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Subject: Re: mbuf question
From: Rui Paulo <rpaulo@FreeBSD.org>
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Date: Sat, 15 Mar 2014 21:31:52 -0700
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To: Ian Lepore <ian@FreeBSD.org>
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On 15 Mar 2014, at 16:13, Ian Lepore <ian@FreeBSD.org> wrote:
> How about an optimization that puts tags in that area when it's
> available to avoid the allocation overhead?  I don't know much about =
the
> network code, so maybe that's not a sensible idea.

The problem with mbuf tags is that they are not fixed size, so they =
can't easily use UMA (although they use malloc which is backed by UMA, =
but the performance is lower).  If tags are not an option, I suppose =
Hooman could use fields from struct pkthdr, but this might come with =
risks if the code is not in the tree.=20

--
Rui Paulo