stats: Support regular stats flush

Reliable monitoring requires regular flush of all stat values, even
if they have not changed. Otherwise (1) the monitoring app has to
maintain state and (2) can go out of sync if it's restarted while
the app is still running.

Change-Id: I04f1e7bdf0d6f20e4f15571e94191de61c47ddad

1 files changed, 26 insertions, 0 deletions

diff --git a/src/vty/stats_vty.c b/src/vty/stats_vty.c
index a512703f..46282817 100644
--- a/src/vty/stats_vty.c
+++ b/src/vty/stats_vty.c
@@ -245,6 +245,27 @@ DEFUN(cfg_stats_reporter_disable, cfg_stats_reporter_disable_cmd,
 	return CMD_SUCCESS;
 }
 
+DEFUN(cfg_stats_reporter_flush_period, cfg_stats_reporter_flush_period_cmd,
+	"flush-period <0-65535>",
+	CFG_STATS_STR "Send all stats even if they have not changed (i.e. force the flush)"
+	              "every N-th reporting interval. Set to 0 to disable regular flush (default).\n"
+	"0 to disable regular flush (default), 1 to flush every time, 2 to flush every 2nd time, etc\n")
+{
+	int rc;
+	unsigned int period = atoi(argv[0]);
+	struct osmo_stats_reporter *srep = osmo_stats_vty2srep(vty);
+	OSMO_ASSERT(srep);
+
+	rc = osmo_stats_reporter_set_flush_period(srep, period);
+	if (rc < 0) {
+		vty_out(vty, "%% Unable to set force flush period: %s%s",
+			strerror(-rc), VTY_NEWLINE);
+		return CMD_WARNING;
+	}
+
+	return CMD_SUCCESS;
+}
+
 DEFUN(cfg_stats_reporter_statsd, cfg_stats_reporter_statsd_cmd,
 	"stats reporter statsd",
 	CFG_STATS_STR CFG_REPORTER_STR "Report to a STATSD server\n")
@@ -588,6 +609,10 @@ static int config_write_stats_reporter(struct vty *vty, struct osmo_stats_report
 	else
 		vty_out(vty, "  no prefix%s", VTY_NEWLINE);
 
+	if (srep->flush_period > 0)
+		vty_out(vty, "  flush-period %d%s",
+			srep->flush_period, VTY_NEWLINE);
+
 	if (srep->enabled)
 		vty_out(vty, "  enable%s", VTY_NEWLINE);
 
@@ -637,6 +662,7 @@ void osmo_stats_vty_add_cmds()
 	install_element(CFG_STATS_NODE, &cfg_stats_reporter_level_cmd);
 	install_element(CFG_STATS_NODE, &cfg_stats_reporter_enable_cmd);
 	install_element(CFG_STATS_NODE, &cfg_stats_reporter_disable_cmd);
+	install_element(CFG_STATS_NODE, &cfg_stats_reporter_flush_period_cmd);
 
 	install_element_ve(&show_stats_asciidoc_table_cmd);
 	install_element_ve(&show_rate_counters_cmd);