Subject: Re: adding mbuf member
To: None <>
From: Michael C. Richardson <>
List: tech-net
Date: 01/30/2000 14:31:50
>>>>> "Jun-ichiro" == Jun-ichiro itojun Hagino <> writes:
    >>> For keeping IPsec decryption history and other information, I would
    >>> like to add one variable into mbuf header (M_PKTHDR), like below.
    >>> this will let us attach extra mbuf chain to mbuf.
    >> I think that this is the right way to do this...  Is there a way to
    >> allocate the aux chain in the mbuf itself when external clusters are
    >> used?

    Jun-ichiro> You mean reusing MH_databuf for aux data when the mbuf is a
    Jun-ichiro> cluster mbuf? ((m->m_flags & M_EXT) != 0) I think that

  Yeah, but perhaps just make the decision when allocating the aux data.
The trend as far as I can tell, is to make external clusters used as often
as possible since they avoid a data copy for packets bigger than the
threshold. As such, the mbuf itself is wasted, and allocating a second seems
silly to me.

   :!mcr!:            |  Cow#1: Are you worried about getting Mad Cow Disease?
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