MINOR: activity: indicate the number of calls on "show tasks"

The "show tasks" command can be useful to inspect run queues for active
tasks, but currently it's difficult to distinguish an occasional running
task from a heavily active one. Let's collect the number of calls for
each of them, report them average on the number of instances of each task
as well as a percentage of the total used. This way it even becomes
possible to get a hint about how CPU usage is distributed.

diff --git a/src/activity.c b/src/activity.c
index 8a306063a099b7d517440def8ffcb54d925ea298..1efd6281a154f4ff475420ffdb5f7faf4472a3a7 100644 (file)
--- a/src/activity.c
+++ b/src/activity.c
@@ -1296,7 +1296,7 @@ static int cli_io_handler_show_tasks(struct appctx *appctx)
        const struct task *t;
        uint64_t now_ns, lat;
        struct eb32_node *rqnode;
-       uint64_t tot_calls;
+       uint64_t tot_calls, tot_cpu;
        int thr, queue;
        int i, max;
 
@@ -1309,7 +1309,9 @@ static int cli_io_handler_show_tasks(struct appctx *appctx)
         * reflect the latency when set. We prefer to take the time before
         * calling thread_isolate() so that the wait time doesn't impact the
         * measurement accuracy. However this requires to take care of negative
-        * times since tasks might be queued after we retrieve it.
+        * times since tasks might be queued after we retrieve it. The cpu_time
+        * will store the total number of calls per task, allowing to sort out
+        * the most vs least busy ones.
         */
 
        now_ns = now_mono_time();
@@ -1331,6 +1333,7 @@ static int cli_io_handler_show_tasks(struct appctx *appctx)
                                if ((int64_t)lat > 0)
                                        entry->lat_time += lat;
                        }
+                       entry->cpu_time += t->calls;
                        entry->calls++;
                        rqnode = eb32_next(rqnode);
                }
@@ -1348,6 +1351,7 @@ static int cli_io_handler_show_tasks(struct appctx *appctx)
                                if ((int64_t)lat > 0)
                                        entry->lat_time += lat;
                        }
+                       entry->cpu_time += t->calls;
                        entry->calls++;
                        rqnode = eb32_next(rqnode);
                }
@@ -1361,6 +1365,7 @@ static int cli_io_handler_show_tasks(struct appctx *appctx)
                                if ((int64_t)lat > 0)
                                        entry->lat_time += lat;
                        }
+                       entry->cpu_time += t->calls;
                        entry->calls++;
                }
 
@@ -1374,6 +1379,7 @@ static int cli_io_handler_show_tasks(struct appctx *appctx)
                                        if ((int64_t)lat > 0)
                                                entry->lat_time += lat;
                                }
+                               entry->cpu_time += t->calls;
                                entry->calls++;
                        }
                }
@@ -1384,14 +1390,17 @@ static int cli_io_handler_show_tasks(struct appctx *appctx)
 
        chunk_reset(&trash);
 
-       tot_calls = 0;
-       for (i = 0; i < SCHED_ACT_HASH_BUCKETS; i++)
+       tot_calls = tot_cpu = 0;
+       for (i = 0; i < SCHED_ACT_HASH_BUCKETS; i++) {
                tot_calls += tmp_activity[i].calls;
+               tot_cpu += tmp_activity[i].cpu_time;
+       }
+       tot_cpu = tot_cpu ? tot_cpu : 1; // prepare for the divide
 
        qsort(tmp_activity, SCHED_ACT_HASH_BUCKETS, sizeof(tmp_activity[0]), cmp_sched_activity_calls);
 
        chunk_appendf(&trash, "Running tasks: %d (%d threads)\n"
-                     "  function                     places     %%    lat_tot   lat_avg\n",
+                     "  function                     places     %%    lat_tot   lat_avg  calls_tot  calls_avg calls%%\n",
                      (int)tot_calls, global.nbthread);
 
        for (i = 0; i < SCHED_ACT_HASH_BUCKETS && tmp_activity[i].calls; i++) {
@@ -1413,7 +1422,11 @@ static int cli_io_handler_show_tasks(struct appctx *appctx)
                              (int)(100ULL * tmp_activity[i].calls / tot_calls),
                              (int)((1000ULL * tmp_activity[i].calls / tot_calls)%10));
                print_time_short(&trash, "   ", tmp_activity[i].lat_time, "");
-               print_time_short(&trash, "   ", tmp_activity[i].lat_time / tmp_activity[i].calls, "\n");
+               print_time_short(&trash, "   ", tmp_activity[i].lat_time / tmp_activity[i].calls, "");
+               chunk_appendf(&trash, " %10llu %10llu  %3d.%1d\n",
+                             (ullong)tmp_activity[i].cpu_time, (ullong)tmp_activity[i].cpu_time / tmp_activity[i].calls,
+                             (int)(100ULL * tmp_activity[i].cpu_time / tot_cpu),
+                             (int)((1000ULL * tmp_activity[i].cpu_time / tot_cpu)%10));
        }
 
        if (applet_putchk(appctx, &trash) == -1) {