Dave Chinner <david@xxxxxxxxxxxxx> wrote: > > What I'd like to do is remove the fanout directories, so that for each logical > > "volume"[*] I have a single directory with all the files in it. But that > > means sticking massive amounts of entries into a single directory and hoping > > it (a) isn't too slow and (b) doesn't hit the capacity limit. > > Note that if you use a single directory, you are effectively single > threading modifications to your file index. You still need to use > fanout directories if you want concurrency during modification for > the cachefiles index, but that's a different design criteria > compared to directory capacity and modification/lookup scalability. I knew there was something I was overlooking. This might be a more important criterion. I should try benchmarking this, see what difference it makes eliminating the extra lookup step (which is probably cheap) versus the concurrency. David