Editing MH Message Handling System (section)

== Performance ==

The performance of MH is very much dependent on the file system and other features of the operating system that it runs on.  Every read of a message will require starting a separate program, a directory scan in a large directory and a file open before the data can even be accessed.  On the other hand, mailbox formats such as [[mbox]] which use a single file often require insertion or removal of data in the middle of the file when messages are read or altered and this can be a very slow procedure.  In these cases MH will be much faster.

The [[maildir]] storage format made popular by [[qmail]] and the [[Courier Mail Server]] improves upon several features first shown in MH: a separate file per message, a separate directory per mail "folder," and exploitation of [[hard link|hardlinks]] and other advanced filesystem features for improved performance in space and time.