On Sun, 2006-08-20 at 12:48 +0100, Ron Yorston wrote: > Andrew Morton <akpm@xxxxxxxx> wrote: > >Been there, done that. The problem was that hanging onto the preallocation > >will cause separate files to have up-to-seven-block gaps between them. So > >if you put a large number of small files in the same directory, the time to > >read them all back is quite significantly impacted: they cover a lot more > >disk. > > The preallocation is only held while the file is open, so there will only > be gaps between files that are open simultaneously. If they're created > sequentially there will be no gap. > > This issue exists even with the current code. > > The patch will have a small effect. With the current code an open file > will lose its preallocation when some other process touches the inode. > In that case a subsequently created file will follow without a gap. As > soon as the open file is written to, though, it gets a new preallocation. > - maybe porting the reservation code to ext2 (as Val has done) is a nicer long term solution.. -- if you want to mail me at work (you don't), use arjan (at) linux.intel.com - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
