Reference Guide

mechanism behaves to that (pink line), slowing down the reaction time as the load increases. After the 8th
minute, the peak is ended, and the load is back to approximately 4 APJs/min.
The pink curve represents the number of messages being queued (which indicates control messages needed
to process the job), and how quickly HP ePrint Enterprise can consume them and get jobs printed. Notice that
this number still grows a couple minute after the submission peak ends, as there is some latency between
submission of the job and the queuing of messages for processing. After the 10th minute, HP ePrint
Enterprise is capable of starting to consume messages more quickly than they are created, considering the
base load of 4 APJs/min.
With the default timeout for queued messages set at 10 minutes, all jobs will eventually be handled with
success. However, it takes HP ePrint Enterprise about 1 hour to recover from that, and reach about the same
number of queued messages observed before the peak.
4.4.2 Without base load
This scenario was analyzed based on the assumption that a typical system usage may have absolutely no
base load (i.e. no initial activity or queued job requests), on top of which 40 APJ’s can be sent to 10 different
printers, all at once. The processing of each printer is serialized, so 10 printers mean 10 parallel processes –
which explain the 10 simultaneous APJ’s top of the blue line. If more printers were involved, the blue line
would top at this number.
In this scenario, HP ePrint Enterprise was able to instantly accept 40 APJ’s, taking approximately 10 minutes
to finish processing them.
Instant load: system is idle, 40 APJ’s are sent to 10 different printers.
Section 4.4 Peak analysis 15