criterion performance measurements
overview
want to understand this report?
testTerms/0
| lower bound | estimate | upper bound | |
|---|---|---|---|
| OLS regression | xxx | xxx | xxx |
| R² goodness-of-fit | xxx | xxx | xxx |
| Mean execution time | 3.9711414917326017e-7 | 3.9884804768065843e-7 | 4.014449211568164e-7 |
| Standard deviation | 5.388239779420349e-9 | 6.866861560803509e-9 | 9.062754899572569e-9 |
Outlying measurements have moderate (0.1987136571266061%) effect on estimated standard deviation.
testTerms/1
| lower bound | estimate | upper bound | |
|---|---|---|---|
| OLS regression | xxx | xxx | xxx |
| R² goodness-of-fit | xxx | xxx | xxx |
| Mean execution time | 3.834569334128308e-6 | 3.845986689574006e-6 | 3.862174477210126e-6 |
| Standard deviation | 3.767548765189185e-8 | 4.48914869657769e-8 | 5.4178975797734935e-8 |
Outlying measurements have slight (8.224355804737946e-2%) effect on estimated standard deviation.
testTerms/2
| lower bound | estimate | upper bound | |
|---|---|---|---|
| OLS regression | xxx | xxx | xxx |
| R² goodness-of-fit | xxx | xxx | xxx |
| Mean execution time | 3.951507748863946e-5 | 3.959364128819829e-5 | 3.967573606868778e-5 |
| Standard deviation | 2.0427277620001873e-7 | 2.6592009266049883e-7 | 3.5927073205462814e-7 |
Outlying measurements have no (7.298875432525939e-3%) effect on estimated standard deviation.
testTerms/3
| lower bound | estimate | upper bound | |
|---|---|---|---|
| OLS regression | xxx | xxx | xxx |
| R² goodness-of-fit | xxx | xxx | xxx |
| Mean execution time | 4.022786282979502e-4 | 4.028169179971992e-4 | 4.032538131263678e-4 |
| Standard deviation | 1.3557550160898703e-6 | 1.6626617603816654e-6 | 2.0335707248978515e-6 |
Outlying measurements have slight (1.1109708370155017e-2%) effect on estimated standard deviation.
understanding this report
In this report, each function benchmarked by criterion is assigned a section of its own. The charts in each section are active; if you hover your mouse over data points and annotations, you will see more details.
- The chart on the left is a kernel density estimate (also known as a KDE) of time measurements. This graphs the probability of any given time measurement occurring. A spike indicates that a measurement of a particular time occurred; its height indicates how often that measurement was repeated.
- The chart on the right is the raw data from which the kernel density estimate is built. The x axis indicates the number of loop iterations, while the y axis shows measured execution time for the given number of loop iterations. The line behind the values is the linear regression prediction of execution time for a given number of iterations. Ideally, all measurements will be on (or very near) this line.
Under the charts is a small table. The first two rows are the results of a linear regression run on the measurements displayed in the right-hand chart.
- OLS regression indicates the time estimated for a single loop iteration using an ordinary least-squares regression model. This number is more accurate than the mean estimate below it, as it more effectively eliminates measurement overhead and other constant factors.
- R² goodness-of-fit is a measure of how accurately the linear regression model fits the observed measurements. If the measurements are not too noisy, R² should lie between 0.99 and 1, indicating an excellent fit. If the number is below 0.99, something is confounding the accuracy of the linear model.
- Mean execution time and standard deviation are statistics calculated from execution time divided by number of iterations.
We use a statistical technique called the bootstrap to provide confidence intervals on our estimates. The bootstrap-derived upper and lower bounds on estimates let you see how accurate we believe those estimates to be. (Hover the mouse over the table headers to see the confidence levels.)
A noisy benchmarking environment can cause some or many measurements to fall far from the mean. These outlying measurements can have a significant inflationary effect on the estimate of the standard deviation. We calculate and display an estimate of the extent to which the standard deviation has been inflated by outliers.