plot,USL-method {usl} | R Documentation |
Plot the scalability function from a USL model
Description
Create a line plot for the scalability functionh of a Universal Scalability Law model.
Usage
## S4 method for signature 'USL'
plot(
x,
from = NULL,
to = NULL,
xlab = NULL,
ylab = NULL,
bounds = FALSE,
alpha,
beta,
...
)
Arguments
x |
The USL object to plot. |
from |
The start of the range over which the scalability function will be plotted. |
to |
The end of the range over which the scalability function will be plotted. |
xlab |
A title for the x axis: see |
ylab |
A title for the y axis: see |
bounds |
Add the bounds of scalability to the plot. This always
includes the linear scalability bound for low loads. If the contention
coefficient |
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. |
... |
Other graphical parameters passed to plot
(see |
Details
plot
creates a plot of the scalability function for the model
represented by the argument x
.
If from
is not specified then the range starts at the minimum value
given to define the model. An unspecified value for to
will lead
to plot ending at the maximum value from the model. For add = TRUE
the defaults are taken from the limits of the previous plot.
xlab
and ylab
can be used to set the axis titles. The defaults
are the names of the regressor and response variables used in the model.
If the parameter bounds
is set to TRUE
then the plot also
shows dotted lines for the theoretical bounds of scalability. These are
the linear scalability for small loads and the Amdahl asymptote for the
limit of scalability as load approaches infinity.
The parameters alpha
or 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.
See Also
Examples
require(usl)
data(specsdm91)
## Plot result from USL model for demo dataset
plot(usl(throughput ~ load, specsdm91), bounds = TRUE, ylim = c(0, 3500))