stats plugin: Optimized to lookup statistics only when necessary.

diff --git a/src/plugins/stats/stats-plugin.c b/src/plugins/stats/stats-plugin.c
index 10b67a9445b0308fab767b51906c8e232fd24426..43bd3bdd88ad572ee4b0b5a37fa1694c4fe7bc7e 100644 (file)
--- a/src/plugins/stats/stats-plugin.c
+++ b/src/plugins/stats/stats-plugin.c
@@ -17,7 +17,7 @@
        MODULE_CONTEXT(obj, stats_storage_module)
 
 /* Refresh session every 10 seconds, if anything has changed */
-#define SESSION_STATS_REFRESH_MSECS (10*1000)
+#define SESSION_STATS_REFRESH_SECS 10
 /* If session isn't refreshed every 15 minutes, it's dropped.
    Must be smaller than MAIL_SESSION_IDLE_TIMEOUT_MSECS in stats server */
 #define SESSION_STATS_FORCE_REFRESH_SECS (5*60)
@@ -46,6 +46,8 @@ static MODULE_CONTEXT_DEFINE_INIT(stats_storage_module,
                                  &mail_storage_module_register);
 
 static struct stats_connection *global_stats_conn = NULL;
+static struct mail_user *stats_global_user = NULL;
+static unsigned int stats_user_count = 0;
 
 static int
 process_io_buffer_parse(const char *buf, uint64_t *read_bytes_r,
@@ -249,7 +251,16 @@ static void stats_io_activate(void *context)
        struct mail_user *user = context;
        struct stats_user *suser = STATS_USER_CONTEXT(user);
 
-       mail_stats_get(suser, &suser->pre_io_stats);
+       if (stats_user_count == 1) {
+               /* the first user sets the global user. the second user sets
+                  it to NULL. when we get back to one user we'll need to set
+                  the global user again somewhere. do it here. */
+               stats_global_user = user;
+       } else {
+               i_assert(stats_global_user == NULL);
+
+               mail_stats_get(suser, &suser->pre_io_stats);
+       }
 }
 
 static void timeval_add_diff(struct timeval *dest,
@@ -311,15 +322,15 @@ void mail_stats_export(string_t *str, const struct mail_stats *stats)
        str_printfa(str, "\tcache=%lu", tstats->cache_hit_count);
 }
 
-static void stats_io_deactivate(void *context)
+static void stats_add_session(struct mail_user *user)
 {
-       struct mail_user *user = context;
        struct stats_user *suser = STATS_USER_CONTEXT(user);
        struct mail_stats new_stats;
 
        mail_stats_get(suser, &new_stats);
        mail_stats_add_diff(&suser->session_stats, &suser->pre_io_stats,
                            &new_stats);
+       suser->pre_io_stats = new_stats;
 }
 
 static bool session_stats_need_send(struct stats_user *suser)
@@ -342,6 +353,36 @@ static void session_stats_refresh(struct mail_user *user)
                stats_connection_send_session(suser->stats_conn, user,
                                              &suser->session_stats);
        }
+       if (suser->to_stats_timeout != NULL)
+               timeout_remove(&suser->to_stats_timeout);
+}
+
+static void session_stats_refresh_timeout(struct mail_user *user)
+{
+       if (stats_global_user != NULL)
+               stats_add_session(user);
+       session_stats_refresh(user);
+}
+
+static void stats_io_deactivate(void *context)
+{
+       struct mail_user *user = context;
+       struct stats_user *suser = STATS_USER_CONTEXT(user);
+       unsigned int last_update_secs;
+
+       if (stats_global_user == NULL)
+               stats_add_session(user);
+
+       last_update_secs = ioloop_time - suser->last_session_update;
+       if (last_update_secs >= SESSION_STATS_REFRESH_SECS) {
+               if (stats_global_user != NULL)
+                       stats_add_session(user);
+               session_stats_refresh(user);
+       } else if (suser->to_stats_timeout == NULL) {
+               suser->to_stats_timeout =
+                       timeout_add(SESSION_STATS_REFRESH_SECS*1000,
+                                   session_stats_refresh_timeout, user);
+       }
 }
 
 static void stats_user_deinit(struct mail_user *user)
@@ -349,6 +390,16 @@ static void stats_user_deinit(struct mail_user *user)
        struct stats_user *suser = STATS_USER_CONTEXT(user);
        struct stats_connection *stats_conn = suser->stats_conn;
 
+       i_assert(stats_user_count > 0);
+       if (--stats_user_count == 0) {
+               /* we were updating the session lazily. do one final update. */
+               i_assert(stats_global_user == user);
+               stats_add_session(user);
+               stats_global_user = NULL;
+       } else {
+               i_assert(stats_global_user == NULL);
+       }
+
        io_loop_context_remove_callbacks(suser->ioloop_ctx,
                                         stats_io_activate,
                                         stats_io_deactivate, user);
@@ -356,7 +407,8 @@ static void stats_user_deinit(struct mail_user *user)
        session_stats_refresh(user);
        stats_connection_disconnect(stats_conn, user);
 
-       timeout_remove(&suser->to_stats_timeout);
+       if (suser->to_stats_timeout != NULL)
+               timeout_remove(&suser->to_stats_timeout);
        suser->module_ctx.super.deinit(user);
 
        stats_connection_unref(&stats_conn);
@@ -388,6 +440,17 @@ static void stats_user_created(struct mail_user *user)
        }
        stats_connection_ref(global_stats_conn);
 
+       if (stats_user_count == 0) {
+               /* first user connection */
+               stats_global_user = user;
+       } else if (stats_user_count == 1) {
+               /* second user connection. we'll need to start doing
+                  per-io callback tracking now. */
+               stats_add_session(stats_global_user);
+               stats_global_user = NULL;
+       }
+       stats_user_count++;
+
        suser = p_new(user->pool, struct stats_user, 1);
        suser->module_ctx.super = *v;
        user->vlast = &suser->module_ctx.super;
@@ -396,8 +459,6 @@ static void stats_user_created(struct mail_user *user)
        suser->stats_conn = global_stats_conn;
        guid_128_generate(suser->session_guid);
        suser->last_session_update = ioloop_time;
-       suser->to_stats_timeout = timeout_add(SESSION_STATS_REFRESH_MSECS,
-                                             session_stats_refresh, user);
 
        suser->ioloop_ctx = ioloop_ctx;
        io_loop_context_add_callbacks(ioloop_ctx,