paging: Replace reqs waiting for retransmission with new incoming inital req if queue is full

If queue size (in transmit delay of requests) is too long (above
threshold) when a new initial incoming request arrives, instead of
directly discarding it, see if we can drop a pending retransmission and
insert the new one instead, in order to avoid losing initial requests.

This is done under the assumption that it is more important to transmit
intial requests than to retransmit already transmitted ones. The
rationale is that there's lower chances that an MS which didn't answer
lately will answer now (aka being reachable at the cell), so it's better
to allocate resources for new requests (new MS) which may be available
in the cell.

Change-Id: Idfd93254ae456b1ee08416e05479488299dd063d
Related: OS#5552

1 files changed, 2 insertions, 2 deletions

diff --git a/tests/timer.vty b/tests/timer.vty
index 731d134b2..9573a0922 100644
--- a/tests/timer.vty
+++ b/tests/timer.vty
@@ -35,7 +35,7 @@ net: X17 = 0 ms	Rounding threshold for all_allocated:* rate counters: round up t
 net: X18 = 60000 ms	Forget-sum period for all_allocated:* rate counters: after this amount of idle time, forget internally cumulated time remainders. Zero to always keep remainders. See also X16, X17. (default: 60000 ms)
 net: X25 = 5 s	Timeout for initial user data after an MSC initiated an SCCP connection to the BSS (default: 5 s)
 net: X3111 = 4 s	Wait time after lchan was released in error (should be T3111 + 2s) (default: 4 s)
-net: X3113 = 60 s	Maximum Paging Request Transmit Delay Threshold: If the estimated transmit delay of the messages of the paging queue surpasses this threshold, new incoming paging requests are discarded, hence limiting the size of the queue and maximum delay of its scheduled requests. X3113 also serves as the upper boundary for dynamic T3113 when estimating the expected maximum delay to get a response (default: 60 s)
+net: X3113 = 60 s	Maximum Paging Request Transmit Delay Threshold: If the estimated transmit delay of the messages in the paging queue surpasses this threshold, then new incoming paging requests will if possible replace a request in retransmission state from the queue or otherwise be discarded, hence limiting the size of the queue and maximum delay of its scheduled requests. X3113 also serves as the upper boundary for dynamic T3113 when estimating the expected maximum delay to get a response (default: 60 s)
 net: X3210 = 20 s	After L3 Complete, wait for MSC to confirm (default: 20 s)
 mgw: X2427 = 5 s	timeout for MGCP response from MGW (default: 5 s)
 
@@ -90,7 +90,7 @@ net: X17 = 0 ms	Rounding threshold for all_allocated:* rate counters: round up t
 net: X18 = 60000 ms	Forget-sum period for all_allocated:* rate counters: after this amount of idle time, forget internally cumulated time remainders. Zero to always keep remainders. See also X16, X17. (default: 60000 ms)
 net: X25 = 5 s	Timeout for initial user data after an MSC initiated an SCCP connection to the BSS (default: 5 s)
 net: X3111 = 4 s	Wait time after lchan was released in error (should be T3111 + 2s) (default: 4 s)
-net: X3113 = 60 s	Maximum Paging Request Transmit Delay Threshold: If the estimated transmit delay of the messages of the paging queue surpasses this threshold, new incoming paging requests are discarded, hence limiting the size of the queue and maximum delay of its scheduled requests. X3113 also serves as the upper boundary for dynamic T3113 when estimating the expected maximum delay to get a response (default: 60 s)
+net: X3113 = 60 s	Maximum Paging Request Transmit Delay Threshold: If the estimated transmit delay of the messages in the paging queue surpasses this threshold, then new incoming paging requests will if possible replace a request in retransmission state from the queue or otherwise be discarded, hence limiting the size of the queue and maximum delay of its scheduled requests. X3113 also serves as the upper boundary for dynamic T3113 when estimating the expected maximum delay to get a response (default: 60 s)
 net: X3210 = 20 s	After L3 Complete, wait for MSC to confirm (default: 20 s)
 mgw: X2427 = 5 s	timeout for MGCP response from MGW (default: 5 s)