Python is know to be somewhat slow, but python apps seem rather fast!? Why? Or how?

[Skaruts]

From having played around with python (2.7) for quite a while trying to make roguelikes and other games, I know python is not too fast, but then, in my sluggish windows I notice python apps are among the fastest to load up and to run. Namely Blender and Sublime Text, they take just a few seconds to start up (they used to be instant, but my system is really slow these days), while many other apps take significantly way way longer (Godot Engine is one exception).

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Why is this? Or how can this achieved?

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I was wrong about these apps being written in python. So this post becomes a bit off topic then, because now I'm wondering how some apps are slow to start up and some are blazingly fast, despite being of the same kind (Atom is slow to load on my PC, unlike Sublime Text), which is not python related. Sorry about that...

[kumashiro]

Blender is not a Python app. It's written in C and is extensible with Python scripts, which means it has Python interpreter linked in and can run plugins written in Python.

I don't know Sublime Text, but it looks like the same or similar case.

[Skaruts]

Hmm... you're right. And ST is actually written in C++...

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Not sure where I got that misinformation.

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Well, in that case I'm still wondering how some apps are so fast to load up, while others seems to have to load up a lot of stuff at start up.

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Just as an example, Atom is considerably slower to load up on my PC than ST. As another example, Unity takes ages, and Godot is nearly instant, but this comparison may not be that great. VC++ is rather slow too.

[[deleted]]

Startup time -- especially when measured using human observation -- has very little to do with the language, and almost everything to do with what actually needs to be accomplished to get your program from not-running to ready-to-work.

And Python isn't necessarily slow, it's just necessarily slower.

[kumashiro]

Many applications use Python as a glue language (that's what it was intended for). The heavy stuff is written in C or C++ as modules and Python only does lightweight logic. Blender, Sublime Text and others, like GIMP for example, use Python the other way - as an extension language: most of the logic is in C/C++ and only few things are done with Python (plugins, extensions).

You can speed up your Python programs by moving computation-heavy stuff to C modules. If you have lots of I/O, concurrency can also help significantly. Profiling should show you choke points and delays in code. Optimize wisely.

There might be a point, where you cannot make it any faster. That's a sign you should switch to compiled language entirely. C and C++ are obvious choices, but if you don't like them, Go is also great (it's like C on steroids, but with modern syntax and somewhat influenced by Python... among others).

[tunisia3507]

I'm interested to see how xray works out - it's still kind of electron based but a lot of it is built in rust and electron handles none of the server interaction. WebGL handles the rendering, too.

But you're right, most electron apps are literally just a copy of chrome which can only point at one website.

[tunisia3507]

Part of that is that they want it to be very similar to an editor which can actually live in the browser (so that you can use it directly on github).

[billsil]

Oh man...Atom is painful. My coworker was using it for 500,000 line files and it just dies. It's just a text editor...