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<div>Hello Max,</div>
<div>Though I have not analyzed the missing UL poll response, few of my observations from the pcap file attached is mentioned below</div>
<ol style="margin:0;padding-left:36pt;">
<li>There seems to be difference in FN UL versus DL being processed at any given time by the order of approx. 10 FNs, example given below</li></ol>
<ol type="a" style="margin:0;padding-left:72pt;">
<li>Packet 7174 , FN 1137361 in DL @ 15:33:22.511809393</li><li>Packet 7190, FN 1137361 in UL @ 15:33:22.559427972</li><li>From above example difference in time is 48milliseconds or approx.. 10FN duration</li></ol>
<ol start="2" style="margin:0;padding-left:36pt;">
<li>For processing DL timeslots 2 to 6 at any given DL FN time taken seems to be approx. 3milliseconds, example given below</li></ol>
<ol type="a" start="4" style="margin:0;padding-left:72pt;">
<li>Packet 7174 , FN 1137361 in DL @ 15:33:22.511809393 for TS 2</li><li>Packet 7178, FN 1137361 in DL @ 15:33:22.514310379 for TS 6</li></ol>
<div> </div>
<div>Please let me know if these are known behavior in your integration environment ? </div>
<div>These time variations may have an impact on the poll response behavior from MS as well.</div>
<div> </div>
<div>Regards</div>
<div>Saurabh</div>
<div> </div>
<div>-----Original Message-----<br>
From: Max [<a href="mailto:msuraev@sysmocom.de">mailto:msuraev@sysmocom.de</a>] <br>
Sent: Thursday, February 25, 2016 3:58 PM<br>
To: osmocom-net-gprs@lists.osmocom.org; Saurabh Sharan <Saurabh.Sharan@radisys.com><br>
Subject: PCU scheduling and PACCH timeout question</div>
<div> </div>
<div>Hello.</div>
<div> </div>
<div>I'm trying to debug issue with current OsmoPCU master when some basebands ignore polling requests.</div>
<div> </div>
<div>The debug output from RLCMAC layer and corresponding .pcap files are attached.</div>
<div>The issue appears somewhere after line 112 in debug.log The corresponding packet in pcu.pcapng is 6866</div>
<div> </div>
<div>After receiving PACKET_CONTROL_ACK from phone we're trying to schedule polling at FN 1137123 (see packet 6869 in pcap) and than at FN 1137127 (packet 6874) which subsequently fails.</div>
<div>This seems suspiciously close but I have not found in the spec yet if this is legitimate thing to do.</div>
<div> </div>
<div>There are several other occurrences like that in both log and pcap.</div>
<div> </div>
<div>Have you experienced something like this? Do you have an idea why only some basebands are affected while others work fine?</div>
<div> </div>
<div>--</div>
<div>Max Suraev <<a href="mailto:msuraev@sysmocom.de">msuraev@sysmocom.de</a>> <a href="http://www.sysmocom.de/">http://www.sysmocom.de/</a> =======================================================================</div>
<div>* sysmocom - systems for mobile communications GmbH</div>
<div>* Alt-Moabit 93</div>
<div>* 10559 Berlin, Germany</div>
<div>* Sitz / Registered office: Berlin, HRB 134158 B</div>
<div>* Geschaeftsfuehrer / Managing Directors: Holger Freyther, Harald Welte</div>
<div> </div>
<div> </div>
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