[c-nsp] Tail drops on ME3600 with shaping policy

[Šturmankin Miroslav]

I would be careful with setting queue-limit to 100 percent as default in all policy-maps. We had an issue on me3600cx where applying queue-limit percent 100 to one 1G port would cause drops on other 1G and 10G ports (though it fixed drops on that particular 1G interface we were seeing without queue-limit applied). We had to lower the number to 50 to get rid of the drops on all of the interfaces (was hadling the case through TAC).

Regards/S pozdravom,

Miro Sturmankin
Oddelenie sietovej architektury
SWAN, a.s.

-----Original Message-----
From: cisco-nsp [mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of James Bensley
Sent: Wednesday, September 16, 2015 2:50 PM
To: cisco-nsp at puck.nether.net; CiscoNSP List
Subject: Re: [c-nsp] Tail drops on ME3600 with shaping policy

On 16 September 2015 at 10:10, CiscoNSP List <CiscoNSP_list at hotmail.com> wrote:

Spyros mentioned about over-buffering. I don't see any problem with this, with "queue-limit percent 100" the IOS resource manager will allocate more buffers to the port as requried (as throughput
increases) and de-allocated them when they aren't need, otherwise you couldn't have more than one traffic class on the entire switch with "queue-limit percent 100" configured. The idea/approach I use is that the command can be applied everywhere and just let the ASIC handle it.
This has removed tail-drops for us without any further issues or repercussions.

Cheers,
James.
_______________________________________________
cisco-nsp mailing list  cisco-nsp at puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/