Subject: Re: namei caching of newly created files?
To: None <tech-perform@NetBSD.org, tech-kern@NetBSD.org>
From: Luke Mewburn <lukem@NetBSD.org>
List: tech-kern
Date: 01/20/2005 14:34:38
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On Wed, Jan 19, 2005 at 05:47:31PM -0800, Bill Studenmund wrote:
| Becasue we don't build in-kernel lists of files in the directory, we ha=
ve=20
| to do a full search (O(n)) of the directory to see if the name is or is=
n't=20
| there already.
FreeBSD implemented UFS_DIRHASH a while ago:
http://docs.freebsd.org/cgi/getmsg.cgi?fetch=3D685987+0+archive/2001/cvs-a=
ll/20010715.cvs-all
NetApp did the same thing for their WAFL file system over a decade ago:
http://www.netapp.com/tech_library/3006.html
We should just lift the working UFS_DIRHASH implementation from FreeBSD.
Three years ago I did a work-in-progress port of UFS_DIRHASH from FreeBSD
but I didn't finish it. I have the code around somewhere.
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