scalability,USL-method: Scalability function of a USL model

Description

scalability is a higher order function and returns a function to calculate the scalability for the specific USL model.

Usage

# S4 method for USL
scalability(object, alpha, beta, gamma)

Value

A function with parameter x that calculates the scalability value of the specific model.

Arguments

object: A USL object.
alpha: Optional parameter to be used for evaluation instead of the parameter computed for the model.
beta: Optional parameter to be used for evaluation instead of the parameter computed for the model.
gamma: Optional parameter to be used for evaluation instead of the parameter computed for the model.

Details

The returned function can be used to calculate specific values once the model for a system has been created.

The parameters alpha and beta are useful to do a what-if analysis. Setting these parameters override the model parameters and show how the system would behave with a different contention or coherency delay parameter.

References

Neil J. Gunther. Guerrilla Capacity Planning: A Tactical Approach to Planning for Highly Scalable Applications and Services. Springer, Heidelberg, Germany, 1st edition, 2007.

Examples

Run this code

require(usl)

data(raytracer)

## Compute the scalability function
scf <- scalability(usl(throughput ~ processors, raytracer))

## Print scalability for 32 CPUs for the demo dataset
print(scf(32))

## Plot scalability for the range from 1 to 64 CPUs
plot(scf, from=1, to=64)

Run the code above in your browser using DataLab