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<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>All<font color=navy><span style='color:navy'> </span></font><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I am experiencing some strange behaviour with RTEMS
message queues, although I suspect the problem may more to be with the main
configuration of the application.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I have a multi-threaded system, with a central
logging thread. Information is sent from each thread to the logging thread via
a single logging thread message queue. At the moment the logging thread simply
uses a printf to output the messages it receives. The behaviour we are seeing
though is that the logging thread is in a certain instances reading the
messages out of the queue in the wrong order and it also seems that some
messages are going missing all together. Monitoring the return of the
rtems_message_queue_send does not seem to reveal any issues with
RTEMS_SUCCESSFUL returned every time. An example of what I am seeing is as
follows:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Sen<font color=navy><span
style='color:navy'>t</span></font>: Message 1<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Sen<font color=navy><span
style='color:navy'>t</span></font>: Message 2<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Sen<font color=navy><span
style='color:navy'>t</span></font>: Message 3<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Sen<font color=navy><span
style='color:navy'>t</span></font>: Message 4<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Sen<font color=navy><span
style='color:navy'>t</span></font>: Message 5<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Sen<font color=navy><span
style='color:navy'>t</span></font>: Message 6<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Sen<font color=navy><span
style='color:navy'>t</span></font>: Message 7<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'> LOGGING
THREAD<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Read: Message 1<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Read: Message 2<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Read: Message 4<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Read: Message 3<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:36.0pt'><font size=2 face=Arial><span
lang=EN-GB style='font-size:10.0pt;font-family:Arial'>Read: Message 5<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Messages 3 and 4 are out of order and 6 and 7 never
seem to get through.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Does anyone have any ideas as to why this may be
happening? I am using RTEMS 4.8.1.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Kind regards<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>
Jamie<font color=navy><span style='color:navy'><o:p></o:p></span></font></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
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