📊 Haskell dependencies build times profiler
dr-cabal
is a CLI tool for profiling Haskell dependencies build times.
ℹ️ DISCLAIMER: This project is developed and maintained in free time by volunteers. The development may continue for decades or may stop tomorrow. You can use GitHub Sponsorship to support the development of this project.
dr-cabal
is a CLI tool written in Haskell and can be installed
either from Hackage or from this repository.
To start using dr-cabal
, make sure you have the required version of
cabal-install
(a Haskell build tool) and GHC (a Haskell compiler)
installed:
To install the latest version of dr-cabal
from
Hackage,
follow these steps:
Update Hackage index:
cabal update
Build dr-cabal
from Hackage and copy the resulting executable
into the desired location (e.g. $HOME/.local/bin
):
cabal install dr-cabal \
--install-method=copy \
--overwrite-policy=always \
--installdir=$HOME/.local/bin
ℹ️ NOTE: Make sure the
$HOME/.local/bin
directory or the directory of your choice is listed in$PATH
.
To build the latest version of dr-cabal
from sources,
follow these steps:
Clone this repository:
git clone https://github.com/chshersh/dr-cabal.git
cd dr-cabal
Build the package:
cabal build
Copy executable to the desired location:
cp $(cabal list-bin exe:dr-cabal) ~/.local/bin/dr-cabal
ℹ️ NOTE: Make sure the
~/.local/bin
directory or the directory of your choice is listed in$PATH
.
Run the following command to view interactive profiling report:
cabal --store-dir=$(mktemp -d) build --dependencies-only all | dr-cabal profile
This section explains the above command:
dr-cabal
watches the output of the cabal build
command to
produce the profiling report. Step into the directory of the
Haskell project you want to profile and pipe the output of
cabal build
to dr-cabal profile
.dr-cabal
can profile only dependencies. So you can
pass the --dependencies-only
to avoid extra wait.cabal
caches built dependencies. You can specify a custom
directory for storing build artifacts using the --store-dir
flag
to build the dependencies anew.$(mktemp -d)
command generates a temporary directory so you
can run the build time profiler in an isolated location.⚠️ WARNING: To get meaningful results, including downloading of packages, the
dr-cabal watch
command needs to be run when none of the dependencies are build (i.e. with cold cabal cache). If you've already build you project, including dependencies, you can purge global Cabal cache using the following command:rm -rf ~/.cabal
ℹ️ In this section, a more verbose
cabal-install
command from "Quick start guide" is replaced with shortercabal build
.
dr-cabal
supports profiling of documentation as well, you only need
to pass relevant flags to cabal build
:
cabal build --enable-documentation --haddock-all | dr-cabal profile
To cache the profiling results in JSON (and avoid building the project
again), use the --output
flag:
cabal build | dr-cabal profile --output=my_file.json
Once you successfully produced a JSON file with all the recorded steps, run the following command to pretty-print the profiling output:
⚠️ WARNING: For better results, make your terminal full-screen.
dr-cabal profile --input=my_file.json
You'll see the output like on the image below: