Merge remote-tracking branch 'github/master'

diff --git a/src/collectd.conf.in b/src/collectd.conf.in
index c9310ee..7c9860f 100644 (file)
--- a/src/collectd.conf.in
+++ b/src/collectd.conf.in
@@ -25,6 +25,13 @@
 #AutoLoadPlugin false
 
 #----------------------------------------------------------------------------#
+# When enabled, internal statistics are collected, using "collectd" as the   #
+# plugin name.                                                               #
+# Disabled by default.                                                       #
+#----------------------------------------------------------------------------#
+#CollectInternalStats false
+
+#----------------------------------------------------------------------------#
 # Interval at which to query values. This may be overwritten on a per-plugin #
 # base by using the 'Interval' option of the LoadPlugin block:               #
 #   <LoadPlugin foo>                                                         #

diff --git a/src/collectd.conf.pod b/src/collectd.conf.pod
index d38c5c9..cabbb52 100644 (file)
--- a/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@ -146,6 +146,18 @@ B<E<lt>PluginE<nbsp>...E<gt>> block acts as if it was immediately preceded by a
 B<LoadPlugin> statement. B<LoadPlugin> statements are still required for
 plugins that don't provide any configuration, e.g. the I<Load plugin>.
 
+=item B<CollectInternalStats> B<false>|B<true>
+
+When set to B<true>, various statistics about the I<collectd> daemon will be
+collected, with "collectd" as the I<plugin name>. Defaults to B<false>.
+
+The "write_queue" I<plugin instance> reports the number of elements currently
+queued and the number of elements dropped off the queue by the
+B<WriteQueueLimitLow>/B<WriteQueueLimitHigh> mechanism.
+
+The "cache" I<plugin instance> reports the number of elements in the value list
+cache (the cache you can interact with using L<collectd-unixsock(5)>).
+
 =item B<Include> I<Path> [I<pattern>]
 
 If I<Path> points to a file, includes that file. If I<Path> points to a
@@ -276,8 +288,11 @@ If B<WriteQueueLimitHigh> is set to non-zero and B<WriteQueueLimitLow> is
 unset, the latter will default to half of B<WriteQueueLimitHigh>.
 
 If you do not want to randomly drop values when the queue size is between
-I<LowNum> and I<HighNum>, set If B<WriteQueueLimitHigh> and
-B<WriteQueueLimitLow> to same value.
+I<LowNum> and I<HighNum>, set B<WriteQueueLimitHigh> and B<WriteQueueLimitLow>
+to the same value.
+
+Enabling the B<CollectInternalStats> option is of great help to figure out the
+values to set B<WriteQueueLimitHigh> and B<WriteQueueLimitLow> to.
 
 =item B<Hostname> I<Name>
 

diff --git a/src/configfile.c b/src/configfile.c
index 9a5807c..9841efd 100644 (file)
--- a/src/configfile.c
+++ b/src/configfile.c
@@ -117,6 +117,7 @@ static cf_global_option_t cf_global_options[] =
        {"WriteQueueLimitLow", NULL, NULL},
        {"Timeout",     NULL, "2"},
        {"AutoLoadPlugin", NULL, "false"},
+       {"CollectInternalStats", NULL, "false"},
        {"PreCacheChain",  NULL, "PreCache"},
        {"PostCacheChain", NULL, "PostCache"},
        {"MaxReadInterval", NULL, "86400"}

diff --git a/src/plugin.c b/src/plugin.c
index 5b9763a..cd99204 100644 (file)
--- a/src/plugin.c
+++ b/src/plugin.c
@@ -131,6 +131,9 @@ static _Bool           plugin_ctx_key_initialized = 0;
 static long            write_limit_high = 0;
 static long            write_limit_low = 0;
 
+static derive_t        stats_values_dropped = 0;
+static _Bool           record_statistics = 0;
+
 /*
  * Static functions
  */
@@ -144,6 +147,52 @@ static const char *plugin_get_dir (void)
                return (plugindir);
 }
 
+static void plugin_update_internal_statistics (void) { /* {{{ */
+       derive_t copy_write_queue_length;
+       value_list_t vl = VALUE_LIST_INIT;
+       value_t values[2];
+
+       copy_write_queue_length = write_queue_length;
+
+       /* Initialize `vl' */
+       vl.values = values;
+       vl.values_len = 2;
+       vl.time = 0;
+       sstrncpy (vl.host, hostname_g, sizeof (vl.host));
+       sstrncpy (vl.plugin, "collectd", sizeof (vl.plugin));
+
+       vl.type_instance[0] = 0;
+       vl.values_len = 1;
+
+       /* Write queue */
+       sstrncpy (vl.plugin_instance, "write_queue",
+                       sizeof (vl.plugin_instance));
+
+       /* Write queue : queue length */
+       vl.values[0].gauge = (gauge_t) copy_write_queue_length;
+       sstrncpy (vl.type, "queue_length", sizeof (vl.type));
+       vl.type_instance[0] = 0;
+       plugin_dispatch_values (&vl);
+
+       /* Write queue : Values dropped (queue length > low limit) */
+       vl.values[0].derive = (derive_t) stats_values_dropped;
+       sstrncpy (vl.type, "derive", sizeof (vl.type));
+       sstrncpy (vl.type_instance, "dropped", sizeof (vl.type_instance));
+       plugin_dispatch_values (&vl);
+
+       /* Cache */
+       sstrncpy (vl.plugin_instance, "cache",
+                       sizeof (vl.plugin_instance));
+
+       /* Cache : Nb entry in cache tree */
+       vl.values[0].gauge = (gauge_t) uc_get_size();
+       sstrncpy (vl.type, "cache_size", sizeof (vl.type));
+       vl.type_instance[0] = 0;
+       plugin_dispatch_values (&vl);
+
+       return;
+} /* }}} void plugin_update_internal_statistics */
+
 static void destroy_callback (callback_func_t *cf) /* {{{ */
 {
        if (cf == NULL)
@@ -1472,6 +1521,9 @@ void plugin_init_all (void)
        /* Init the value cache */
        uc_init ();
 
+       if (IS_TRUE (global_option_get ("CollectInternalStats")))
+               record_statistics = 1;
+
        chain_name = global_option_get ("PreCacheChain");
        pre_cache_chain = fc_chain_get_by_name (chain_name);
 
@@ -1564,6 +1616,9 @@ void plugin_init_all (void)
 /* TODO: Rename this function. */
 void plugin_read_all (void)
 {
+       if(record_statistics) {
+               plugin_update_internal_statistics ();
+       }
        uc_check_timeout ();
 
        return;
@@ -2085,9 +2140,16 @@ static _Bool check_drop_value (void) /* {{{ */
 int plugin_dispatch_values (value_list_t const *vl)
 {
        int status;
+       static pthread_mutex_t statistics_lock = PTHREAD_MUTEX_INITIALIZER;
 
-       if (check_drop_value ())
+       if (check_drop_value ()) {
+               if(record_statistics) {
+                       pthread_mutex_lock(&statistics_lock);
+                       stats_values_dropped++;
+                       pthread_mutex_unlock(&statistics_lock);
+               }
                return (0);
+       }
 
        status = plugin_write_enqueue (vl);
        if (status != 0)

diff --git a/src/utils_cache.c b/src/utils_cache.c
index 9d86781..fe22f21 100644 (file)
--- a/src/utils_cache.c
+++ b/src/utils_cache.c
@@ -570,6 +570,16 @@ gauge_t *uc_get_rate (const data_set_t *ds, const value_list_t *vl)
   return (ret);
 } /* gauge_t *uc_get_rate */
 
+size_t uc_get_size() {
+  size_t size_arrays = 0;
+
+  pthread_mutex_lock (&cache_lock);
+  size_arrays = (size_t) c_avl_size (cache_tree);
+  pthread_mutex_unlock (&cache_lock);
+
+  return (size_arrays);
+}
+
 int uc_get_names (char ***ret_names, cdtime_t **ret_times, size_t *ret_number)
 {
   c_avl_iterator_t *iter;

diff --git a/src/utils_cache.h b/src/utils_cache.h
index 16039aa..ea3eb2f 100644 (file)
--- a/src/utils_cache.h
+++ b/src/utils_cache.h
@@ -40,6 +40,7 @@ int uc_update (const data_set_t *ds, const value_list_t *vl);
 int uc_get_rate_by_name (const char *name, gauge_t **ret_values, size_t *ret_values_num);
 gauge_t *uc_get_rate (const data_set_t *ds, const value_list_t *vl);
 
+size_t uc_get_size();
 int uc_get_names (char ***ret_names, cdtime_t **ret_times, size_t *ret_number);
 
 int uc_get_state (const data_set_t *ds, const value_list_t *vl);