(no commit message)
[oweals/gnunet.git] / src / datastore / datastore_api.c
index a15bc183ac1b3a475af68fa6e24631b1435111d2..4172b5c9983583b7d258ff54d95e769deffab144 100644 (file)
 #include "gnunet_arm_service.h"
 #include "gnunet_constants.h"
 #include "gnunet_datastore_service.h"
+#include "gnunet_statistics_service.h"
 #include "datastore.h"
 
+/**
+ * If a client stopped asking for more results, how many more do
+ * we receive from the DB before killing the connection?  Trade-off
+ * between re-doing TCP handshakes and (needlessly) receiving 
+ * useless results.
+ */
+#define MAX_EXCESS_RESULTS 8
 
 /**
  * Context for processing status messages.
@@ -159,7 +167,7 @@ struct GNUNET_DATASTORE_QueueEntry
    * multiple of 64 bits.
    */
   int32_t was_transmitted;
-
+  
 };
 
 /**
@@ -183,6 +191,11 @@ struct GNUNET_DATASTORE_Handle
    */
   struct GNUNET_CLIENT_Connection *client;
 
+  /**
+   * Handle for statistics.
+   */
+  struct GNUNET_STATISTICS_Handle *stats;
+
   /**
    * Current transmit handle.
    */
@@ -214,6 +227,13 @@ struct GNUNET_DATASTORE_Handle
    */
   unsigned int queue_size;
 
+  /**
+   * Number of results we're receiving for the current query
+   * after application stopped to care.  Used to determine when
+   * to reset the connection.
+   */
+  unsigned int result_count;
+
   /**
    * Are we currently trying to receive from the service?
    */
@@ -249,6 +269,9 @@ GNUNET_DATASTORE_connect (const struct
   h->client = c;
   h->cfg = cfg;
   h->sched = sched;
+  h->stats = GNUNET_STATISTICS_create (sched,
+                                      "datastore-api", 
+                                      cfg);
   return h;
 }
 
@@ -330,6 +353,8 @@ void GNUNET_DATASTORE_disconnect (struct GNUNET_DATASTORE_Handle *h,
        }
       GNUNET_break (0);
     }
+  GNUNET_STATISTICS_destroy (h->stats,
+                            GNUNET_NO);
   GNUNET_free (h);
 }
 
@@ -346,6 +371,10 @@ timeout_queue_entry (void *cls,
 {
   struct GNUNET_DATASTORE_QueueEntry *qe = cls;
 
+  GNUNET_STATISTICS_update (qe->h->stats,
+                           gettext_noop ("# queue entry timeouts"),
+                           1,
+                           GNUNET_NO);
   qe->task = GNUNET_SCHEDULER_NO_TASK;
   GNUNET_assert (qe->was_transmitted == GNUNET_NO);
   qe->response_proc (qe, NULL);
@@ -412,6 +441,10 @@ make_queue_entry (struct GNUNET_DATASTORE_Handle *h,
        pos = h->queue_head;
     }
   c++;
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# queue entries created"),
+                           1,
+                           GNUNET_NO);
   GNUNET_CONTAINER_DLL_insert_after (h->queue_head,
                                     h->queue_tail,
                                     pos,
@@ -419,6 +452,10 @@ make_queue_entry (struct GNUNET_DATASTORE_Handle *h,
   h->queue_size++;
   if (c > max_queue_size)
     {
+      GNUNET_STATISTICS_update (h->stats,
+                               gettext_noop ("# queue overflows"),
+                               1,
+                               GNUNET_NO);
       response_proc (ret, NULL);
       return NULL;
     }
@@ -463,11 +500,11 @@ try_reconnect (void *cls,
 {
   struct GNUNET_DATASTORE_Handle *h = cls;
 
-  if (h->retry_time.value < GNUNET_CONSTANTS_SERVICE_RETRY.value)
+  if (h->retry_time.rel_value < GNUNET_CONSTANTS_SERVICE_RETRY.rel_value)
     h->retry_time = GNUNET_CONSTANTS_SERVICE_RETRY;
   else
     h->retry_time = GNUNET_TIME_relative_multiply (h->retry_time, 2);
-  if (h->retry_time.value > GNUNET_CONSTANTS_SERVICE_TIMEOUT.value)
+  if (h->retry_time.rel_value > GNUNET_CONSTANTS_SERVICE_TIMEOUT.rel_value)
     h->retry_time = GNUNET_CONSTANTS_SERVICE_TIMEOUT;
   h->reconnect_task = GNUNET_SCHEDULER_NO_TASK;
   h->client = GNUNET_CLIENT_connect (h->sched, "datastore", h->cfg);
@@ -477,6 +514,10 @@ try_reconnect (void *cls,
                  "DATASTORE reconnect failed (fatally)\n");
       return;
     }
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# datastore connections (re)created"),
+                           1,
+                           GNUNET_NO);
 #if DEBUG_DATASTORE
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Reconnected to DATASTORE\n");
@@ -541,6 +582,10 @@ transmit_request (void *cls,
     {
       GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
                  _("Failed to transmit request to DATASTORE.\n"));
+      GNUNET_STATISTICS_update (h->stats,
+                               gettext_noop ("# transmission request failures"),
+                               1,
+                               GNUNET_NO);
       do_disconnect (h);
       return 0;
     }
@@ -564,6 +609,10 @@ transmit_request (void *cls,
                         qe->response_proc,
                         qe,
                         GNUNET_TIME_absolute_get_remaining (qe->timeout));
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# bytes sent to datastore"),
+                           1,
+                           GNUNET_NO);
   return msize;
 }
 
@@ -684,9 +733,10 @@ process_status_message (void *cls,
       free_queue_entry (qe);
       if (NULL == h->client)
        return; /* forced disconnect */
-      rc.cont (rc.cont_cls, 
-              GNUNET_SYSERR,
-              _("Failed to receive response from database."));
+      if (rc.cont != NULL)
+       rc.cont (rc.cont_cls, 
+                GNUNET_SYSERR,
+                _("Failed to receive status response from database."));
       if (was_transmitted == GNUNET_YES)
        do_disconnect (h);
       return;
@@ -700,9 +750,10 @@ process_status_message (void *cls,
       GNUNET_break (0);
       h->retry_time = GNUNET_TIME_UNIT_ZERO;
       do_disconnect (h);
-      rc.cont (rc.cont_cls, 
-              GNUNET_SYSERR,
-              _("Error reading response from datastore service"));
+      if (rc.cont != NULL)
+       rc.cont (rc.cont_cls, 
+                GNUNET_SYSERR,
+                _("Error reading response from datastore service"));
       return;
     }
   sm = (const struct StatusMessage*) msg;
@@ -729,10 +780,16 @@ process_status_message (void *cls,
              (int) status,
              emsg);
 #endif
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# status messages received"),
+                           1,
+                           GNUNET_NO);
+  h->retry_time.rel_value = 0;
   process_queue (h);
-  rc.cont (rc.cont_cls, 
-          status,
-          emsg);
+  if (rc.cont != NULL)
+    rc.cont (rc.cont_cls, 
+            status,
+            emsg);
 }
 
 
@@ -796,7 +853,17 @@ GNUNET_DATASTORE_put (struct GNUNET_DATASTORE_Handle *h,
                         queue_priority, max_queue_size, timeout,
                         &process_status_message, &qc);
   if (qe == NULL)
-    return NULL;
+    {
+#if DEBUG_DATASTORE
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Could not create queue entry for PUT\n");
+#endif
+      return NULL;
+    }
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# PUT requests executed"),
+                           1,
+                           GNUNET_NO);
   dm = (struct DataMessage* ) &qe[1];
   dm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_PUT);
   dm->header.size = htons(msize);
@@ -861,7 +928,17 @@ GNUNET_DATASTORE_reserve (struct GNUNET_DATASTORE_Handle *h,
                         queue_priority, max_queue_size, timeout,
                         &process_status_message, &qc);
   if (qe == NULL)
-    return NULL;
+    {
+#if DEBUG_DATASTORE
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Could not create queue entry to reserve\n");
+#endif
+      return NULL;
+    }
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# RESERVE requests executed"),
+                           1,
+                           GNUNET_NO);
   rm = (struct ReserveMessage*) &qe[1];
   rm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_RESERVE);
   rm->header.size = htons(sizeof (struct ReserveMessage));
@@ -919,7 +996,17 @@ GNUNET_DATASTORE_release_reserve (struct GNUNET_DATASTORE_Handle *h,
                         queue_priority, max_queue_size, timeout,
                         &process_status_message, &qc);
   if (qe == NULL)
-    return NULL;
+    {
+#if DEBUG_DATASTORE
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Could not create queue entry to release reserve\n");
+#endif
+      return NULL;
+    }
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# RELEASE RESERVE requests executed"),
+                           1,
+                           GNUNET_NO);
   rrm = (struct ReleaseReserveMessage*) &qe[1];
   rrm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_RELEASE_RESERVE);
   rrm->header.size = htons(sizeof (struct ReleaseReserveMessage));
@@ -968,7 +1055,7 @@ GNUNET_DATASTORE_update (struct GNUNET_DATASTORE_Handle *h,
              "Asked to update entry %llu raising priority by %u and expiration to %llu\n",
              uid,
              (unsigned int) priority,
-             (unsigned long long) expiration.value);
+             (unsigned long long) expiration.abs_value);
 #endif
   qc.sc.cont = cont;
   qc.sc.cont_cls = cont_cls;
@@ -976,7 +1063,17 @@ GNUNET_DATASTORE_update (struct GNUNET_DATASTORE_Handle *h,
                         queue_priority, max_queue_size, timeout,
                         &process_status_message, &qc);
   if (qe == NULL)
-    return NULL;
+    {
+#if DEBUG_DATASTORE
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Could not create queue entry for UPDATE\n");
+#endif
+      return NULL;
+    }
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# UPDATE requests executed"),
+                           1,
+                           GNUNET_NO);
   um = (struct UpdateMessage*) &qe[1];
   um->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_UPDATE);
   um->header.size = htons(sizeof (struct UpdateMessage));
@@ -1041,7 +1138,17 @@ GNUNET_DATASTORE_remove (struct GNUNET_DATASTORE_Handle *h,
                         queue_priority, max_queue_size, timeout,
                         &process_status_message, &qc);
   if (qe == NULL)
-    return NULL;
+    {
+#if DEBUG_DATASTORE
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Could not create queue entry for REMOVE\n");
+#endif
+      return NULL;
+    }
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# REMOVE requests executed"),
+                           1,
+                           GNUNET_NO);
   dm = (struct DataMessage*) &qe[1];
   dm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_REMOVE);
   dm->header.size = htons(msize);
@@ -1087,6 +1194,13 @@ process_result_message (void *cls,
                      _("Failed to receive response from database.\n"));
          do_disconnect (h);
        }
+      else
+       {
+#if DEBUG_DATASTORE
+         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                     "Request dropped due to finite datastore queue length.\n");
+#endif
+       }
       if (rc.iter != NULL)
        rc.iter (rc.iter_cls,
                 NULL, 0, NULL, 0, 0, 0, 
@@ -1107,6 +1221,8 @@ process_result_message (void *cls,
        rc.iter (rc.iter_cls,
                 NULL, 0, NULL, 0, 0, 0, 
                 GNUNET_TIME_UNIT_ZERO_ABS, 0); 
+      h->retry_time.rel_value = 0;
+      h->result_count = 0;
       process_queue (h);
       return;
     }
@@ -1124,16 +1240,29 @@ process_result_message (void *cls,
                 GNUNET_TIME_UNIT_ZERO_ABS, 0); 
       return;
     }
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# Results received"),
+                           1,
+                           GNUNET_NO);
   if (rc.iter == NULL)
     {
-      /* abort iteration */
-#if DEBUG_DATASTORE
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                 "Aborting iteration via disconnect (client has cancelled)\n");
-#endif
-      free_queue_entry (qe);
-      h->retry_time = GNUNET_TIME_UNIT_ZERO;
-      do_disconnect (h);
+      h->result_count++;
+      GNUNET_STATISTICS_update (h->stats,
+                               gettext_noop ("# Excess results received"),
+                               1,
+                               GNUNET_NO);
+      if (h->result_count > MAX_EXCESS_RESULTS)
+       {
+         free_queue_entry (qe);
+         GNUNET_STATISTICS_update (h->stats,
+                                   gettext_noop ("# Forced database connection resets"),
+                                   1,
+                                   GNUNET_NO);
+         h->retry_time = GNUNET_TIME_UNIT_ZERO;
+         do_disconnect (h);      
+         return;
+       }
+      GNUNET_DATASTORE_get_next (h, GNUNET_NO);
       return;
     }
   dm = (const struct DataMessage*) msg;
@@ -1145,6 +1274,7 @@ process_result_message (void *cls,
              ntohl(dm->size),
              GNUNET_h2s(&dm->key));
 #endif
+  h->retry_time.rel_value = 0;
   rc.iter (rc.iter_cls,
           &dm->key,
           ntohl(dm->size),
@@ -1188,7 +1318,7 @@ GNUNET_DATASTORE_get_random (struct GNUNET_DATASTORE_Handle *h,
 #if DEBUG_DATASTORE
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Asked to get random entry in %llu ms\n",
-             (unsigned long long) timeout.value);
+             (unsigned long long) timeout.abs_value);
 #endif
   qc.rc.iter = iter;
   qc.rc.iter_cls = iter_cls;
@@ -1196,7 +1326,17 @@ GNUNET_DATASTORE_get_random (struct GNUNET_DATASTORE_Handle *h,
                         queue_priority, max_queue_size, timeout,
                         &process_result_message, &qc);
   if (qe == NULL)
-    return NULL;    
+    {
+#if DEBUG_DATASTORE
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Could not create queue entry for GET RANDOM\n");
+#endif
+      return NULL;    
+    }
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# GET RANDOM requests executed"),
+                           1,
+                           GNUNET_NO);
   m = (struct GNUNET_MessageHeader*) &qe[1];
   m->type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_GET_RANDOM);
   m->size = htons(sizeof (struct GNUNET_MessageHeader));
@@ -1238,7 +1378,7 @@ GNUNET_DATASTORE_get_zero_anonymity (struct GNUNET_DATASTORE_Handle *h,
 #if DEBUG_DATASTORE
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Asked to get zero-anonymity entry in %llu ms\n",
-             (unsigned long long) timeout.value);
+             (unsigned long long) timeout.abs_value);
 #endif
   qc.rc.iter = iter;
   qc.rc.iter_cls = iter_cls;
@@ -1246,9 +1386,19 @@ GNUNET_DATASTORE_get_zero_anonymity (struct GNUNET_DATASTORE_Handle *h,
                         queue_priority, max_queue_size, timeout,
                         &process_result_message, &qc);
   if (qe == NULL)
-    return NULL;    
+    {
+#if DEBUG_DATASTORE
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Could not create queue entry for zero-anonymity iteration\n");
+#endif
+      return NULL;    
+    }
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# GET ZERO ANONYMITY requests executed"),
+                           1,
+                           GNUNET_NO);
   m = (struct GetZeroAnonymityMessage*) &qe[1];
-  m->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_GET_RANDOM);
+  m->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_GET_ZERO_ANONYMITY);
   m->header.size = htons(sizeof (struct GetZeroAnonymityMessage));
   m->type = htonl ((uint32_t) type);
   process_queue (h);
@@ -1304,7 +1454,18 @@ GNUNET_DATASTORE_get (struct GNUNET_DATASTORE_Handle *h,
                         queue_priority, max_queue_size, timeout,
                         &process_result_message, &qc);
   if (qe == NULL)
-    return NULL;
+    {
+#if DEBUG_DATASTORE
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Could not queue request for `%s'\n",
+                 GNUNET_h2s (key));
+#endif
+      return NULL;
+    }
+  GNUNET_STATISTICS_update (h->stats,
+                           gettext_noop ("# GET requests executed"),
+                           1,
+                           GNUNET_NO);
   gm = (struct GetMessage*) &qe[1];
   gm->header.type = htons(GNUNET_MESSAGE_TYPE_DATASTORE_GET);
   gm->type = htonl(type);
@@ -1338,21 +1499,20 @@ GNUNET_DATASTORE_get_next (struct GNUNET_DATASTORE_Handle *h,
   struct ResultContext rc = qe->qc.rc;
 
   GNUNET_assert (&process_result_message == qe->response_proc);
-  if (GNUNET_YES == more)
-    {     
-      h->in_receive = GNUNET_YES;
-      GNUNET_CLIENT_receive (h->client,
-                            qe->response_proc,
-                            qe,
-                            GNUNET_TIME_absolute_get_remaining (qe->timeout));
-      return;
+  if (GNUNET_YES != more)
+    {
+      qe->qc.rc.iter = NULL;
+      qe->qc.rc.iter_cls = NULL;
+      if (rc.iter != NULL)
+       rc.iter (rc.iter_cls,
+                NULL, 0, NULL, 0, 0, 0, 
+                GNUNET_TIME_UNIT_ZERO_ABS, 0); 
     }
-  free_queue_entry (qe);
-  h->retry_time = GNUNET_TIME_UNIT_ZERO;
-  do_disconnect (h);
-  rc.iter (rc.iter_cls,
-          NULL, 0, NULL, 0, 0, 0, 
-          GNUNET_TIME_UNIT_ZERO_ABS, 0);       
+  h->in_receive = GNUNET_YES;
+  GNUNET_CLIENT_receive (h->client,
+                        qe->response_proc,
+                        qe,
+                        GNUNET_TIME_absolute_get_remaining (qe->timeout));
 }
 
 
@@ -1384,20 +1544,15 @@ GNUNET_DATASTORE_cancel (struct GNUNET_DATASTORE_QueueEntry *qe)
          qe->qc.rc.iter = NULL;    
          if (GNUNET_YES != h->in_receive)
            GNUNET_DATASTORE_get_next (h, GNUNET_YES);
-         return;
        }
-      reconnect = GNUNET_YES;
+      else
+       {
+         qe->qc.sc.cont = NULL;
+       }
+      return;
     }
   free_queue_entry (qe);
-  if (reconnect)
-    {
-      h->retry_time = GNUNET_TIME_UNIT_ZERO;
-      do_disconnect (h);
-    }
-  else
-    {
-      process_queue (h);
-    }
+  process_queue (h);
 }