MINOR: log: report the number of dropped logs in the stats

It's easy to detect when logs on some paths are lost as sendmsg() will
return EAGAIN. This is particularly true when sending to /dev/log, which
often doesn't support a big logging capacity. Let's keep track of these
and report the total number of dropped messages in "show info".

diff --git a/include/proto/log.h b/include/proto/log.h
index b994470dd268c1a1c866dfd95d5c8312b20bcc0b..30d4dce7fb977b72ee75a3e26b499994cc62fa53 100644 (file)
--- a/include/proto/log.h
+++ b/include/proto/log.h
@@ -46,6 +46,8 @@ extern char clf_http_log_format[];
 
 extern char default_rfc5424_sd_log_format[];
 
+extern unsigned int dropped_logs;
+
 extern THREAD_LOCAL char *logheader;
 extern THREAD_LOCAL char *logheader_rfc5424;
 extern THREAD_LOCAL char *logline;

diff --git a/include/types/stats.h b/include/types/stats.h
index 2cb23bfdc5aa28b59354e4df87afec1f6d9545bc..75250447ec2d597290f5a1a0c9475746b2820cfd 100644 (file)
--- a/include/types/stats.h
+++ b/include/types/stats.h
@@ -293,6 +293,7 @@ enum info_field {
        INF_LISTENERS,
        INF_ACTIVE_PEERS,
        INF_CONNECTED_PEERS,
+       INF_DROPPED_LOGS,
 
        /* must always be the last one */
        INF_TOTAL_FIELDS

diff --git a/src/log.c b/src/log.c
index 24e4c3ff0248b7d3e2fc44bf7375aeb532d63380..3434550a387cfbda2b1ff99907911f43eb4443ef 100644 (file)
--- a/src/log.c
+++ b/src/log.c
@@ -210,6 +210,9 @@ char *log_format = NULL;
  */
 char default_rfc5424_sd_log_format[] = "- ";
 
+/* total number of dropped logs */
+unsigned int dropped_logs = 0;
+
 /* This is a global syslog header, common to all outgoing messages in
  * RFC3164 format. It begins with time-based part and is updated by
  * update_log_hdr().
@@ -1478,7 +1481,9 @@ send:
                if (sent < 0) {
                        static char once;
 
-                       if (!once) {
+                       if (errno == EAGAIN)
+                               HA_ATOMIC_ADD(&dropped_logs, 1);
+                       else if (!once) {
                                once = 1; /* note: no need for atomic ops here */
                                ha_alert("sendmsg() failed in logger #%d: %s (errno=%d)\n",
                                         nblogger, strerror(errno), errno);

diff --git a/src/stats.c b/src/stats.c
index 78342cde7f0665442ab85d414326b078fe3d5802..07a5ef74ea61d0e9a7604d2e83feb903038ec132 100644 (file)
--- a/src/stats.c
+++ b/src/stats.c
@@ -135,6 +135,7 @@ const char *info_field_names[INF_TOTAL_FIELDS] = {
        [INF_LISTENERS]                      = "Listeners",
        [INF_ACTIVE_PEERS]                   = "ActivePeers",
        [INF_CONNECTED_PEERS]                = "ConnectedPeers",
+       [INF_DROPPED_LOGS]                   = "DroppedLogs",
 };
 
 const char *stat_field_names[ST_F_TOTAL_FIELDS] = {
@@ -3302,6 +3303,7 @@ int stats_fill_info(struct field *info, int len)
        info[INF_LISTENERS]                      = mkf_u32(0, listeners);
        info[INF_ACTIVE_PEERS]                   = mkf_u32(0, active_peers);
        info[INF_CONNECTED_PEERS]                = mkf_u32(0, connected_peers);
+       info[INF_DROPPED_LOGS]                   = mkf_u32(0, dropped_logs);
 
        return 1;
 }