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<P><FONT size=2>Hello RTEMS users,<BR>I am experiencing a problem with the
interaction of tasks and queues and wanted to know if I was doing anything
wrong.<BR><BR>Here is the scenario:<BR>=====================<BR></FONT></P><FONT
size=2><FONT face=Arial>
<P><IMG align=baseline alt="" border=0 hspace=0
src="cid:515201210@27102000-1e82"></P></FONT>
<P> </P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial
size=2>Problem:</FONT></SPAN></P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial size=2>The
problem is that the Task B seems to suspend and not wake although there is a
message pending in Queue B.</FONT></SPAN></P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial size=2>If a
second message is sent later then the Task B resumes and processes both
messages.</FONT></SPAN></P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial
size=2></FONT></SPAN><SPAN class=515201210-27102000><FONT color=#000000
face=Arial size=2></FONT></SPAN> </P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial size=2>My
question is : </FONT></SPAN></P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial size=2>Am I
causing problems by assigning a higher priority to sporadic Tasks A & B than
the periodic Rate Monotonic task? </FONT></SPAN></P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial size=2>Is it
possible that because there is a RM task present that the sporadic task B does
not get resumed until a 2nd message enters the queue? </FONT></SPAN></P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial size=2>Can the
"readying" of a RM task have priority over the sporadic task B if the
task B's priority is greater than that of the RM task?</FONT></SPAN></P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial size=2>I have
read in the users manual for RTEMS that critical RM tasks should have higher
priority than the non-critical tasks. When "relaxing the rules a bit"
the sporadic tasks are okay as long as these sporadic tasks don't take much time
and can be treated the same as ISRs for calculating the processor
utilisation.</FONT></SPAN></P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial size=2>Any
comments would be helpful</FONT></SPAN></P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial
size=2>regards</FONT></SPAN></P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial
size=2></FONT></SPAN><SPAN class=515201210-27102000><FONT color=#000000
face=Arial size=2>John Bebbington.</FONT></SPAN></P>
<P><SPAN class=515201210-27102000><FONT color=#000000 face=Arial
size=2></FONT></SPAN> </P>
<P><BR>
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