Hi, On Wed, Oct 01, 2008 at 10:46:18PM +0200, Hans Verkerk wrote: > I faced similar problems on 3750 platform and also resolved it with > etherchannels (under time pressure). I took some time reading QoS > details of 3750 platform, but did not take time to test in real world.
OK, I've done quite some testing, tuning "to the extreme"... Queueset: 1 Queue : 1 2 3 4 ---------------------------------------------- buffers : 1 5 93 1 threshold1: 100 200 1600 100 threshold2: 100 200 2400 100 reserved : 50 50 90 50 maximum : 400 400 3200 400 (and all traffic is mapped to queue 3). > *** Maybe *** your problems are caused due to lack of Tx queue buffers. > By default all buffers are equally shared over all four Tx queues: It definitely looks like it - by tuning the buffers, I can change the drop rate between "too high" and "catastrophic". Without mls qos, it seems to just give the port *all* the buffers, with no fancy "take away a few buffers for this and that" schemes going on - so the drop rate is actually lowest if I turn *off* mls qos... As a next test, I'll try to move around machines between port ASICs - maybe things improve if ingress and egress ports are (not) on the same ASIC. We'll see. gert -- USENET is *not* the non-clickable part of WWW! //www.muc.de/~gert/ Gert Doering - Munich, Germany [EMAIL PROTECTED] fax: +49-89-35655025 [EMAIL PROTECTED] _______________________________________________ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/