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A comment on FreeBSD 10.3. Parent comment

Re:FreeBSD 10.3 by akerro on Monday April 04, 2016 @03:26AM (#11420019)
>The Linux® compatibility layer has been substantially improved and now is capable of running 64-bit applications on amd64 (x86_64), 1:1 threading

What does 1:1 threading mean?

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Re:FreeBSD 10.3 by kev009 on Monday April 04, 2016 @03:32AM (#11420047)
There are at least three theoretical implementations of userland threads in an Operating System:

* 1:1, where each userland thread maps directly to a kernel thread

* 1:N, where several userland threads map directly to one kernel thread

* M:N, where the kernel maintains a pool of threads and dispatches userland threads to them

History has shown that 1:1 threading has the best trade offs. It's worth more independent research if you are interested in Operating Systems.

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Re:FreeBSD 10.3 by akerro on Monday April 04, 2016 @04:06AM (#11420163)
Thanks
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Re:FreeBSD 10.3 by anthk on Monday April 04, 2016 @08:04AM (#11421179)
That's reminds me of database record relations.
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Re:FreeBSD 10.3 by akerro on Monday April 04, 2016 @10:26AM (#11422083)
Or just re-use of basic structures ;)
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Re:FreeBSD 10.3 by xtf on Monday April 04, 2016 @03:31AM (#11420043)
https://en.wikipedia.org/wiki/Thread_%28computing%29#1:1_.28...: 1:1 (kernel-level threading)

Threads created by the user in a 1:1 correspondence with schedulable entities in the kernel[10] are the simplest possible threading implementation. OS/2 and Win32 used this approach from the start, while on Linux the usual C library implements this approach (via the NPTL or older LinuxThreads). This approach is also used by Solaris, NetBSD, FreeBSD, OS X, and iOS.

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Re:FreeBSD 10.3 by mkup on Monday April 04, 2016 @05:42AM (#11420491)
It's also worth noting that FreeBSD used to rely on M:N threading model (via libkse) then switched to 1:1 threading model (via libthr).
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Re:FreeBSD 10.3 by jdub on Monday April 04, 2016 @05:43AM (#11420496)
Though LinuxThreads was M:N, and Solaris migrated to 1:1 relatively recently too (as did others).
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Re:FreeBSD 10.3 by the_why_of_y on Monday April 04, 2016 @02:37PM (#11424224)
No, LinuxThreads was 1:1. Maybe you are thinking of IBM's NGPT proposal?

http://www.onlamp.com/pub/a/onlamp/2002/11/07/linux_threads....

"Relatively recently" would be Solaris 8, in 2000.

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