On 04/14/2014 01:41 AM, Russell Miller wrote: > HOWEVER. When a directory grows too large, the OS can take a long time > to seek through the directory, which can cause its own set of > problems. And this makes cleaning out a maildir directory selectively > a real pain. Maildir really could do with a hashing mechanism. Worse, if the dir gets too big, even after files are deleted it can be very slow. I had one case with >1,000,000 messages in a single maildir (spam on steroids, was getting 80,000 messages per hour overnight); after it was cleaned out to <1,000 messages it still took several minutes to ls the dir, and the machine's responsiveness went through the floor. Copying to a new dir and renaming fixed the slowdown; the directory was >50MB (the directory itself, not its contents). I'd rather have mbox for plain text e-mail storage, and a database for something really high performance.