Summary of osmo-pcu failures/defects

This is merely a historical archive of years 2008-2021, before the migration to mailman3.

A maintained and still updated list archive can be found at https://lists.osmocom.org/hyperkitty/list/osmocom-net-gprs@lists.osmocom.org/.

Holger Hans Peter Freyther hfreyther at sysmocom.de
Sun Nov 24 18:05:35 UTC 2013


Hi,

I have added rate counters to the PCU and noticed that a lot of frames
in the DL are re-sent without there actually being any NACK or
transmission errors. I have also re-produced a "stall" by just using
ping with a big enough data size and a low enough interval (the PCU
appears to transmit the ICMP PING but the MS never gets to send a PONG
packet).

In both cases it could be a scheduling issue (e.g. we don't schedule
the UL Packet ACK/NACK). Is any of you aware of it? I had already
highlighted that the scheduling is not fair. I wonder if we are seeing
starvation (and will re-factor to be able to unit test this).

In terms of scheduling. For the SBA we are already having a reservation
that we try to honor in multiple places. Maybe it is time to extend it
and have more reservations?

holger

-- 
- Holger Freyther <hfreyther at sysmocom.de>       http://www.sysmocom.de/
=======================================================================
* sysmocom - systems for mobile communications GmbH
* Schivelbeiner Str. 5
* 10439 Berlin, Germany
* Sitz / Registered office: Berlin, HRB 134158 B
* Geschaeftsfuehrer / Managing Directors: Holger Freyther, Harald Welte





More information about the osmocom-net-gprs mailing list