MINOR: contrib/prometheus-exporter: report the number of idle conns per server

This adds two extra metrics per server, one for the current number of idle
connections and one for the configured limit :

 * haproxy_server_idle_connections_current
 * haproxy_server_idle_connections_limit

diff --git a/contrib/prometheus-exporter/README b/contrib/prometheus-exporter/README
index b6160b38ea85a60e46bc461320b37c1d8e31bdfc..915fc7f54636fe109cf19797f173f14d4df8a112 100644 (file)
--- a/contrib/prometheus-exporter/README
+++ b/contrib/prometheus-exporter/README
@@ -243,4 +243,6 @@ Exported metrics
 | haproxy_server_current_throttle                    | Current throttle percentage for the server, when slowstart is active.     |
 | haproxy_server_loadbalanced_total                  | Total number of times a service was selected.                             |
 | haproxy_server_http_responses_total                | Total number of HTTP responses.                                           |
+| haproxy_server_idle_connections_current            | Current number of idle connections available for reuse.                   |
+| haproxy_server_idle_connections_limit              | Limit on the number of available idle connections.                        |
 +----------------------------------------------------+---------------------------------------------------------------------------+

diff --git a/contrib/prometheus-exporter/service-prometheus.c b/contrib/prometheus-exporter/service-prometheus.c
index 7b9d92678e340e29f3006fae0c4309d97cbf5bdf..508e6b1fc956abce3113e2c0fb2413138e67405f 100644 (file)
--- a/contrib/prometheus-exporter/service-prometheus.c
+++ b/contrib/prometheus-exporter/service-prometheus.c
@@ -232,6 +232,8 @@ const int promex_front_metrics[ST_F_TOTAL_FIELDS] = {
        [ST_F_REUSE]          = 0,
        [ST_F_CACHE_LOOKUPS]  = ST_F_CACHE_HITS,
        [ST_F_CACHE_HITS]     = ST_F_COMP_IN,
+       [ST_F_SRV_ICUR]       = 0,
+       [ST_F_SRV_ILIM]       = 0,
        [ST_F_QT_MAX]         = 0,
        [ST_F_CT_MAX]         = 0,
        [ST_F_RT_MAX]         = 0,
@@ -329,6 +331,8 @@ const int promex_back_metrics[ST_F_TOTAL_FIELDS] = {
        [ST_F_REUSE]          = ST_F_BIN,
        [ST_F_CACHE_LOOKUPS]  = ST_F_CACHE_HITS,
        [ST_F_CACHE_HITS]     = ST_F_COMP_IN,
+       [ST_F_SRV_ICUR]       = 0,
+       [ST_F_SRV_ILIM]       = 0,
        [ST_F_QT_MAX]         = ST_F_CT_MAX,
        [ST_F_CT_MAX]         = ST_F_RT_MAX,
        [ST_F_RT_MAX]         = ST_F_TT_MAX,
@@ -382,7 +386,7 @@ const int promex_srv_metrics[ST_F_TOTAL_FIELDS] = {
        [ST_F_HRSP_3XX]       = ST_F_HRSP_4XX,
        [ST_F_HRSP_4XX]       = ST_F_HRSP_5XX,
        [ST_F_HRSP_5XX]       = ST_F_HRSP_OTHER,
-       [ST_F_HRSP_OTHER]     = 0,
+       [ST_F_HRSP_OTHER]     = ST_F_SRV_ICUR,
        [ST_F_HANAFAIL]       = 0,
        [ST_F_REQ_RATE]       = 0,
        [ST_F_REQ_RATE_MAX]   = 0,
@@ -426,6 +430,8 @@ const int promex_srv_metrics[ST_F_TOTAL_FIELDS] = {
        [ST_F_REUSE]          = ST_F_DRESP,
        [ST_F_CACHE_LOOKUPS]  = 0,
        [ST_F_CACHE_HITS]     = 0,
+       [ST_F_SRV_ICUR]       = ST_F_SRV_ILIM,
+       [ST_F_SRV_ILIM]       = 0,
        [ST_F_QT_MAX]         = ST_F_CT_MAX,
        [ST_F_CT_MAX]         = ST_F_RT_MAX,
        [ST_F_RT_MAX]         = ST_F_TT_MAX,
@@ -586,6 +592,8 @@ const struct ist promex_st_metric_names[ST_F_TOTAL_FIELDS] = {
        [ST_F_REUSE]          = IST("connection_reuses_total"),
        [ST_F_CACHE_LOOKUPS]  = IST("http_cache_lookups_total"),
        [ST_F_CACHE_HITS]     = IST("http_cache_hits_total"),
+       [ST_F_SRV_ICUR]       = IST("server_idle_connections_current"),
+       [ST_F_SRV_ILIM]       = IST("server_idle_connections_limit"),
        [ST_F_QT_MAX]         = IST("max_queue_time_seconds"),
        [ST_F_CT_MAX]         = IST("max_connect_time_seconds"),
        [ST_F_RT_MAX]         = IST("max_response_time_seconds"),
@@ -746,6 +754,8 @@ const struct ist promex_st_metric_desc[ST_F_TOTAL_FIELDS] = {
        [ST_F_REUSE]          = IST("Total number of connection reuses."),
        [ST_F_CACHE_LOOKUPS]  = IST("Total number of HTTP cache lookups."),
        [ST_F_CACHE_HITS]     = IST("Total number of HTTP cache hits."),
+       [ST_F_SRV_ICUR]       = IST("Current number of idle connections available for reuse"),
+       [ST_F_SRV_ILIM]       = IST("Limit on the number of available idle connections"),
        [ST_F_QT_MAX]         = IST("Maximum observed time spent in the queue"),
        [ST_F_CT_MAX]         = IST("Maximum observed time spent waiting for a connection to complete"),
        [ST_F_RT_MAX]         = IST("Maximum observed time spent waiting for a server response"),
@@ -1062,6 +1072,8 @@ const struct ist promex_st_metric_types[ST_F_TOTAL_FIELDS] = {
        [ST_F_REUSE]          = IST("counter"),
        [ST_F_CACHE_LOOKUPS]  = IST("counter"),
        [ST_F_CACHE_HITS]     = IST("counter"),
+       [ST_F_SRV_ICUR]       = IST("gauge"),
+       [ST_F_SRV_ILIM]       = IST("gauge"),
        [ST_F_QT_MAX]         = IST("gauge"),
        [ST_F_CT_MAX]         = IST("gauge"),
        [ST_F_RT_MAX]         = IST("gauge"),
@@ -2043,6 +2055,12 @@ static int promex_dump_srv_metrics(struct appctx *appctx, struct htx *htx)
                                                appctx->ctx.stats.flags &= ~PROMEX_FL_METRIC_HDR;
                                                metric = mkf_u64(FN_COUNTER, sv->counters.p.http.rsp[0]);
                                                break;
+                                       case ST_F_SRV_ICUR:
+                                               metric = mkf_u32(0, sv->curr_idle_conns);
+                                               break;
+                                       case ST_F_SRV_ILIM:
+                                               metric = mkf_u32(FO_CONFIG|FN_LIMIT, (sv->max_idle_conns == -1) ? 0 : sv->max_idle_conns);
+                                               break;
 
                                        default:
                                                goto next_metric;