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Nik, excellent points about the difference between software queues and hardware queue, and about assigning larger hardware buffer thresholds!
However, I differ on the opinion that defining multiple queues is necessarily the ideal solution in this instance. When you do that, you then generally split your buffers to support the multiple queues which reduces resources for each. Often whatever traffic that is exhausting resources will then encounter buffer exhaustion even sooner. (NB: This seems to be a common issue on the 3750 series when QoS is enabled; as noted on these forums. I.e., drops are seen that were not seen before.)
On the other hand, I'm not proposing that enabling QoS features are necessarily bad in this instance either, as splitting traffic into different queues can protect other traffic from drops caused by the bandwidth intensive traffic, Doing it "right" can be more complex and, again, for brief transient bursts might be counter productive, at least for simply reducing drops. (NB: The QoS approach Nik is recommending can offer other advantages, such a reducing latency for some traffic, etc., and you can even "tune" drops, but also with additional complexity. For example, Nik mentions tuning buffers from the common pool, and this can be done, but with the risk of insufficient buffers for other interfaces.)
