sendmail, 4th Edition

QueueLA

On high load, queue only All versions

When the load average on a machine (the average number of processes in the queue run over the past minute) becomes too high, sendmail can compensate in three different ways:

• This QueueLA option determines the load at which sendmail will begin to queue messages rather than delivering them, and the load at which scheduled runs will be skipped.

• The RefuseLA option (RefuseLA on page 1078) determines the load at which sendmail will begin to refuse connections rather than accepting them.

• The DelayLA option (DelayLA on page 1002) determines the load at which sendmail will begin to delay replies to SMTP commands.

The QueueLA option specifies the load above which sendmail queues messages rather than delivering them. The QueueLA and QueueFactor options interact to determine this cutoff; they are both covered under the QueueFactor option (QueueFactor on page 1071).

The forms of the QueueLA option are as follows:

O QueueLA=load                ← configuration file (V8.7 and later)
-OQueueLA=load                ← command line (V8.7 and later)
define(`confQUEUE_LA',load)   ← mc configuration (V8.7 and later)
Oxload                        ← configuration file (deprecated)
-oxload                       ← command line (deprecated)

The optional argument load, of type numeric, defaults to zero if it is missing. If the entire QueueLA option is missing, the default value given to load is eight times the number of CPU processors. The default for the mc technique is to omit this option. On newer, faster machines a higher setting might be more ...