I try to not reblog too much, but since this is a link to an info site not a blog entry it doesn't count, mkay? Ttoday's reading comes from the book of ESNET. The R&E guys know a thing or two about stack tuning. This one is a little long in the tooth (still talks about FreeBSD 7 and 8 and Linux kernel 2.6) but has some fundamental truths in it including watching out for your NIC offload and links to some interesting software.
Joe-Bob says check it out.