mmdf is the SCO mail daemon - the files being created are probably email to be sent. If it's like Sendmail, the mail will still be running even though you killed the mmdf process. This means killing the process doesn't stop email from being created and put into the queue to be sent - it just means you can't receive mail on that server (again, assuming MMD works like Sendmail).
Check what type of files are being put into the directories - file * should list them. If they are type ascii, cat a couple of them. You will probably find they are emails. Check to see if any of the files seem to be spam. You may not have your mmdf set up properly and could be a relay for a spammer.
Killing off the mmdf probably didn't do a thing for you. And if the system is slow (and email isn't going out), then you probably have a problem with DNS (again, this is assuming that mmdf works like Sendmail) OR with someone using your system as a mail relay.
mmdf relay
MMDF overview
Quote from MMDF overview:
Quote:
After parsing the database and determining what channel the message needs to be sent through, the message is place in the appropriate queue directory. These are located in /usr/spool/mmdf/lock/home. There is one directory of the form q.<channel> for each <channel> configured. In addition, there are two other directories here: msg and addr.
The files in q.<channel> are linked to the files in addr and contain administrative information about the message like the sender, recipient and the queue. At first, it may seem odd to have duplicate files, like this. However, this makes sense when you consider the different delivery modes, or "priorities" you can configure MMDF for.