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<p>Good day,</p>
<p>I am testing the dispatcher module, using Kamailio as stateless
proxy. I have a pool of UAC (scripts in SIPP) and a pool of UAS
(also scripts in SIPP) for the destinations. Kamailio version is
kamailio-5.3.3-4.1.x86_64.</p>
<p>Problem I have is, if UAS responds 180 and 200 OK to Invite
immediately, sometimes they are propagated out of order. 200 OK
before 180, like this :</p>
<p><img moz-do-not-send="false" src="cid:part1.DB2D0D68.919D3099@sixbell.com" alt="" width="597" height="209"><br>
<br>
</p>
<p>UAS is 172.30.4.195:5061. UAC is 172.30.4.195:5080. Kamailio is
192.168.253.4:5070</p>
<p>Difference between 180 and 200 is just about 50 microseconds. </p>
<p>My guess is that both messages are received by different
instances of Kamailio, and then because of context switches,
even though the 180 is received before, that process ends after
the processing of 200. However, I had the idea that in order to
avoid these problems the kamailio processes synchronized with
each other using a shared memory. I tried using stateful proxy
and I obtained the same result.</p>
<p>By the way, anyone has any idea about how Kamailio's share
memory is implemented? It clearly does not use the typical
system calls shmget(), shmat(), because they are not shown by
ipcs command.</p>
<p>Before posting here I googled, but I couldn't find anything
related to this. I can't believe I am the only one who ever had
this problem, so I guess I am doing something wrong...</p>
<p>Please, any help. I'm really stuck on this.</p>
<p>Thanks.</p>
<pre class="moz-signature" cols="72">--
Luis Rojas
Software Architect
Sixbell
Los Leones 1200
Providencia
Santiago, Chile
Phone: (+56-2) 22001288
<a class="moz-txt-link-freetext" href="mailto:luis.rojas@sixbell.com">mailto:luis.rojas@sixbell.com</a>
<a class="moz-txt-link-freetext" href="http://www.sixbell.com">http://www.sixbell.com</a>
</pre>
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<pre class="moz-signature" cols="72">--
Luis Rojas
Software Architect
Sixbell
Los Leones 1200
Providencia
Santiago, Chile
Phone: (+56-2) 22001288
<a class="moz-txt-link-freetext" href="mailto:luis.rojas@sixbell.com">mailto:luis.rojas@sixbell.com</a>
<a class="moz-txt-link-freetext" href="http://www.sixbell.com">http://www.sixbell.com</a>
</pre>
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