> The > sendmail virtual machine has 2 virtual processors. I was thinking to > increase to 4 to avoid some processor contention but I do not > know so much > about it.
Don't. sendmail is an I/O intensive application, not processor intensive. You'll get more benefit from setting up a number of small instances and distributing the load with LVS or a external layer 4 switch than giving one instance more horsepower. Also, consider converting /var to a software RAID-5 filesystem or LVM to get more spindles into the act. If you're seeing processor contention, work on splitting the functions up. sendmail and the POP/IMAP daemons use resources very differently, and they don't play nicely together. Another reason you might want to switch to Exim is better support for maildir format mailboxes. If you're using the classic sendmail with Unix mbox support, you're spending a lot of unnecessary system time in seeks to append to mailbox files. maildir just creates a new small file and moves on. Much, MUCH faster, and less resource intensive, and a lot friendlier for shared mail spool systems. > I know that 1.5 GB memory is too much. It will take a while > to split the > workload in two different machines. I have 4000 email users > that have to > change their configurations. They point to the same server > (same hostname). > It is not common to see this type of configuration, both > services on the > same machine... Actually, you can do it very quickly. Build a new POP/IMAP server instance and get it running the way you like it. Then, on the original server, use the port forwarding capability in the firewall code to redirect incoming connections for the POP and IMAP ports to the new POP/IMAP server. Presto -- separated function. > The best thing to do now is to reduce the machine virtual > memory (I have the > free -m statistics) and upgrade the sendmail. I'll do those > things first and > see what happen. A good start. For this environment, think horizontal scaling. It's often better to have many small machines than few big ones. -- db ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
