From d553c085e7fbe4b41234e821896e6e6bbcc1e201 Mon Sep 17 00:00:00 2001 From: Neels Hofmeyr Date: Wed, 6 Mar 2019 16:01:00 +0100 Subject: [PATCH] sms queue: avoid repeated Paging for a failed SMS So far, sms_pending_failed() starts a new sms_queue_trigger() run. The intention behind that might have been to fill up the queue when sending SMS has failed, but the practical effect is actually bad: As current ttcn3-msc-test runs show, a failed MT SMS gets triggered multiple times in short succession, i.e. osmo-msc repeatedly sends Paging Requests for the same subscriber. This special case happens actually only when there are few SMS still in the DB to be delivered. In the TTCN3 test, there is exactly one MT SMS for one subscriber, and retriggering the queue brings up the same SMS every time. See f_tc_lu_and_mt_sms_paging_and_nothing() and f_tc_sgsap_mt_sms_and_nothing() which say: "/* Expect the MSC to page exactly 10 times before giving up */" This is bad because an MSC should send a Paging Request exactly once. Retrying failed Paging is clearly the task of the BSC, not the MSC. The remaining code around Paging correctly follows this paradigm, but this retrigger doesn't. Do not immediately trigger the SMS queue on a failed MT SMS. Instead, leave it up to the periodical SMS queue trigger to decide. This patch will cause the MT SMS tests in ttcn3-msc-tests to fail, because the test expectations are bogus. The patch fixing the test run is listed 'Related' below. Related: I7dce12942a65eaaf97f78ca69401c7f93faacb9e (osmo-ttcn3-hacks) Change-Id: I24bf9f1c1167efe1080ae4cf47ed2ef0bd981e49 --- src/libmsc/sms_queue.c | 1 - 1 file changed, 1 deletion(-) diff --git a/src/libmsc/sms_queue.c b/src/libmsc/sms_queue.c index afd878f1c..4de30ad43 100644 --- a/src/libmsc/sms_queue.c +++ b/src/libmsc/sms_queue.c @@ -161,7 +161,6 @@ static void sms_pending_failed(struct gsm_sms_pending *pending, int paging_error sms_pending_free(pending); smsq->pending -= 1; - sms_queue_trigger(smsq); } /*