[darcs-devel] my problems with tests that run ssh/curl

[Ganesh Sittampalam]

On 16/07/2020 10:15, Ben Franksen wrote:

> another thing that came to my mind just now: doesn't Windows nowadays
> come with a "native" version of bash (as part of the WSL aka Windows
> Subsystem for Linux)? If we could use that instead of cygwin, perhaps
> all your Windows test problems will go away?

I've played with it before, but it's quite unnative - it's more like
Docker-lite than something that is genuinely integrated with the Windows
ecosystem. So in particular I'm not sure that it would test what our
users would actually be doing when using darcs outside WSL. It might be
time to take another look, but that'll of course take up more time
itself :-)

> Don't you think we could at least try and debug this to find out *what*
> makes it so slow in Windows? It could be anything, really, but my gut
> feeling tells me it has to do with executing the 'bash test' command.

It's fairly well-known that Windows process creation is very slow
compared to Linux, so scripts that rely on cheap composition of small
utilities pay a huge performance penalty. I'm less sure why things
(probably) got a lot slower for me more recently. I should probably do
some timing tests after rebooting to clear out the spyware, and/or try
another computer to see if it behaves any differently.

Ganesh