[frozenport]

Linux system internal are ugly, there is little progress on static driver verification, resource management heuristics are poorly tuned, and the kernel network stack is so bad, you can make a living selling your own user space version. Linux has a lot of very real problems.

[sargun]

I'm really curious as to where you find the kernel's network stack problematic? Can you explain that in more detail?

Also, what issues do you have with the scheduler?

[frozenport]

https://blog.cloudflare.com/kernel-bypass/

For an example among many. Basically network data should magically appear in bulk, whereas in Linux it's almost one packet at a time.

As you move to 10G, thus start to eat a lot of cpu.

[sargun]

Since that article was published, things have changed a little bit. At least for the filtering use case they talked about in the blog, XDP (https://www.iovisor.org/technology/xdp) has come about, which is an in-kernel mechanism by which to filter at wire speed.

I don't disagree that there are many examples, but it's hard to solve them unless people give specifics.

[angry_octet]

Not really a problem for mobile... For HPC there have been user mode and offload tweaks since forever. The fact that none of the hardware or task specific techniques can replace the traditional BSD sockets stack is because writing that in general is a ton of work... Work which G would have to do ^10 to replace Linux in an android context.

[frozenport]

Wasted cycles are directly proportional to power consumption.

[bitmapbrother]

This may be applicable:

Scheduling for Android devices

https://lwn.net/Articles/706374/