Re: Comments on the KSE option

On Sat, 28 Oct 2006, Scott Long wrote:

Daniel Eischen wrote:
Actually, that's not quite true. I assume you know the thing you
left out: system scope threads compete against all the other
system scope threads in the system (from all applications, not
just within one application).


All this debate about the merits of process scope threads and fair
scheduling is great. But tell me, who was working on making this stuff
work well quickly and reliably (i.e. work well)? No one! I don't care
what AIX or Solaris or what else may or may not have done, who was making this work well for FreeBSD? Having a slow a thread subsystem is
a serious detriment, no matter how nice and flexible it looks on paper.

Process scope threads work well in libpthread. System scope
threads work well and fast in libthr. I think most people's
concept of "fast" as applied to process scope threads doesn't
quite mesh well with the fact that process scheduling is fair.

--
DE
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