: 13%, peak was 51% at 21:31:26 EET Sat Feb 
18 2012
   Fabric utilization:     Ingress                    Egress
     Module  Chanl  Speed  rate  peak                 rate  peak 

     2       0        20G   23%   46% @22:57 30Jan12   18%   49% @22:02 
31Jan12
     2       1        20G   21%   49% @20:08 01Feb12   25%   46% @20:14 
25Feb12

I.e. 4,6 Gbps on channel 0 and 4,2 Gbps on channel 1. No DFC on module.
Total input on all four 10GE ~ 19 Gbps. Fabric switching only 8,8 Gbps.
Similar approach I see on 6708 with DFC. Some part of traffic goes via
fabric and some in line card itself.

AFAIK, presense of DFC influence only forwarding decisions process (and 
policyng, for example) but not on moving traffic itself?

Anyway, if traffic should be switched in ASIC what is the limitations
in terms of bandwidth or PPS?


-- 
            Sincerely yours,
                             Artyom Viklenko.
-------------------------------------------------------
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