Re: [PATCH] mlx4_en: map entire pages to increase throughput

From: Rick Jones <redacted>
Date: Mon, 16 Jul 2012 10:27:57 -0700

That seems rather extraordinarily low - Power7 is supposed to be a
rather high performance CPU.  The last time I noticed O(3Gbit/s) on
10G for bulk transfer was before the advent of LRO/GRO - that was in
the x86 space though.  Is mapping really that expensive with Power7?

Unfortunately, IOMMU mappings are incredibly expensive.  I see effects
like this on Sparc too.