Lexmark C792 Administrator's Manual page 22

Installing Lexmark Document Distributor
Consider the following example:
• Each server in your system can process 3000 jobs per hour using the solution.
•
There is capacity for 300 printers in your system.
•
Each printer in your system averages 100 jobs per day.
Perform the following calculations:
1
Determine the system‑wide hourly job rate:
(300 printers) x (100 daily jobs/printer) / (8 hours/day) = 3750 jobs/hour
2
Determine the peak demand:
2 x (3750 jobs/hour) = 7500 jobs/hour
3
Determine the minimum number of servers:
(7500 jobs/hour) / (3000 jobs/hour) = 2.5
Rounding up, the system should include three servers to reliably handle the peak load for a solution with average
execution time below 30 seconds.
The single‑server throughput for a solution must be determined by the solution developer, though the following typical
throughputs on a server with the recommended hardware may help determine a rough estimate:
Solution processing load Functions used
Typical
Heavy
Very heavy (OCR)
Note: Using less than the recommended RAM significantly reduces throughput. For example, a dual‑processor server
with only 2GB of RAM can process only 600–800 jobs/hour when using a "heavy" solution.
For more information, see the Lexmark Document Distributor SDK Guide.
Concurrency
Each server that meets recommended requirements can process 30 concurrent jobs from clients. The following formula
determines the number of servers necessary to meet concurrency requirements:
(minimum number of servers) = (number of printers expected to submit jobs near the same time) / 30
For example, assume that 1/3 of the 300 printers in the last example might be active at the same time:
100 / 30 = 3.33
Rounding up, the system should include four servers to allow for 100 active printers for a solution with average execution
time below 30 seconds.
•
Some image processing
•
Printing
•
Extensive image processing
•
Bar codes
•
External processes
• Small to medium Document Producer (e-forms) jobs
•
OCR
•
Large Document Producer (e-forms) jobs
Average single‑server throughput
6000–8000 jobs per hour
2000–3000 jobs per hour
100–200 jobs per hour
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