>>>>> "Dave" == Dave Kleikamp <[EMAIL PROTECTED]> writes:
Dave> It's a data structure I call the directory index. It's Dave> associates a fixed position with each entry in the directory, so Dave> that directory traversals resume at the right point even when Dave> changes are made to the b+-tree. ... It slowly grows every Dave> time a file is created, but does not shrink when files are Dave> deleted. It is reset to zero if a directory is completely Dave> emptied, but that doesn't usually happen. After read that and thinking about it a bit, I think I recall having known that in the past. Apologies for the dupe. That said, some tests show that it is causing a noticable slow down, by way of a significant increase in io wait. Dave> I can look into a fix, either some mechanism to reuse old Dave> positions, or something to remove the directory index and Dave> rebuild it when too much space is wasted. That would be most cool. Right now, after having tested all of the major filesystems on the laptop, I have only two issues with jfs. The slow down over time, which seems likely to be due to the unchecked growth of busy dirs, and a bug in grub's jfs stage2 which prevents kernels larger than some magic size from booting. (No one else can duplicate the bug so I have to presume it is specific to the stage2.) The latter I can eventually work arond once I have hardware to backup the drive and create a /boot partition. Fixing the slowdown would be a huge win. Reusing old positions sounds optimal. -JimC -- James Cloos <[EMAIL PROTECTED]> OpenPGP: 1024D/ED7DAEA6 ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Jfs-discussion mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/jfs-discussion
