Pedro Arantes
HomeBlogMe

Cumulative Flow Diagram (CFD)

The cumulative flow diagram (CFD) is a helpful tool for managing queues.
#cumulative-flow-diagram
Zettelkasten, December 1st, 2021.

Notes

  • The cumulative flow diagram (CFD) is a helpful tool for managing queues.

  • The diagram uses:

    • Time as its horizontal axis;
    • Cumulative quantity as its vertical axis;
    • Cumulative arrivals at a process as one variable;
    • Cumulative departure as a second variable.
  • The vertical distance between the arrival line and the departure line is work that has arrived but not yet departed, the size of the queue at a time.

  • The horizontal distance between the lines tells the cycle time through the process for an item of work.

  • The total area between these two lines tells the size of the queue.

  • The slope of the arrival line tells the arrival rate of the queue.

  • The slope of the departure line tells the capacity of the process of emptying the queue.

Cumulative Flow Diagram (CFD)

Cumulative Flow Diagram (CFD)

References

Flow. Chapter 3 - Managing Queues
RecommendationsDo you want to see all posts instead?
At High Utilization Levels, Queues Grow Much Faster than They Can Shrink