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Subject: Re: mbuf and MINCLSIZE 
From: Jun-ichiro itojun Hagino <itojun@iijlab.net>
Date: Thu, 02 Nov 2000 13:07:53 +0900
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>> 	101 meaning MHLEN + 1, right?  on KAME IPv6 merge, we happened to
>> 	do that.
>didn't we move to 256-byte clusters some time ago, hence
>MHLEN is larger than that ?

	that is not the point.  traditionally MINCLSIZE was MHLEN + MLEN + 1,
	and it made drivers to emit:
		MHLEN mbuf (len <= MHLEN)
		MHLEN mbuf + MLEN mbuf (len <= MHLEN + MLEN)
		MCLBYTES cluster mbuf (len > MHLEN + MLEN)
	Richard proposes to move MINCLSIZE to MHLEN + 1, and will effectively 
	make drivers to emit:
		MHLEN mbuf (len <= MHLEN)
		MCLBYTES cluster mbuf (len > MHLEN)
	the latter stragegy will save us from m_pullup.

itojun


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