Bug #1759
open
Wrong calculation of DL window size for DL assignment
Added by arvind.sirsikar almost 8 years ago.
Updated over 4 years ago.
Description
Hi,
When we create DOWNLINK TBF without existing UPLINK TBF i.e DL assignment on PCH case, The calculation of window size is found to be incorrect.
Description:
4 time slots is configured for DL and osmo-pcu.cfg is configured as window-size 64 104.
When we try to do IPERF in DL direction, PCU allocates window-size as 160 but configures 4 time slots
as seen by PCU VTY. Below is the result of VTY output.
DL TBFs
TBF: TFI=0 TLLI=0xf73d2ece (valid) DIR=DL IMSI=901555000001280
created=1095 state=0000000a 1st_TS=4 1st_cTS=6 ctrl_TS=6 MS_CLASS=0/1
TS_alloc=4 5 6! 7 CS=MCS-9 WS=160 V(A)=12 V(S)=12 nBSN=138
But we see proper calculation of window-size when DL assignement is done on PACCH. as seen by VTY interface below
DL TBFs
TBF: TFI=0 TLLI=0xf73d2ece (valid) DIR=DL IMSI=901555000001280
created=1095 state=0000000a 1st_TS=4 1st_cTS=6 ctrl_TS=6 MS_CLASS=0/1
TS_alloc=4 5 6! 7 CS=MCS-9 WS=480 V(A)=138 V(S)=139 nBSN=138
Thanks,
Aravind Sirsikar
- Assignee changed from arvind.sirsikar to 4368
- Assignee changed from 4368 to msuraev
- Priority changed from High to Normal
- Priority changed from Normal to High
I don't see explicit tests for it - only as part of larger TBF tests. So the first step would to add such a test.
- Project changed from Cellular Network Infrastructure to OsmoPCU
- Related to Feature #1533: Separate the window handling from the TBF more clearly added
- Status changed from New to In Progress
- % Done changed from 0 to 20
Related gerrit 5355, 5336-5341 are under review. Remaining parts: clearly differenciate between CCCH and PACCH assignment, figure out whyit makes a difference to window size calculations and test with different window sizes settings and available channels.
- Status changed from In Progress to Stalled
- Status changed from Stalled to In Progress
- % Done changed from 20 to 30
Patches were merged. Additional gerrit 5786 was sent for review.
5786 is merged, needs additional testing.
The window size parameter in vty defined as follows:
window-size <0-1024> [<0-256>]
Window size configuration (b + N_PDCH * f)
Base value (b)
Factor for number of PDCH (f)
So the configuration window-size 64 104 means that WS(1TS) = 64 + 1 * 104 = 168 and WS(4TS) = 64 + 4 * 104 = 480. By default f = 0.
- Related to Bug #1524: PACCH on the wrong timeslot added
In addition to difference between PACCH and CCCH, the TBF can be assigned via CCCH but configrmed via PACCH (see rcv_control_ack() function). This and the related #1524 makes it harder to reproduce this reliably.
Related gerrit 6239 is under review.
Hi Max,
On Mon, Feb 05, 2018 at 03:45:50PM +0000, msuraev [REDMINE] wrote:
In addition to difference between PACCH and CCCH, the TBF can be assigned via CCCH but configrmed via PACCH (see rcv_control_ack() function). This and the related #1524 makes it harder to reproduce this reliably.
would it be possible to disable certain variants as a temporary hack?
- Status changed from In Progress to Stalled
Needs a way to reproduce this reliably.
- Assignee changed from msuraev to 4368
- Assignee changed from 4368 to msuraev
- Assignee changed from msuraev to lynxis
- Assignee deleted (
lynxis)
This needs a TTCN3 test in PCU_Tests_RAW.
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