cbwfq class-default queue length

Unanswered Question
Jul 15th, 2008
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Our implmentation uses cbwfq in WAN links.

i did not find the information about queue length when i use fair-queue in class-default.

Any idea?


the queue limit is used by tail drop.

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Overall Rating: 5 (1 ratings)
KAROLY KOHEGYI Tue, 07/15/2008 - 06:37
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We have 7200 platform

we know what flow means.

Are there any limitation for queue length per flow ?


lee.reade Tue, 07/15/2008 - 06:46
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You can increase this using the fair-queue VALUR and you can use the queue-limit command also, to specify when to use tail drop.

Ie fair-queue 100

queue-limit 50

would mean that you could have 100 dynamic WFQ queues and 50 packets limit within each, after this, then the rest get tail dropped.

You could increase this value to max 4096 for dynamic queues, or not use the queue-limit command which would suggest no limit of packets per flow.



KAROLY KOHEGYI Tue, 07/15/2008 - 06:55
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very thanks.

i unterstood the queue-limit command in wfg.

you wrote

which would suggest no limit of packets per flow

is it sure ????

lee.reade Tue, 07/15/2008 - 07:04
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I dont have access to a box to verify but, looking at the command ref, the congestion discard threshold can be to specify when to drop packets, when configured on the physical interface.

But when using cbwfq then you cant do this.

The best way to check is to issue show service-policy interface x/x when you have applied it, and see what it says.




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