When will MailScanner + postfix actually say "421 too much load"

[Ronny T. Lampert]

>> topic says it all: when will a MailScanner + postfix actually go into 
>> the "Too much load" situation?
>>
>> Will MailScanner actually affect postfix's decision to go 421?
> MailScanner is not involved with the SMTP transaction at all, so this is 
> nothing to do with MailScanner, it's all down to Postfix.

That's what I was suspecting; but I know that e.g. sendmail is doing 
funny calculation about when to go 421 and it does by using the loadavg 
and some overall process stats.

Thanks!
Ronny