[TBD]Understanding FreeBSD kernel

M:N Threading model

There are two implementations of threading in FreeBSD. The M:N library divides the work between kernel space and userspace. Thread is an entity that gets scheduled in the kernel but it can represent various number of userspace threads. M userspace threads get mapped to N kernel threads thus saving resources while keeping the ability to exploit multiprocessor parallelism.

Useful link: https://www.freebsd.org/doc/en_US.ISO8859-1/articles/linux-emulation/inside.html

Notes

• • Its called a Unix like system

  • Most portable OS

    • Due to C based implementation

    • Due to its design

About BSD

The distributions from Berkeley were the first UNIX-based systems to introduce many important features including the following:

• Demand-paged virtual-memory support

• Automatic configuration of the hardware and I/O system

• A fast and recoverable filesystem

• The socket-based interprocess-communication (IPC) primitives • The reference implementation of TCP/IP

Reference

https://en.wikipedia.org/wiki/Marshall_Kirk_McKusick