Subject: Re: free page management
To: Jason Thorpe <>
From: Noriyuki Soda <>
List: tech-kern
Date: 03/13/1997 08:39:24
>>>>> On Wed, 12 Mar 1997 12:52:16 -0800,
	Jason Thorpe <> said:

> Anyhow, the diffs are attached below.  Please sanity-check them and
> comment :-)

FreeBSD-2.1.X keeps the information in PG_FREE bit of struct vm_page::flags,
rather than bitmap, and it doesn't require extra memory.
(My client made/uses private patch to implement vm_page_alloc_contig()
 in this way.)
Is there specific reason not to do so ?

(FreeBSD-2.2.X and FreeBSD-current keep it differently, though.)