Re: Much improved sosend_*() functions



John-Mark Gurney wrote:
Andre Oppermann wrote this message on Fri, Sep 29, 2006 at 23:59 +0200:
Just don't overengineer the stuff. Mbufs are only used temporarily and
a bit theoretical waste is not much a problem (so far at least).

Well, I beg to differ... most gige cards grab mbuf+cluster for every
single ring buffer they have.. which is usually 512... so every gige
interface for the most part consumes 1meg of memory that is not
reusable... because if we run out of mbuf+clusters to replace in the
receive ring, we will not tap into the 1meg of mbuf+clusters available
to us... so, if you have a quad gige, that's 4megs wasted, plus w/ the
fact that we could only use ~65% of that memory, that's a lot of memory
wasted...

The problem is the network cards again. Only a few allow different
rx rings to be used (for example bge(4)) where you can have multiple
mbuf (+cluster) sizes and the card choses the smallest fit at receive
time.

Yeh, everyone says you have gigs of memory, but do we really want to
be known as the wasteful OS?

--
Andre
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