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<p class=MsoNormal><span style='font-size:11.0pt;color:#1F497D'>Yes you need
something. <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;color:#1F497D'>You can use
InterlockedIncrement and InterlockedDecrement instead of Inc/Dec.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;color:#1F497D'>Myles.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:
"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;
font-family:"Tahoma","sans-serif"'> delphi-bounces@delphi.org.nz
[mailto:delphi-bounces@delphi.org.nz] <b>On Behalf Of </b>Ross Levis<br>
<b>Sent:</b> Tuesday, 17 July 2007 04:02<br>
<b>To:</b> 'NZ Borland Developers Group - Delphi List'<br>
<b>Subject:</b> [DUG] Threads again<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I’m trying to avoid using a critical section due to
time overhead. In one thread I have a global integer incrementing roughly
every 20 milliseconds using Inc(x,y). In another thread I have the same
integer decreasing using Dec(x,y) at about the same speed.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Is it critical to have these in a critical section?
I’ve been testing it here for a few days continuously and it appears to
work fine without one.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Even with a dual processor and each thread running on a
separate processor, is it possible for one memory location to be written
precisely at the same time? It doesn’t matter which occurs first or
in which order.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Cheers,<o:p></o:p></p>
<p class=MsoNormal>Ross.<o:p></o:p></p>
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