Benchmarks

pvlib includes a small number of performance benchmarking tests. These tests are run using airspeed velocity (ASV).

The basic structure of the tests and how to run them is described below. We refer readers to the ASV documentation for more details. The AstroPy documentation may also be helpful.

The test configuration is described in asv.conf.json. The performance tests are located in the benchmarks directory.

Comparing timings

Note that, unlike pytest, the asv tests require changes to be committed to git before they can be tested. The run command takes a positional argument to describe the range of git commits or branches to be tested. For example, if your feature branch is named feature, a useful asv run may be (from the same directory as asv.conf.json):

$ asv run main..feature

This will generate timings for every commit between the two specified revisions. If you only care about certain commits, you can run them by their git hashes directly like this:

$ asv run e42f8d24^!

Note: depending on what shell they use, Windows users may need to use double-carets:

$ asv run e42f8d24^^!

You can then compare the timing results of two commits:

$ asv compare 0ff98b62 e42f8d24

All benchmarks:

       before           after         ratio
     [0ff98b62]       [e42f8d24]
     <asv_setup~1>       <asv_setup>
+      3.90±0.6ms         31.3±5ms     8.03  irradiance.Irradiance.time_aoi
       3.12±0.4ms       2.94±0.2ms     0.94  irradiance.Irradiance.time_aoi_projection
          256±9ms         267±10ms     1.05  irradiance.Irradiance.time_dirindex

The ratio column shows the ratio of after / before timings. For this example, the aoi function was slowed down on purpose to demonstrate the comparison.

Generating an HTML report

asv can generate a collection of interactive plots of benchmark timings across a commit history. First, generate timings for a series of commits, like:

$ asv run v0.6.0..v0.8.0

Next, generate the HTML report:

$ asv publish

Finally, start a http server to view the test results:

$ asv preview

Nightly benchmarking

The benchmarks are run nightly for new commits to pvlib-python/main.

Timing results: https://pvlib.github.io/pvlib-benchmarks/
Information on the process: https://github.com/pvlib/pvlib-benchmarks