> > Queueing under load is bad advice, as it makes things worse. Mail servers > > are usually limited by I/O. Immediate delivery delivers from page cache.
>
> However delivery requires many more fsyncs than just queueing.
Yes, it causes more work in the short term, but less in total (long term).
That's why it is a good advice for short peaks, and only then.
> > Put it differently: What would break if geometric retry intervals would
> > use the computed earliest retry time as interval for a random number?
>
> Probably nothing :-)
