modules/stats: expose frequent queries LRU turnover

diff --git a/modules/stats/stats.c b/modules/stats/stats.c
index 078ff7b12e135b4782fbe10d85b2765e35dd6f6b..a35cfd5e069ab8c6487490fff3385701046433e6 100644 (file)
--- a/modules/stats/stats.c
+++ b/modules/stats/stats.c
@@ -217,7 +217,7 @@ static char* stats_get(void *env, struct kr_module *module, const char *args)
        struct stat_data *data = module->data;
 
        /* Expecting CHAR_BIT to be 8, this is a safe bet */
-       char *ret = malloc(3 * sizeof(ret) + 2);
+       char *ret = malloc(3 * sizeof(size_t) + 2);
        if (!ret) {
                return NULL;
        }
@@ -305,6 +305,19 @@ static char* freq_list(void *env, struct kr_module *module, const char *args)
        return ret;
 }
 
+static char* freq_turnover(void *env, struct kr_module *module, const char *args)
+{
+       struct stat_data *data = module->data;
+       namehash_t *freq_table = data->frequent.names;
+       if (!freq_table) {
+               return NULL;
+       }
+       JsonNode *root = json_mknumber(freq_table->evictions);
+       char *ret = json_encode(root);
+       json_delete(root);
+       return ret;
+}
+
 static char* freq_clear(void *env, struct kr_module *module, const char *args)
 {
        struct stat_data *data = module->data;
@@ -367,6 +380,7 @@ struct kr_prop *stats_props(void)
            { &stats_list,    "list", "List observed metrics.", },
            { &freq_list,     "queries", "List most frequent queries.", },
            { &freq_clear,    "queries_clear", "Clear most frequent queries.", },
+           { &freq_turnover, "queries_turnover", "Turnover of the frequent queries.", },
            { NULL, NULL, NULL }
        };
        return prop_list;