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<p class=MsoNormal>I’ve recently discovered (and perhaps I should have
known this earlier) it’s possible to create a reasonably high performance
lock-free list/dictionary/stack/queue structure under C#.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Julian Bucknall has posted the sourcecode to a bunch of
these here: <a href="http://www.boyet.com/articles/lockfreestack.html">http://www.boyet.com/articles/lockfreestack.html</a>
<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>One of the big performance issues with OpenSim is our
overreliance on locking data structures, which can cause issues when those
locks don’t release in a timely manner. If we switched to lockless
structures – we could effectively eliminate those issues. (and probably
create new ones.)<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Does anyone have any opposition if we try to replace some of
the core structures with lock-free versions, and then removing the locks on
them? I’m thinking Scene.Entities, Scene.Presences would be two good targets
for the first lot, then maybe we can attack some deeper bits later.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Adam<o:p></o:p></p>
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