How to be a Considerate Mail User
This document is intended to serve as a quick guide to optimal usage
of mail services provided by the Informatics Mail Server,
mail.inf.ed.ac.uk. Although mail.inf.ed.ac.uk only provides services
to staff and visitors (not to students, who should use the
Student Mail Service), some of the
Do's and Don'ts noted here apply equally well to whichever mail server
is being used.
Due to the wide variety of mailers or email clients (the program or
application that you use to read and send email), specific commands
for those programs or applications are not covered here, although
occasional commands illustrating important points may be referred to.
Good Practices
The mail service is a very important service, and below are a few
simple steps that people can take to reduce the load on the server
(and thus improve performance for everyone).
- Delete unwanted/needed messages
- Large mailboxes are the single
most performance-reducing
items on the mail server, as they take a long time to load or
to scan for message headers. Small mailboxes are much better!
Note that some mailers will hide messages that have been
marked for deletion, and so may appear to have deleted
them - when, in fact, they're still there.
Check for an "expunge" or "compact" folder
option, and use that to really delete such messages.
If you really do want to keep all that mail, then file old
messages in a mailfolder other than your INBOX. This will
make your day-to-day access to your current INBOX quicker.
- Check your spam folder
- A variation of the above. If you are using spam filtering to file away suspected
spam, then please remember to check
it! Although the spam filters catch most of the spam,
some genuine mail (known as "false positives") gets caught as
well - so it is advisable to check for legitimate messages,
and then to delete the genuine spam.
- Clear out your Sent folder
- Most mailers store a copy of your outgoing mail. If, for
example, someone sends you a 4Mb attachment which you then
forward on to someone else, not only do you have a copy of
that 4Mb attachment in your INBOX, you also have a copy in
your Sent folder. So if you don't need that extra copy,
delete it (usually, the attachment can be marked for deletion
so that when the message is copied to a folder, the
attachment is deleted).
- Trash folder
- Sometimes, when you mark individual messages for deletion,
they are not actually deleted but moved to a Trash folder. In
cases such as this, either change the delete option to
"really delete" rather than "move to Trash" (if this is
applicable for your mailer), or make sure that you
explicitly empty your Trash folder every so often.
- Save attachments in your home directory
- Don't leave large attachments in your mail folders, save
them to your home directory.
- Don't check your mailbox too frequently
- When your mailer checks to see if you have new mail, it
has to contact the mail server to do this - and if it does
this too frequently, it places an unnecessary load on the
server. Most mailers allow you to set the period of time
between these new-mail checks, and you should make sure that
your mailer only does this every few minutes - every
five minutes is good, but certainly not less than two
minutes.
- Are you leaving several mail reading clients running at once?
- In these days of broadband home connections, a few people may
leave a mailer running at home - this is also
polling your INBOX every few seconds/minutes for mail. If you
need this running as well as your work mail reader, you
should consider reducing the frequency at which it checks
(increase the time interval between checks).
- fetchmail users
- For those people that use fetchmail, use the "-e"
flag (or the "expunge" configuration option) to deal with
messages in bigger batches, not just one at a time.
Note that, if you are just using fetchmail to
download your mail so that you can sort it with
procmail, the
IMP web front end
allows you to set up arbitrary procmail
filters.
- Don't use IMP as you main mailer
- The IMP web front end was intended for occasional, remote
use. If you are reading mail within Informatics, it is
recommended that you use a proper IMAP-aware mail reader
such as pine or Thunderbird
- Use SSL
- Protect your account details, make sure you use a secure SSL
IMAP connection (IMAPS).
- Check your recipients list
- When you reply to a message, especially if it is a response
to a message sent to a mailing list or other large group of
people, make sure you are sending it to who you want
to send it to - and not (unless you want to) back to the
whole list. If a message comes round with a large attachment,
posted to a list with a large membership, replying to the
whole list and including the attachment could place an
unnecessary load on the server, and use much more disk space
than intended.
- Check your mailbox locations
- When using IMAP-aware mail readers, it is possible to store
mail in several locations, which may be on the server or in
your home directory. Storing too much on the mail server may
degrade performance and affect other users (note that some
mail readers have a folder compression option).
Several of the above items talk about checking the size of your
mail folders. Read the document www.inf.ed.ac.uk/systems/email/diskusage.html
for details on how to do this.
