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Oh -- it is so you can wait for more than 4 billion milliseconds, I guess.<BR>
The chunk size of the loop is roughly the maximum time WaitForSingleObject is allowed.<BR>
Ok.<BR>
<BR>
- Jay<BR> <BR>
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From: jay.krell@cornell.edu<BR>To: m3devel@elegosoft.com<BR>Date: Fri, 11 Dec 2009 14:05:56 +0000<BR>Subject: [M3devel] win32 AlertPause polls instead of one big wait?<BR><BR>
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Anyone know why Win32 AlertPause uses a polling loop instead of just one wait?<BR> <BR> <BR>I'm not sure this is going to work out, but:<BR> I'm "rewriting" stuff to use a separate event for alerting.<BR> alertable goes away<BR> There will be two events: <BR> waitEvent, for condition variables<BR> alertEvent, for alerting <BR> <BR> <BR>roughly speaking:<BR> <BR> <BR>AlertPause: WaitForSingleObject(alertEvent)<BR>AlertWait:<BR> alerted := WaitForMultipleObjects({alertEvent, waitEvent}) == WAIT_OBJECT_0)<BR>Alert(t): SetEvent(t.alertEvent);<BR>TestAlert: alerted := WaitForSingleObject(alertEvent, 0);<BR> <BR> <BR>It seems simple enough.<BR>That shows all the ingredients.<BR>That'll eliminate a lot of the global locking.<BR>And then one "last" iteration to use the Java code for condition variables and the global lock will be gone.<BR>You can't just use the Java code because it doesn't include alertability.<BR>You can't, I believe, draw a parallel to the pthreads code, because the Java code doesn't maintain a wait list with a mutex.<BR>The waiter/tickets/counter stuff is pretty clever -- I don't understand it yet..<BR> <BR> <BR> - Jay<BR> </body>
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