Strange, strange performance impact on Windows

[Inversion-des]

After some investigation in my app I found that Pry session has a significant impact on the performance of requests to MongoDB.

I have prepared a test set to show this — https://gist.github.com/Inversion-des/18cc3a25f01450f98cbfdd66dc0d735d
Here are my results — https://gist.github.com/Inversion-des/40fa039a13f9f5ccd5b5f96c62bcfb54.

As you can see, the active Pry session makes some requests 3-10 times slower.
Is it ok, or I'm doing something wrong?

And how can we explain that after closing the Pry session some requests become 3-6 times faster??? And it is not some random result, it is a stable effect.

I checked that only "require 'pry'" has no effect, you need to start and exit the session.

I checked that there are no such effects on Linux.

Environment:

• Windows 10
• Ruby v2.5.5.157 (2019-03-15) [x64-mingw32]
• Pry: v0.12.2
• Mongo: v2.9.0.rc0, BSON: v4.5.0

[andrehjr]

Hi, I can't think of a reason why starting a pry session would make that happen. I've run your script on macos and the numbers seem ok.

I would also test calling binding.irb to narrow down if the issue is really pry, or something else. Something like https://github.com/jhawthorn/vernier would maybe help in finding out where the time is being spent.

I don't have a windows machine available right now. So, as this is an old issue, If anyone can help debug, or can still reproduce, I can open this again.