1.3.0

A big swath of bug fixes and improvements. The highlights certainly are fixes and conveniences around saved benchmarks and loading them again via the new Benchee.report/1. The other big one is saving a lot of memory (and time!) when processing big inputs. Sadly the latter comes with some breaking changes for plugins, but they are well justified and shouldn't actually affect any plugin in practice.

There's also a known issue for elixir 1.14.0 to 1.16.0-rc.0 - read up about it.

Features (User Facing)

• System information now includes whether or not the JIT is enabled (erlang docs).
• Benchee now let's you know when it's calculating statistics or running the formatters. Helps when you wonder what's taking so long or blows up memory.
• Benchee.report/1 introduced if you just want to load saved benchmarks and report on them (---> run formatters).
• Configuration times will now be displayed in a more human friendly format (1 min 12 s vs. 1.2 min). Thanks to @drobnyd.

Bugfixes (User Facing)

• Memory usage should be massively reduced when dealing with larger sets of data in inputs or benchmarking functions. They were needlessly sent to processes calculating statistics or formatters which could lead to memory blowing up.
• Similarly, inputs and benchmarking functions will no longer be saved when using the :save option, this makes it immensely faster and depending on the size of the data a lot slower (I have an example with a factor 200x for the size). The side effect of this is that you also can't use :load and run the benchmarks saved again from just the file, this was never an intended use case though (as loading happens after benchmarking by default). You also still should have the benchmarking script so it's also not needed.
• Fix a bug where relative statistics would always rely on the inputs provided in the config, which can break when you load saved benchmarks but don't specify the inputs again.

Breaking Changes (Plugins)

Woopsie, didn't wanna do any of these in 1.x, sorry but there's good reason :( However, counting them as bugs.

• Formatters have lost access to benchmarking functions and the inputs, this is to enable huge memory and run time savings when using a lot of data. I also believe they should not be needed for formatters, please get in touch if this is a problem so we can work it out. In detail this means:
  • Each Benchee.Scenario struct in a formatter will have :function and :input set to nil
  • The inputs list in Configuration retains the input names, but the values will be set to :scrubbed_see_1_3_0_changelog. It may be completely scrubbed in the future, use the newly introduced input_names instead if you need easy access to all the input names at once.
  • Technically speaking formatters haven't generally lost access, only if they are processed in parallel - so not if it's the only formatter or if it's used via a function (formatters: [fn suite -> MyFormatter.output(suite) end]. Still, should not be used or relied upon.

Features (Plugins)

• jit_enabled? is exposed as part of the suite.system struct
• Yes, Benchee.System is now a struct so feel easier about relying on the fields
• Configuration now has an input_names key that holds the name of all inputs, for the reasoning, see above.
• The more human friendly formats are accessible via Format.format_human/2 or Duration.format_human/1 (& friends)