Darkwing Email Slow? What You Can Do to Help Speed Things Up

Dan Albrich
Manager, Microcomputer Services
dalbrich@uoregon.edu

In recent weeks some Darkwing users may have noticed unusually slow response times when trying to access their mail.

This slowness is a bit of a conundrum because Gladstone has over twice as many users as Darkwing (29733 vs. 12497) and is similarly equipped, yet it does not exhibit the same behavior. What we do know about the problem is that it is related to the frequency of disk access requests, and much of that disk load is associated with email. We believe the majority of the problem is associated with a comparatively small number of users.

Users Who Are Unlikely to Be Part of the Problem…

Mail users who are extremely unlikely to be contributing to Darkwing's slowdown include those who:

1. check their email on Darkwing over a dialup modem connection
2. check their email on Darkwing using web email
3. use ssh to connect to Darkwing and then read their email using a command-line email program such as Pine

Users Who May Be Part of the Problem…

We believe those users who may be contributing to Darkwing's slowness satisfy all three of the following specific characteristics:

1. They set their email program to check frequently for new email (sometimes as often as once a minute), or check their email from multiple locations at the same time (e.g., they have their computers set to automatically check their email from their office and from a machine at home simultaneously).
   
   
2. They have a large default "inbox" containing many messages (or a smaller number of very large messages).
   
   
3. They employ a mail program that uses the POP3 protocol to access mail messages (e.g., Eudora, Outlook, Mac OS X Mail).

This behavior can be a problem because every time a mail program uses POP to access email, the entire default inbox gets read. If there are 11MB of mail in that default inbox, and that mailbox is checked sixty times an hour, that represents 660MB of disk I/O for that user, or an amount of data equal to the entire contents of a CD-ROM. Multiply that by thousands of users, and you can see how that can quickly become a problem.

What You Can Do to Help:

1. Configure your email program to check mail only when you tell it to--or, if you prefer automatic connections, set the mail check interval to 15 or 20 minutes. For instructions on how to do this, go to http://micro.uoregon.edu/email/efficiency/ or call 346-4412
   
   
2. If you have thousands of messages in your inbox, move them to another folder in your mailbox. If you don't have time to sort them all, you can simply create a folder with a name indicating the date range, such as "Jan03toOct03." Moving mail out of your inbox to any other mailbox will greatly help to alleviate the problem.
   
   
3. Consider using IMAP as your connection method instead of POP (see http://micro.uoregon.edu/email/popvsimap.html for a description of POP and IMAP). IMAP clients tend to open a single connection and maintain it instead of reconnecting to check for new mail. POP clients are more likely to connect, check for new mail, and disconnect at regular intervals, resulting in higher overhead. However, note that Eudora's support for IMAP isn't perfect, especially for high-volume email users. In addition, some users may simply prefer the way their mail program works in POP mode.

Feel free to contact us (microhelp@lists.uoregon.edu, 346-4412) with any questions you may have about your mail connection method.

Ultimately we hope to deliver a long-term solution to Darkwing slowdowns through hardware upgrades. Until then, we sincerely appreciate your help in keeping the shared systems usable for everyone.