-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Wed, Feb 17, 2016 at 02:03:25PM -0800, David Christensen wrote: > On 02/17/2016 11:13 AM, Chris wrote: > >is it possible to save 5000 folders in the same directory (ext4 FS) > >without any performance issues? > > > >It's a Maildir structure with a .-separator, e.g. > > > >/var/vmail/public/folder1 > >/var/vmail/public/folder1.subfolder1a > >/var/vmail/public/folder1.subfolder1b > >... > > > >Would it be better to use "real" subfolders with / as separator? > > The Wikipedia ext4 article indicates that 5,000 subdirectories > should be possible: > > https://en.wikipedia.org/wiki/Ext4 > > Increasing the 32,000 subdirectory limit > > In ext3 a directory can have at most 32,000 subdirectories. > Ext4 allows an unlimited number of subdirectories.[16] To allow for > larger directories and continued performance, ext4 turns on HTree > indexes (a specialized version of a B-tree) by default. ... > > > As for performance, my WAG is that file system directory accesses > are a tiny fraction of the overall workload for normal mail server > operations, so you could pick either directory structure and > performance will be essentially the same. If you need to quantify > performance, then you'll have to find or devise meaningful > benchmarks.
Of course (and this goes also for my other post) don't expect an "ls -l" on such a monster directory to be fast. And be prepared for shell globbing (e.g. "rm *.bat") to go haywire from time to time. But that's not the file system's problem. Thats not how you use such monster dirs :-) regards - -- t -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iEYEARECAAYFAlbFeksACgkQBcgs9XrR2kZKPgCeP/qSsuG9qL0UDJlOJv+8AsrB RgkAnA2e9akML/l7AF4/ypB2cqJG9LNw =jrY0 -----END PGP SIGNATURE-----
