On Thu, Mar 31, 2011 at 09:13:41AM +0000, Stuart Henderson wrote: > On 2011-03-31, Otto Moerbeek <o...@drijf.net> wrote: > > On Wed, Mar 30, 2011 at 03:45:02PM -0500, Amit Kulkarni wrote: > >> In fsck_ffs's pass1.c it just takes forever for large sized partitions > >> and also if you have very high number of files stored on that > >> partition (used inodes count goes high). > > If you really have a lot of used inodes, skipping the unused ones > isn't going to help :-) > > You could always build your large-sized filesystems with a larger > value of bytes-per-inode. newfs -i 32768 or 65536 is good for common > filesystem use patterns with larger partitions (for specialist uses > e.g. storing backups as huge single files it might be appropriate > to go even higher).
So this helps a lot to reduce fsck however if you play a lot with the "tuning" parameters the only thing you tune is less speed. I played quite a bit with the parameters and the results were always worse than the defaults. > > Of course this does involve dump/restore if you need to do this for > an existing filesystem. > > > It is interesting because it really speeds up fsck_ffs for filesystems > > with few used inodes. > > > > There's also a dangerous part: it assumes the cylinder group summary > > info is ok when softdeps has been used. > > > > I suppose that's the reason why it was never included into OpenBSD. > > > > I'll ponder if I want to work on this. > > A safer alternative to this optimization might be for the installer > (or newfs) to consider the fs size when deciding on a default inode > density.
