Change in osmo-bsc[master]: handover_test: show ineffective intra-cell choice

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/gerrit-log@lists.osmocom.org/.

neels gerrit-no-reply at lists.osmocom.org
Tue Jan 5 22:28:46 UTC 2021


neels has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmo-bsc/+/21975 )


Change subject: handover_test: show ineffective intra-cell choice
......................................................................

handover_test: show ineffective intra-cell choice

In handover decision 2, choosing an lchan to move so far takes into
account only the absolute current rxlev, and it fails to look at the
*difference* in rxlev between source and target cell.

My recent feature to favor freeing half-used TCH/H does in fact not work
well. The main reason why the test for that feature passes is that all
lchans in the test get identical measurements -- which is unrealistic.

A test with differing ratings uncovers the flaw in comparing intra-cell
candidates.

Related: SYS#5032
Change-Id: Iabce1ab44b496833c19d999fc3f2903d835c357f
---
M tests/handover/test_dyn_ts_favor_moving_half_used_tch_h.ho_vty
1 file changed, 36 insertions(+), 5 deletions(-)



  git pull ssh://gerrit.osmocom.org:29418/osmo-bsc refs/changes/75/21975/1

diff --git a/tests/handover/test_dyn_ts_favor_moving_half_used_tch_h.ho_vty b/tests/handover/test_dyn_ts_favor_moving_half_used_tch_h.ho_vty
index b90236d..9d88c86 100644
--- a/tests/handover/test_dyn_ts_favor_moving_half_used_tch_h.ho_vty
+++ b/tests/handover/test_dyn_ts_favor_moving_half_used_tch_h.ho_vty
@@ -1,15 +1,46 @@
-# Congestion check: favor moving a TCH/H that frees a half-used dyn TS completely
+# Congestion check: favor moving a TCH/H that frees a half-used dyn TS completely.
+# The algorithm should notice that this is about moving an lchan within the same cell, so all candidates will remain
+# with unchanged rxlev after a re-assignment; hence the current rxlev for each candidate should not make a difference.
 
 create-bts trx-count 1 timeslots c+s4 dyn   dyn    dyn    dyn    dyn  - -
+network
+ handover2 min-free-slots tch/h 6
+
+# Test with identical rxlev across lchans (trivial and unrealistic)
 set-ts-use    trx 0 0     states *    pdch  TCH/HH TCH/H- TCH/HH pdch - -
 meas-rep lchan 0 0 2 1 rxlev 30 rxqual 0 ta 0
 meas-rep lchan 0 0 3 0 rxlev 30 rxqual 0 ta 0
 meas-rep lchan 0 0 4 0 rxlev 30 rxqual 0 ta 0
 meas-rep lchan 0 0 4 1 rxlev 30 rxqual 0 ta 0
-# pick one to move:
-network
- bts 0
-  handover2 min-free-slots tch/h 6
 congestion-check
 expect-ho from lchan 0 0 3 0 to lchan 0 0 1 0
 expect-ts-use trx 0 0     states *    TCH/F TCH/HH pdch TCH/HH pdch - -
+
+# clear measurements for the next run
+set-ts-use    trx 0 0     states *    pdch pdch pdch pdch pdch - -
+
+# Check that a weaker rxlev coming up earlier in the congestion checking loop does not override the favored half-used
+# TCH/H
+set-ts-use    trx 0 0     states *    pdch  TCH/HH TCH/H- TCH/HH pdch - -
+meas-rep lchan 0 0 2 1 rxlev 30 rxqual 0 ta 0
+meas-rep lchan 0 0 3 0 rxlev 31 rxqual 0 ta 0
+meas-rep lchan 0 0 4 0 rxlev 32 rxqual 0 ta 0
+meas-rep lchan 0 0 4 1 rxlev 33 rxqual 0 ta 0
+congestion-check
+expect-ho from lchan 0 0 3 0 to lchan 0 0 1 0
+expect-ts-use trx 0 0     states *    TCH/F TCH/HH pdch TCH/HH pdch - -
+
+# clear measurements for the next run
+set-ts-use    trx 0 0     states *    pdch pdch pdch pdch pdch - -
+
+# Check that a weaker rxlev coming up later in the congestion checking loop does not override the favored half-used
+# TCH/H
+set-ts-use    trx 0 0     states *    pdch  TCH/HH TCH/H- TCH/HH pdch - -
+meas-rep lchan 0 0 2 1 rxlev 34 rxqual 0 ta 0
+meas-rep lchan 0 0 3 0 rxlev 33 rxqual 0 ta 0
+meas-rep lchan 0 0 4 0 rxlev 32 rxqual 0 ta 0
+meas-rep lchan 0 0 4 1 rxlev 31 rxqual 0 ta 0
+congestion-check
+# FAIL: should still pick lchan 0 0 3 0!
+expect-ho from lchan 0 0 4 1 to lchan 0 0 1 0
+expect-ts-use trx 0 0     states *    TCH/F TCH/HH TCH/H- TCH/H- pdch - -

-- 
To view, visit https://gerrit.osmocom.org/c/osmo-bsc/+/21975
To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings

Gerrit-Project: osmo-bsc
Gerrit-Branch: master
Gerrit-Change-Id: Iabce1ab44b496833c19d999fc3f2903d835c357f
Gerrit-Change-Number: 21975
Gerrit-PatchSet: 1
Gerrit-Owner: neels <nhofmeyr at sysmocom.de>
Gerrit-MessageType: newchange
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osmocom.org/pipermail/gerrit-log/attachments/20210105/19b8ad8e/attachment.htm>


More information about the gerrit-log mailing list