Re: namei caching of newly created files?

Luke Mewburn <[email protected]> Thu, 20 Jan 2005 14:34:38 +1100
Newsgroups gmane.os.netbsd.devel.kernel,gmane.os.netbsd.devel.performance
Message-ID <[email protected]>
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 have 
  | to do a full search (O(n)) of the directory to see if the name is or isn't 
  | there already.

FreeBSD implemented UFS_DIRHASH a while ago:
	http://docs.freebsd.org/cgi/getmsg.cgi?fetch=685987+0+archive/2001/cvs-all/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.
signature.asc (application/pgp-signature, 186 B)
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.6 (NetBSD)

iD8DBQFB7ybOpBhtmn8zJHIRAoh7AJwJJ8PuRAgvvNnL9wli/j4P3HGyFgCfZEH3
4x8nUVQueG7PLVZ8tOb/YpU=
=no9o
-----END PGP SIGNATURE-----