Add exponential average of responsetime to output

git-svn-id: svn+ssh://projects.linpro.no/svn/varnish/trunk@3103 d4fa192b-c00b-0410-8231-f00ffab90ce4

diff --git a/varnish-cache/bin/varnishd/cache_backend_poll.c b/varnish-cache/bin/varnishd/cache_backend_poll.c
index bfc5eaf9719fc3671e80e37b5fc5138ef6db7531..2d76a1d449824551a2be9c0629908d179bd239f2 100644 (file)
--- a/varnish-cache/bin/varnishd/cache_backend_poll.c
+++ b/varnish-cache/bin/varnishd/cache_backend_poll.c
@@ -54,6 +54,9 @@
 #include "vrt.h"
 #include "cache_backend.h"
 
+/* Default averaging rate, we want something pretty responsive */
+#define AVG_RATE                       4
+
 struct vbp_target {
        unsigned                        magic;
 #define VBP_TARGET_MAGIC               0x6b7cb656
@@ -71,6 +74,10 @@ struct vbp_target {
 #include "cache_backend_poll.h"
 #undef BITMAP
 
+       double                          last;
+       double                          avg;
+       double                          rate;
+
        VTAILQ_ENTRY(vbp_target)        list;
        pthread_t                       thread;
 };
@@ -205,6 +212,7 @@ vbp_poke(struct vbp_target *vt)
 
        TCP_close(&s);
        t_now = TIM_real();
+       vt->last = t_now - t_start;
        vt->good_recv |= 1;
        /* XXX: Check reponse status */
        vt->happy |= 1;
@@ -255,8 +263,16 @@ vbp_wrk_poll_backend(void *priv)
 #define BITMAP(n, c, t, b)     vt->n <<= 1;
 #include "cache_backend_poll.h"
 #undef BITMAP
+               vt->last = 0;
                vbp_poke(vt);
 
+               /* Calculate exponential average */
+               if (vt->happy & 1) {
+                       if (vt->rate < AVG_RATE)
+                               vt->rate += 1.0;
+                       vt->avg += (vt->last - vt->avg) / vt->rate;
+               }
+
                i = 0;
 #define BITMAP(n, c, t, b)     bits[i++] = (vt->n & 1) ? c : '-';
 #include "cache_backend_poll.h"
@@ -284,9 +300,10 @@ vbp_wrk_poll_backend(void *priv)
                                logmsg = "Still sick";
                        vt->backend->healthy = 0;
                }
-               VSL(SLT_Backend_health, 0, "%s %s %s %u %u %u",
+               VSL(SLT_Backend_health, 0, "%s %s %s %u %u %u %.6f %.6f",
                    vt->backend->vcl_name, logmsg, bits,
-                   vt->good, vt->probe.threshold, vt->probe.window);
+                   vt->good, vt->probe.threshold, vt->probe.window,
+                   vt->last, vt->avg);
                        
                if (!vt->stop)
                        dsleep(vt->probe.interval);
@@ -325,6 +342,7 @@ vbp_health_one(struct cli *cli, const struct vbp_target *vt)
            vt->backend->healthy ? "Healthy" : "Sick");
        cli_out(cli, "Current states  good: %2u threshold: %2u window: %2u\n",
            vt->good, vt->probe.threshold, vt->probe.window);
+       cli_out(cli, "Average responsetime of good probes: %.6f\n", vt->avg);
        cli_out(cli, 
            "Oldest                       "
            "                             Newest\n");