Here is a 2 years old article, which explains why the architec | Bortlog

Here is a 2 years old article, which explains why the architecture of all modern operating systems is obsolete. The advent of new hardware and very high-speed network and disk interfaces, makes the strategy of running the kernel on all CPU cores and work with interfaces via system calls, disadvantageous due to the large number of context switches and the presence of shared memory.
To write really high-performant software, people are now doing kernel bypass, using eBPF or XDP.
And this is just one of the 5 points of criticism listed by the article authors.

The authors propose a new operating system architecture which they call parakernel. And this architecture will be as complementary as possible to all sorts of thread-per-core frameworks such as Seastar (http://seastar.io). Parakernel allocates all the necessary DRAM resources, network RX / TX queues, and disk NVMe queues when starting or initializing the process and guarantees their isolation and unique ownership by the process. It is proposed to implement network protocols in user space. Discard almost all POSIX APIs, especially various blocking operations, get rid of virtual address space, or leave it as a security feature, but ensure that the OS will make page replacements, swap memory pages, etc.
It turns out that the in such architecture kernel will only deal with resource allocation, handle process failures, and work as an adapter in case we run on some legacy hardware that does not support resource allocation at the driver or hardware level.

In short, it is a really cool article, and if you are interested in details, you can come here: https://penberg.org/parakernel-hotos19.pdf