Re: Threads across programming languages

On 5/1/2024 1:34 PM, Lawrence D'Oliveiro wrote:

On Wed, 1 May 2024 10:59:16 +0200, Bonita Montero wrote:
 

Am 01.05.2024 um 10:53 schrieb Lawrence D'Oliveiro:
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On Wed, 1 May 2024 10:13:03 +0200, Bonita Montero wrote:
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Am 01.05.2024 um 09:10 schrieb Lawrence D'Oliveiro:
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On Wed, 1 May 2024 06:54:13 +0200, Bonita Montero wrote:
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Boost.ASIO does that all for you with a convenient interface.
If enabled it even uses io_uring or the Windows' pendant.

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How many languages does it support?

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Just C++ ...

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Not much use, then.

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System-level programming is mostly made with C++.

 No, it is actually mostly C, with Rust making inroads these days.
 And you don’t have to be doing “system-level” programming to be needing
event-driven paradigms.
 

But functions and classes are not first-class objects in C++, ...

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Of course, since C++11.

 No they aren’t. You cannot easily define a C++ function that returns a
general function or class as a result, just for example.
 

You cannot define function factories and class factories, like you can
in Python.

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Python is nothing for me since it is extremely slow.

 Remember, we’re talking about maximizing I/O throughput here, so CPU is
not the bottleneck.

It can be if your thread synchronization scheme is sub par. I have actually seen code where an IOCP completion thread locks a global mutex. Something like this pseudo-code:
_________________
for (;;)
{
    iocp_overlapped& p = GQCS(INFINITE);
    lock_mutex(global);
    // process event...
    unlock_mutex(global);
}
_________________
This is really BAD! It will create a rather massive bottleneck under times of heavy load... Also, it creates a nasty condition where things can become deadlocked if processing the overlapped completion calls into unknown user code to do some work. I have had to debug some others code like this before. Not exactly fun...