THE NUMBERS, EXPLAINED
How to use this calculator.
Transfer and apply stages are treated as a continuously pipelined bottleneck. Constant rates ignore network variability, buffering and pauses. A zero starting backlog reports already caught up at this instant even if future rates would create a backlog.
Start with your inputs
Enter current backlog (bytes), new data generation (bytes/s), transfer capacity (bytes/s), apply capacity (bytes/s). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Current backlog (bytes) | 1000000000 |
| New data generation (bytes/s) | 1000000 |
| Transfer capacity (bytes/s) | 5000000 |
| Apply capacity (bytes/s) | 3000000 |
A worked example
With the example inputs above, bottleneck throughput (bytes/s) is 3,000,000. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Bottleneck throughput (bytes/s) | 3,000,000 |
| Net drain rate (bytes/s) | 2,000,000 |
| Catch-up time (seconds) | 500 |
| Scenario status | Converges |
How this is calculated
Bottleneck throughput (bytes/s)
The smaller of transfer and apply capacity.
Net drain rate (bytes/s)
Bottleneck throughput minus incoming generation rate.
Catch-up time (seconds)
Backlog divided by positive net drain rate. Zero backlog takes zero time; positive backlog with non-positive net rate cannot converge.
Scenario status
Describe whether the current backlog can drain under the supplied constant rates.
Symbols and units
- a
- Current backlog (bytes)
- b
- New data generation (bytes/s)
- c
- Transfer capacity (bytes/s)
- d
- Apply capacity (bytes/s)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions and limits
Transfer and apply stages are treated as a continuously pipelined bottleneck. Constant rates ignore network variability, buffering and pauses. A zero starting backlog reports already caught up at this instant even if future rates would create a backlog.
Calculations use the values you enter. Blank or invalid inputs show an error instead of silently substituting zero. Results are displayed to useful precision; calculations retain the underlying numeric precision.
Questions about this tool
What does the result tell me?
Bottleneck throughput (bytes/s); Net drain rate (bytes/s); Catch-up time (seconds); Scenario status. The result applies to the method and inputs described above. Check the units and assumptions before using it in a decision.
Why might another calculator differ?
Differences in units, rounding, timing or model definitions can produce different answers. Compare the input definitions and the method, rather than only the final number. For this tool: Transfer and apply stages are treated as a continuously pipelined bottleneck. Constant rates ignore network variability, buffering and pauses. A zero starting backlog reports already caught up at this instant even if future rates would create a backlog.
Are my inputs stored or sent to AI?
Calculations on this page happen in your browser. The separate AI question finder sends its submitted conversation to OpenAI; these calculator fields are not sent. Favourites and recent tool names are stored locally. A shared link contains the inputs you choose to include.
Further reading
OpenStax: percentages and proportions ↗
Background reading; this does not imply endorsement or independent review of SumFizz.
Review status
Software example and browser checks are recorded in our quality report. No external expert review is claimed. Created with coding assistance; calculations run as ordinary browser code.
Read the quality report →