BUG/MINOR: server: update last_change on maint->ready transitions too

Nenad noticed that when leaving maintenance, the servers' last_change
field was not updated. This is visible in the Status column of the stats
page in front of the state, as the cumuled time spent in the current state
is wrong, it starts from the last transition (typically ready->maint). In
addition, the backend's state was not updated either, because the down
transition is performed by set_backend_down() which also emits a log, and
it is this function which was extended to update the backend's last_change,
but it's not called for down->up transitions so that was not done.

The most visible (and unpleasant) effect of this bug is that it affects
slowstart so such a server could immediately restart with a significant
load ratio.

This should likely be backported to all stable releases.

diff --git a/src/server.c b/src/server.c
index 22d0fff689acfea63bd1e3bbbe6f0d8bab444e39..c2c27a15ba50f14f77be8614c26f110bf956b5ed 100644 (file)
--- a/src/server.c
+++ b/src/server.c
@@ -5138,6 +5138,7 @@ static void srv_update_status(struct server *s)
                                s->next_state = SRV_ST_STOPPING;
                        }
                        else {
+                               s->last_change = now.tv_sec;
                                s->next_state = SRV_ST_STARTING;
                                if (s->slowstart > 0) {
                                        if (s->warmup)
@@ -5197,6 +5198,8 @@ static void srv_update_status(struct server *s)
 
                if (prev_srv_count && s->proxy->srv_bck == 0 && s->proxy->srv_act == 0)
                        set_backend_down(s->proxy);
+               else if (!prev_srv_count && (s->proxy->srv_bck || s->proxy->srv_act))
+                       s->proxy->last_change = now.tv_sec;
 
                /* If the server is set with "on-marked-up shutdown-backup-sessions",
                 * and it's not a backup server and its effective weight is > 0,