From ed54cf5eeee34d5b240986941fddd2034b734a1b Mon Sep 17 00:00:00 2001
From: Donald Buczek <buczek@molgen.mpg.de>
Date: Thu, 6 Jul 2017 10:26:54 +0200
Subject: [PATCH] mxqd: Refactor main loop

The server status if multiple times set from the main loop to
IDLE,RUNNING,BACKFILL,CPUOPTIMAL or FULL based on server->slots_running,
server->slots, server->threads_running.

Factor this out into a separate function to avoid repetition.

Add a call to this function before the main loop so that we immediately
get a correct status after a server start.

Simplify the loop code by setting server status at end of loop and avoid
the continue pattern. As a side effect this also resolves a bug, that
the server status was not updated in a loop iteration where new jobs
were started.
---
 mxqd.c | 72 ++++++++++++++++++++++++++--------------------------------
 1 file changed, 32 insertions(+), 40 deletions(-)

diff --git a/mxqd.c b/mxqd.c
index 171bf159..8435e3bf 100644
--- a/mxqd.c
+++ b/mxqd.c
@@ -2325,6 +2325,25 @@ static void process_signal(struct mxq_server *server,int sig,int extra)
     }
 }
 
+static void update_status(struct mxq_server *server)
+{
+    struct mxq_daemon *daemon = &server->daemon;
+
+    if (!server->slots_running) {
+            mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_IDLE);
+    } else {
+        if (server->slots_running < server->slots)
+                mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_RUNNING);
+        else if (server->slots_running > server->slots)
+                mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_BACKFILL);
+        else
+            if (server->threads_running == server->slots)
+                mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_CPUOPTIMAL);
+            else
+                mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_FULL);
+    }
+}
+
 int main(int argc, char *argv[])
 {
     int group_cnt;
@@ -2411,6 +2430,7 @@ int main(int argc, char *argv[])
     if (server->recoveronly)
         fail = 1;
 
+    update_status(server);
     mx_log_info("entering main loop");
     while (!global_sigint_cnt && !global_sigterm_cnt && !global_sigquit_cnt && !global_sigrestart_cnt && !fail) {
         mx_log_debug("main loop - wait for signals max %ld sec",poll_interval.tv_sec);
@@ -2432,51 +2452,23 @@ int main(int argc, char *argv[])
         killall_over_time(server);
         killall_over_memory(server);
 
-        if (!server->group_cnt) {
-            assert(!server->jobs_running);
-            assert(!group_cnt);
-            mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_IDLE);
-            mx_log_debug("Nothing to do");
-            continue;
-        }
-
-        if (server->slots_running >= server->slots) {
-            if (server->threads_running == server->slots) {
-                mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_CPUOPTIMAL);
-            } else if (server->slots_running > server->slots) {
-                mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_BACKFILL);
-            } else {
-                mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_FULL);
-            }
-            mx_log_debug("All slots running");
-            continue;
-        }
-
-        slots_started=0;
-        do {
-            res = start_user_with_least_running_global_slot_count(server);
-            if (res>0) {
-                slots_started+=res;
-           }
-        } while (res>0);
-        if (slots_started)
-            mx_log_info("Main loop started %lu slots.", slots_started);
-        if (res<0) {
+        if (server->slots_running<server->slots && server->group_cnt) {
+            slots_started=0;
+            do {
+                res = start_user_with_least_running_global_slot_count(server);
+                if (res>0) {
+                    slots_started+=res;
+                }
+            } while (res>0);
+            if (slots_started)
+                mx_log_info("Main loop started %lu slots.", slots_started);
+            if (res<0) {
                 mx_log_info("No more slots started because we have users waiting for free slots");
                 mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_WAITING);
                 continue;
-        }
-
-        if (!slots_started && !slots_returned && !global_sigint_cnt && !global_sigterm_cnt) {
-            if (!server->jobs_running) {
-                mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_IDLE);
-                mx_log_debug("Tried Hard and nobody is doing anything.");
-            } else {
-                mxq_daemon_set_status(server->mysql, daemon, MXQ_DAEMON_STATUS_RUNNING);
-                mx_log_debug("Tried Hard. But have done nothing.");
             }
-            continue;
         }
+        update_status(server);
     }
     /*** clean up ***/