bin: config: Provide maxstdio option for increasing I/O limit on Windows

[cosmo0920]

With default limit of I/O on Windows is somewhat small for large amount of log volume environment. I provide an option to set up this limit up to 2048.

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https://github.com/fluent/fluent-bit-docs/pull/1528

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• [ ] Backport to latest stable release.

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[edsiper]

@cosmo0920 we don't do ulimit stuff in Fluent Bit, why should we do it for Windows ? (maybe we just need to update the docs for windows users ?)

[nuclearpidgeon]

Is this limit something that can actually be changed at a system configuration level on Windows?

This is the MS doco about the setter function: https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/setmaxstdio?view=msvc-170 . It seems to be specifically something that's part of the Microsoft C runtime library (CRT).

There's some info here saying that the limit can be further stretched if you use specific Win32 calls directly rather than this C runtime library: https://stackoverflow.com/questions/870173/is-there-a-limit-on-number-of-open-files-in-windows/4276338#4276338

[cosmo0920]

@cosmo0920 we don't do ulimit stuff in Fluent Bit, why should we do it for Windows ? (maybe we just need to update the docs for windows users ?)

In Windows, we need to set up the ulimit like limit via _setmaxstdio. There is no API/mechanism without this API from C runtime.

[edsiper]

thanks folks for the context. @cosmo0920 I suggest to rename this option to windows.maxstdio

[cosmo0920]

Sure, I'll rename it from the previous one.

[cosmo0920]

I rebased off the current master and added windows. prefix on the newly introduced parameter.

[edsiper]

will merge after rebasing to avoid conflict.

[cosmo0920]

I rebased off the current master.

[edsiper]

@cosmo0920 for this one please make sure to submit documentation updates.