Re: [simspark-devel] Fwd: about multi-thread implementation

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<p><span>Hi Yuan,</span></p>
<p style="margin-bottom: 0cm; margin-top: 0pt;"><span></span></p>
<span><br>
<style type="text/css">blockquote {color: navy !important; background-color: RGB(245,245,245) !important; padding: 0 15 10 15 !important; margin: 15 0 0 0; border-left: #1010ff 2px solid;}  blockquote blockquote {color: maroon !important; background-color: RGB(235,235,235) !important; border-left-color:maroon !important}  blockquote blockquote blockquote {color: green !important; background-color: RGB(225,225,225) !important; border-left-color:teal !important}  blockquote blockquote blockquote blockquote {color: purple !important; background-color: RGB(215,215,215) !important; border-left-color: purple !important}  blockquote blockquote blockquote blockquote blockquote {color: teal !important; background-color: RGB(205,205,205) !important; border-left-color: green !important}</style><i><b>Hedayat
Vatankhah <a class="moz-txt-link-rfc2396E"   href="mailto:hed...@ai...">&lt;hed...@ai...&gt;</a></b></i>
wrote on 03/09/2008
10:45:48 PM:</span><br>
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  <span><br>
  <style type="text/css">blockquote {color: navy !important; background-color: RGB(245,245,245) !important; padding: 0 15 10 15 !important; margin: 15 0 0 0; border-left: #1010ff 2px solid;}  blockquote blockquote {color: maroon !important; background-color: RGB(235,235,235) !important; border-left-color:maroon !important}  blockquote blockquote blockquote {color: green !important; background-color: RGB(225,225,225) !important; border-left-color:teal !important}  blockquote blockquote blockquote blockquote {color: purple !important; background-color: RGB(215,215,215) !important; border-left-color: purple !important}  blockquote blockquote blockquote blockquote blockquote {color: teal !important; background-color: RGB(205,205,205) !important; border-left-color: green !important}</style><i><b>"Yuan
Xu" <a moz-do-not-send="true" class="moz-txt-link-rfc2396E"   href="mailto:xuy...@gm...">&lt;xuy...@gm...&gt;</a></b></i>
wrote on 03/09/2008 12:19:22 PM:</span><br>
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    <pre wrap="">[...]
 I attached the testing server to this mail, could you test it in your system?
  </pre>
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OK, I'll test it ASAP. Interesting!<br>
</blockquote>
Unfortunately, it doesn't work on my system :(<br>
<br>
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    <pre wrap=""> There is another issue should be in mind is that
 the multi-threads increase the sense act latency,
 it makes agent behavior unlike in the singled-thread.
 I think this will make teams in trouble while changing from
 singled-thread to multi-threads.
 What do you think about it?  </pre>
  </blockquote>
Sorry, would you please explain more about the reason of this increased
latency? In both single threaded and multi-threaded modes StartCycle()
is called immediately after EndCycle(). What increases the latency?<br>
</blockquote>
OK! I read the code and understood what you said. Yes, the variable
latency is not desirable specially that it is not predictable :(<br>
<br>
<blockquote   style="border-left: 2px solid rgb(16, 16, 255); color: navy; background-color: rgb(245, 245, 245); padding-left: 15px;"   cite="mid:47D...@ai..." type="cite">And another question:
it seems that it is enough to call
SceneServer::Pre/PostPhysicsUpdate() functions once in a cycle. So, we
can apply the same change in Step() for single threaded mode (to call
PhysicsUpdate() function inside it's while loop instead of Update()
function and calling Pre/PostPhysicsUpdate() functions (and
GameControlServer::Update()) outside the while loop); right? It should
benefit performance a little.<br>
</blockquote>
Another thing: PrePhysicsUpdate received a deltaTime parameter. But
currently, it is called once per cycle in RunMultiThreaded. We should
either remove the parameter (I'm not sure but it might be unused!) or
put it inside the PhysicsUpdate while loop. Which one is better?<br>
<br>
Thanks,<br>
Hedayat<br>
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Thanks a lot,<br>
Hedayat<br>
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