While migrating some jobs from Travis and Appveyor to GHA, I found that windows jobs on GHA are consistently x3.5 times slower. This is surprising, because GNU/Linux and macOS jobs are about the same time. For example:
I think it might be related to https://github.community/t5/GitHub-Actions/Windows-container-I-O-performance-is-slower-than-on-a-linux/m-p/38376#M3325, since the tests above are quite I/O intensive.
This might be a problem for many projects, specially because Actions are priced per minute.