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Comment by truth_seeker | Hacker News Reader

Only if they are highly I/O bound.

For example, implementing tcp/http/udp proxy servers. Static file servers too can benefit greatly.

Based on an exchange in the PR, it sounds like they have to be specifically bound on file I/O to see an improvement, not network I/O.

> is this PR just for files or also for network operations?

> Just file operations for now.

Ouch ! I missed that comment.

Not sure, why they ignored socket, it would be have been great addition to NodeJS/Python stack. Let's hope they make it happen in near future release schedule.

io_uring was made primarily for filesystem operations and is most optimized for that use case. Other file descriptor types have to be explicitly handled by the kernel side of the io_uring implementation, and while network calls are among those that have been, they still all require different handling in some cases.

Nit: Syscall bound, not necessarily I/O bound.

Both, because it allows async file I/O.

Your application must feel I/O bound. But in reality it must be syscall bound in order for io_uring to make any noticeable improvement.

In other words: if your application is already writing/reading at the max speed the hardware its on allows, you will see no improvement from this. That application is truly I/O bound.

An application that feels I/O bound will be doing lots and lots of little reads and writes and achieving low hardware utilization. That application is syscall bound rather than I/O bound, and io_uring will help tremendously.

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