Knowledge base

Throughput peaks

Top/Hour and Top/Minute
The best the node has shown

The highest values per hour and per minute — recipients, messages, kilobytes.

A peak answers the question “what the node is capable of”, not “what it is doing”. Planning load by it is dangerous: the peak was reached under its own conditions, and they cannot be repeated every hour.

The Hub also computes peaks itself, from its own time series — over the chosen window, not the one the engine set.

The main trap is taking a snapshot for a history. The metric describes the moment of polling. Everything that happened between two measurements and managed to end will not get into either of them. For events there is accounting, for state — these numbers.
What the Hub does. It shows it live: the node monitor displays the peaks per hour and per minute from the status snapshot, but the poll does not put them into the time series.

The Hub also computes peaks itself, from its own time series — over the chosen window, not the one the engine set.

Recommended values

What to compare with:

Value Compared with
current value the usual one for this node, not the neighboring one
peak the ceiling, if there is one
growth the growth rate, not the absolute number

Fleet nodes are not directly comparable: they have different hardware, different addresses and a different mix of receivers. It makes sense to compare a node with itself over time.

The comparison advice is ours. From the manual here come the metric’s composition and its units of measurement.
Example configuration
# the metric comes in the status snapshot
curl -s "http://127.0.0.1:8080/status?format=json"pmta show status
The highlighted line returns the snapshot as a structure — that is how the Hub’s polling reads it. The line below prints the same thing in the console.
yellow — — directive names, blue — blocks. They are highlighted the same way in the text of the card.
Compatibility
PowerMTA 6.0
described in the manual of this version · platform: any
The vendor does not state the first version for every directive — there is no note here. The name also appears in the 5.0 edition of the manual.
How to check on the node
The metric is viewed together with the neighboring ones — on its own any number means little:
pmta show status
pmta show queues --sort=rcpt --maxitems=20
The first prints all node metrics at once. The second breaks down by queue what the first gives as one number — and that is usually where you can see which queue made it up.
In the Hub
Cost of a mistake
safe: a wrong value breaks nothing
Scenarios
Capacity planning