I have also thought about that... but if you have a look at Qmail's website (http://www.qmail.org) then you'll see that a number of extremely large mail companies (hotmail for one) uses qmail for... get this... outgoing mail. They could've easily chosen sendmail, postfix (maybe it wasn't around when they designed their systems), zmailer, etc. but those chose qmail.
Why would that be? I'm not sure about exim (haven't used it before) but qmail can open (after patching) over 500 or even 1000 concurrent outgoing connections. I've patched and recompiled qmail to send 500 concurrent outgoing emails, which I thought would be plenty. Unfortunately, I haven't had the opportunity to ever see it go that high because (as Russell is suggesting) the hard disks just cannot feed mail fast enough into the system. Most I've ever seen it go was approximately 250 concurrent emails. And who said bandwidth is always the limiting factor? If only there was some simple way to spread the mail queue over 2 disks naturally (not by raid). In the /var/qmail/queue directory, sh-2.05# ls -al total 44 drwxr-xr-x 11 qmailq qmail 4096 Jun 8 09:04 . drwxr-xr-x 13 root root 4096 Jun 8 15:24 .. drwx------ 2 qmails qmail 4096 Jun 8 21:54 bounce drwx------ 25 qmails qmail 4096 Jun 8 09:04 info drwx------ 25 qmailq qmail 4096 Jun 8 09:04 intd drwx------ 25 qmails qmail 4096 Jun 8 09:04 local drwxr-x--- 2 qmailq qmail 4096 Jun 8 09:04 lock drwxr-x--- 25 qmailq qmail 4096 Jun 8 09:04 mess drwx------ 2 qmailq qmail 4096 Jun 8 21:54 pid drwx------ 25 qmails qmail 4096 Jun 8 09:04 remote drwxr-x--- 25 qmailq qmail 4096 Jun 8 09:04 todo However, as Russell also mentioned in a previous email, qmail uses inode numbers extensively for the queue, so there would be a huge headache in splitting them up as the system would be unable to cope with 2 different inodes from 2 different hard disks. :-/ Sincerely, Jason ----- Original Message ----- From: "Peter Billson" <[EMAIL PROTECTED]> To: "Jason Lim" <[EMAIL PROTECTED]> Cc: <debian-isp@lists.debian.org> Sent: Friday, June 08, 2001 8:04 PM Subject: Re: Finding the Bottleneck > > Additionally, as far as I can see, most emails get sent to the same > > moderately large list of domains (eg. aol), so the local DNS server > > would've cache them already anyway. > > This has been a long thread so forgive me if this has already been > discussed but... > If you are usually delivering multiple messages to a handful of > domains wouldn't the performance be greatly improved by using Exim or > Sendmail that is capable of delivering multiple messages per connection? > Particularly if AOL is involved since I have seen it take four or five > attempts to get a connection to their SPAM clogged mail servers. > If I understand q-mail correctly it does one message per connection > and opening/closing the connection often takes longer then transmitting > the data. > > DISCLAIMER: This post is not intended to start a religious war over > which mail transport program is best! :-) > > Pete > -- > http://www.elbnet.com > ELB Internet Services, Inc. > Web Design, Computer Consulting, Internet Hosting > > > -- > To UNSUBSCRIBE, email to [EMAIL PROTECTED] > with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED] > >
