For balancing load across congested cells and across congested TCH/*
kinds, instead of comparing the number of lchans above the configured
congestion threshold, compare the percent of lchans of overload.
In short, using a percentage prevents cells with less min-free-slots to
fill up 100% while neighbor cells still may have several free lchans
available.
An obvious example of why this is desirable is illustrated by
test_balance_congestion_by_percentage.ho_vty:
Cell A has min-free-slots 2, and has all slots occupied.
Cell B has min-free-slots 4, and has 2 slots remaining free.
If we count congested lchans as in current master: cell A has a
congestion count of 2: two more lchans in use than "allowed". If we move
one lchan over to cell B, it ends up with a congestion count of 3, which
is worse than 2. So when counting lchans, we decide that cell A should
remain full.
Instead, when comparing percentage of remaining lchans, we would see
that cell A is loaded 100% above congestion (2 of 2 remaining lchans in
use), but when moving one lchan to cell B, that would only be 75% loaded
above its treshold (3 of 4 remaining lchans in use). So a percentage
comparison would cause a handover to cell B.
Related: SYS#5259
Change-Id: I55234c6c99eb02ceee52be0d7388bea14304930f
This new CTRL interface allows users of this BSC (such as attached PCU)
to gather neighbor information.
This interface is needed for PCU to translate ARFCN+BSIC keys provided
by MS in the Um side into CGI + RAC keys used to identify target cells
in RIM procedures against SGSNs on the Gb interface.
This patch extends the already existing neighbor information storage in
the VTY by allowing storage of CGI + RAC (RAC couldn't be stored
beforehand).
Related: SYS#4909
Depends: libosmocore.git Change-Id If48f412c32e8e5a3e604a78d12b74787a4786374
Change-Id: Ib07c9d23026332a207d4b7a0f7b4e76c0094e379
Considering feedback by a customer, we prefer congestion balancing by
using percentage of overload instead of number of lchans of overload.
This test is intended to illustrate the change in behavior.
Change-Id: I314915718f66aec50e8dcf94569b0a52ca34b96f
When evenly distributing congestion across cells, count the number of
occupied lchans surpassing congestion, and not the overall number of
free lchans -- which disregards congestion thresholds.
Fix the bugs shown by
test_congestion_no_oscillation.ho_vty
test_balance_congestion_tchf_tchh.ho_vty
This implements a simple calculation for congestion load by counting
lchans in use above congestion. An improvement of this calculation
using percent follows in I55234c6c99eb02ceee52be0d7388bea14304930f.
Related: SYS#5259
Change-Id: Icb373dc6bfc9819446db5e96f71921781fe2026d
With 'set-ts-use', it is convenient to build a scenario of lchan usage,
but still inconvenient to send measurement reports to all lchans.
I need this for testing congestion-check, because each lchan needs to
have at least one measurement report, or congestion check is skipped.
Example:
set-ts-use trx 0 0 states * TCH/F TCH/F - - TCH/HH TCH/HH TCH/H-
meas-rep lchan * * * * rxlev 10 rxqual 0 ta 0
This patch adds the '*' for the lchan arguments, usually being bts idx,
trx idx, timeslot idx and subslot idx.
Use lchan wildcards at the appropriate places to shorten some tests.
Change-Id: I441f92348508d45e1069a3dfa1ff3842dbba97d6
Store the number of free lchans and the min-free-slots settings in
ho_candidate, instead of figuring those out in various places, to make
it easier to read.
Prepare for upcoming patch which also requires these values to fix a
bug.
Change-Id: Ie6ca5af5e8d0ebb8deaaaa637e2728008ecba517
So far it is often confusing which cell a specific member refers to.
Clarify lchan, bts, ... to current.lchan, target.bts, ...
Also move the rxlev_{current,target} to {current,target}.rxlev.
Eliminate numerous local variables to make it easier to read which side
is being used (e.g. "c->target.bts" instead of just "bts").
No functional change.
Change-Id: I06898eb745a5be548df0b76fa760ce790cfab3ed
Also add test_congestion_no_oscillation2.ho_vty which is an almost
identical scenario that does not show the bug -- because it has two more
TCH/H available in BTS 1, showing the strange behavior of the algorithm.
Related: SYS#5259
Change-Id: Idf88b4cf3d2f92f5560d73dae9e59af39d0494c0
Echo each handover_test command on the test output, to help with
understanding the exact point of a test failure.
Even nicer would be a general echo of all VTY commands, but the VTY
currently does not support that feature. Refraining from a libosmocore
patch just for these test scripts...
Change-Id: Ifc307a7d0b7e3caa355f8cee88778762b529ad71
Similar to chan act handling, clarify and safeguard HO Request handling.
Ensure that each HO Request is handled by the test script.
Place unhandled HO Requests in new_ho_req pointer, moving to last_ho_req
upon handling it. Instead of the got_ho_req flag and additional
ho_req_lchan pointer, just keep a last_ho_req pointer.
Drop a bunch of utterly useless RSL message parsing code.
Fix unhandled HO Request in test_max_handovers.ho_vty.
Change-Id: I0a664f24d7dd3d7b254b29675fdc49cd70a1a480
Do not clear pending chan act requests when sending a measurement report
or starting congestion check. This potentially left channel activations
unnoticed and dangling, e.g. for repeated meas-rep.
A typical test should indeed handle pending channel activation requests
before potentially triggering more, safeguard against this by asserting
that only one channel activation is pending.
Place unhandled channel activations in new_chan_req pointer, moving to
last_chan_req upon handling it. Instead of the got_chan_req flag and
additional chan_req_lchan pointer, just keep a last_chan_req pointer.
Change-Id: If06587058798d96afca86358030dc0c1c3c6df39
Fix flaws in picking a candidate for congestion resolution, shown in
recently added tests.
- For TCH/H->TCH/F upgrading, do not favor moving to a weaker neighbor
cell.
- When comparing dynamic timeslots on the same cell, favor a dynamic
timeslot that frees an entire dyn TS even though the target rxlev
differs.
Do not separate the passes for inter-cell and intra-cell candidates:
before, the inter-cell pass would already pick a candidate and start
handover, even though the subsequent intra-cell pass would have revealed
a better candidate. Join the intra-cell considerations into
pick_better_lchan_to_move().
The intra-cell pass was separate, because it would find the *weakest*
current rxlev, to give a TCH/H to TCH/F upgrade to the currently weakest
lchan.
Instead of the separate pass for weakest rxlev, in addition to the
target cell's rxlev, also consider the rxlev *change* in
pick_better_lchan_to_move(): For candidates that do not change the rxlev
(usually those that stay in the same cell) and that upgrade to TCH/F,
favor a candidate with weaker current rxlev.
Completely revisit the conditions in pick_better_lchan_to_move() to
yield the desired prioritization of candidate preferences.
In three handover tests, remove the "FAIL" comments and adjust to now
expect the actually desired behavior.
Related: SYS#5032
Change-Id: I2704899c85c35dfd4eba43468452483f40016ca2
Instead of passing the TCH/H -> TCH/F bias (AFS bias) in local
variables, rather store it in the ho_candidate struct next to the other
rxlev related values.
Add the AFS bias to the compared rxlev in pick_better_lchan_to_move().
Modify pick_better_lchan_to_move() to simpler semantics of returning
either a or b.
No functional change.
Change-Id: I73860abdf2a77270ca4851ad58c09767d1bb08f1
Store the rxlev of the current lchan and the target BTS in the
ho_candidate, to clarify the code.
No functional change, cosmetically prepare for
I2704899c85c35dfd4eba43468452483f40016ca2.
Change-Id: Ie6c165e17bb3c99eebc967a6bb02529db8bdfc98
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
The aim is to pin the current basic behavior of handover decision 2,
before modifying the algorithm conditions to fix some bugs in upcoming
patches -- so far no test ensures this particular detail.
Change-Id: I68cdda21ef59c464f0af3c2eee356623e58ea1cd
Some tests want to repeat the same measurement report, typically 10
times to fill the averaging window. Instead of 10 lines saying
'meas-rep ...', allow 'meas-rep repeat 10 ...'.
Change-Id: Ib2fa81a449fb73ec7c458b0e6877d6561c79a846
In handover_decision_2.c, instead of repeating a similar loop four
times, put that loop in a function and parameterize it.
Prepare for a fix of two problems in handover decision 2, see
I2704899c85c35dfd4eba43468452483f40016ca2.
Change-Id: I7c32d08e490a88a7f044b0a71dc4b07d748dd572
An upcoming test that uses set-ts-use to release used lchans uncovered
an incomplete release, keeping the lchans occupied due to a missing
release ack. Always ack the release.
Change-Id: Ia22906bfbfcc48b7bd08473a2b17f6b0554687d3
We decided not to keep the handover_test script expected outputs
(osmo-bsc's logging output) in the source tree. Hence do not fail the
handover_tests when the output differs, just show a diff (if at all).
Change-Id: I3e9e123b41be71d1fcd9576b0bd38d2fd32353b4
We decided not to keep the handover_test script expected outputs
(osmo-bsc's logging output) in the source tree. For manual comparison,
they are still produced by 'handover_tests.sh -u', ignore them.
Change-Id: I5dda03f21b568e07cf26501ba2e0683108d408b6
Adding SMSCB messages to a BTS so far only worked if there were
existing messages with a lower scheduling period than the new message.
Before this patch, it fails for new messages if they are of equal or
lower scheduling period than the existing messages.
Change-Id: I69a05b22200b3a1ee406b0673553e135603d723b
None of those commands apply immediately, they only affect newly
established logical channels. The reason is that the related
IEs are only getting sent on channel activation / assignment.
Change-Id: I06c7851115fb31d1eb92c400d9724f4f051bd171
Related: SYS#5114
Both commands are basically doing the same thing, so we can merge
them into a single command by adding a parameter to the command
string. The VTY syntax remains the same:
do-something foo
do-something bar
becomes:
do-something (foo|bar)
This change reduces code duplication.
Change-Id: Ibe98718d8f4933926eed0e622109c9c82537f526
Related: SYS#5114
Presence of these lines in the config file does not necessarily mean
that the BTS will not perform measurement pre-processing. It actually
means that the BSC would not include the optional IEs related to the
measurement pre-processing, so the BTS may still apply its default
averaging algorythm with default parameters.
In order to avoid potential confusion, let's avoid printing them.
Change-Id: I585b5bf4fde93d66e47666e0fa9903f21a268b51
Related: SYS#4918
This fixes the following heap overflow in the SMSCB scheduler:
==109051==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x60d00003a9a0 at pc 0x55d77e4bedf1 bp 0x7fff8cdc4240 sp 0x7fff8cdc4238
READ of size 8 at 0x60d00003a9a0 thread T0
#0 0x55d77e4bedf0 in bts_smscb_sched_add_before /space/home/laforge/projects/git/osmo-bsc/src/osmo-bsc/cbch_scheduler.c:64
Change-Id: If529aa905336a1b9e7a36e931c165df0ba9899ad
The existing code uses short-lived FSMs which are allocated straight
before START, and which are free'd after DONE state is reached.
While that works, it makes state introspection a bit hard, as one
cannot show the FSM states, etc.
Let's change to a different model where the per-OM2k-MO FSMs are
always around (in state INIT after object creation). While at it,
also introduce a RESET event that can reset each FSM instance back
to INIT state, i.e. in case of OML link failure.
Change-Id: Ia37cffff5c451e1d79a52ccae41ab5718b4661d4
There is only one parameter in command:
repeat dl-facch (command|all)
so indeed argv[0] must be used instead of argv[1].
Change-Id: I01efff109a33791e13b0149fc47c792d3266da71
Related: SYS#5114
Vadim Yanitskiy
Neels Hofmeyr
Pau Espin
Harald Welte