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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Hi again!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-CA
style='font-size:10.0pt;font-family:Arial;color:navy'>Further testing shows
that the problem appears between version 3.6-1 (polling of XQ is functionnal)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-CA
style='font-size:10.0pt;font-family:Arial;color:navy'>And version 3.7-0
(polling specification of XQ is not taken into account, and is fixed at 100
polls per second.)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-CA
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-CA
style='font-size:10.0pt;font-family:Arial;color:navy'>Thanks,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-CA
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-CA
style='font-size:10.0pt;font-family:Arial;color:navy'>Francois<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span lang=EN-CA
style='font-size:10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span lang=FR style='font-size:
10.0pt;font-family:Tahoma;font-weight:bold'>De :</span></font></b><font
size=2 face=Tahoma><span lang=FR style='font-size:10.0pt;font-family:Tahoma'>
Boucher, François <br>
<b><span style='font-weight:bold'>Envoyé :</span></b> 9 janvier 2008 13:57<br>
<b><span style='font-weight:bold'>À :</span></b> 'simh@trailing-edge.com'<br>
<b><span style='font-weight:bold'>Objet :</span></b> 10ms delay on
ethernet communications</span></font><span lang=FR><o:p></o:p></span></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA style='font-size:
10.0pt;font-family:Arial'>Hi to all!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA 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-CA style='font-size:
10.0pt;font-family:Arial'>I am looking for help about the Ethernet driving of
the vax simulator. I see that there is some sort of a fixed delay of
about<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA style='font-size:
10.0pt;font-family:Arial'>10ms between the time a packet is received from the
network and the time it is treated in the simulator.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA 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-CA style='font-size:
10.0pt;font-family:Arial'>My host machine has an intel quad core 2.4GHz, 1033
MHz of FSB, 4MB cache per core, desktop, running Knoppix linux, version 5.1.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA style='font-size:
10.0pt;font-family:Arial'>It has Ethernet cards plugged into a Cisco 2924
switch, with all port speed fixed at 100Mbps.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA 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-CA style='font-size:
10.0pt;font-family:Arial'>I saw in the documentation that there is a parameter
for the polling frequency of the reception of packets, related to the XQ
devices of the simulator. By default, the parameter is 100 polls per
second, which is consistent with the 10ms delay observed.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA style='font-size:
10.0pt;font-family:Arial'>I did change the value of the polling parameter to
1000polls per second, but the delay stayed there on the simulator,
version 3.7-3<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA style='font-size:
10.0pt;font-family:Arial'>(The command I did was SET XQ POLL=1000)<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA 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-CA style='font-size:
10.0pt;font-family:Arial'>So, I tried to use a previous version of simh, in
this case, version 3.4, and when I adjusted the polling rate, I got a
diminution of the latency time for the reception of packets. This means
that between simh 3.4 and simh 3.7-3 there is maybe some broken code about the
control of the XQ polling rate. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA 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-CA style='font-size:
10.0pt;font-family:Arial'>Perhaps there is something else I could do to adjust
the polling rate on simh 3.7 but I don’t know what. Any suggestions
would be welcomed!<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA 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-CA style='font-size:
10.0pt;font-family:Arial'>Thanks,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-CA style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><st1:PersonName ProductID="Francois Boucher" w:st="on"><font
size=2 face=Arial><span lang=EN-CA style='font-size:10.0pt;font-family:Arial'>Francois
Boucher</span></font></st1:PersonName><font size=2 face=Arial><span
lang=EN-CA 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-CA 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-CA style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
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