Only in zabbix-2.0.8/include: stamp-h1
diff -ruB zabbix-2.0.8/src/libs/zbxdbcache/dbcache.c zabbix-2.0.8-log/src/libs/zbxdbcache/dbcache.c
--- zabbix-2.0.8/src/libs/zbxdbcache/dbcache.c	2013-08-21 10:59:21.000000000 -0300
+++ zabbix-2.0.8-log/src/libs/zbxdbcache/dbcache.c	2013-08-22 21:39:31.694026394 -0300
@@ -2165,7 +2165,7 @@
 	static ZBX_DC_HISTORY	*history = NULL;
 	int			i, history_num, n, f;
 	int			syncs;
-	int			total_num = 0;
+	int			total_num = 0, flag_for1 = 0, flag_for2 = 0, flag_log = 0;
 	int			skipped_clock, max_delay;
 	time_t			now = 0;
 
@@ -2188,6 +2188,13 @@
 	syncs = cache->history_num / ZBX_SYNC_MAX;
 	max_delay = (int)time(NULL) - CONFIG_HISTSYNCER_FREQUENCY;
 
+	// Edit Unirede - Debug
+	if (cache->history_num > 10000) {
+		flag_log = 1;
+		zabbix_log(LOG_LEVEL_ERR, "In %s() history_first:%d history_num:%d syncs:%d max_delay:%d",
+			__function_name, cache->history_first, cache->history_num, syncs, max_delay);
+	}
+
 	do
 	{
 		LOCK_CACHE;
@@ -2199,6 +2206,8 @@
 		{
 			int	num;
 
+			flag_for1++;
+
 			if (ZBX_HISTORY_SIZE <= f)
 				f -= ZBX_HISTORY_SIZE;
 
@@ -2223,14 +2232,18 @@
 				if (SUCCEED == uint64_array_exists(cache->itemids, cache->itemids_num,
 						cache->history[f].itemid))
 				{
-					if (0 == skipped_clock)
+					if (0 == skipped_clock) {
 						skipped_clock = cache->history[f].clock;
+						zabbix_log(LOG_LEVEL_ERR, "In uint64_array_exists() num:%d itemid:" ZBX_FS_UI64, num, cache->history[f].itemid);
+					}
 					n -= num;
 					f += num;
 					continue;
 				}
-				else if (1 < num && 0 == skipped_clock)
+				else if (1 < num && 0 == skipped_clock) {
 					skipped_clock = cache->history[ZBX_HISTORY_SIZE == f + 1 ? 0 : f + 1].clock;
+					zabbix_log(LOG_LEVEL_ERR, "In else if() num:%d itemid:" ZBX_FS_UI64, num, cache->history[f].itemid);
+				}
 
 				uint64_array_add(&cache->itemids, &cache->itemids_alloc,
 						&cache->itemids_num, cache->history[f].itemid, 0);
@@ -2289,6 +2302,7 @@
 
 		for (n = cache->history_num; 0 < n; n--)
 		{
+			flag_for2++;
 			if (0 == f)
 				f = ZBX_HISTORY_SIZE;
 			f--;
@@ -2366,6 +2380,13 @@
 		}
 	}
 	while (--syncs > 0 || sync_type == ZBX_SYNC_FULL || (skipped_clock != 0 && skipped_clock < max_delay));
+
+	// Edit Unirede - Debug
+	if (flag_log) {
+		zabbix_log(LOG_LEVEL_ERR, "End %s() history_first:%d history_num:%d skipped_clock:%d syncs:%d max_delay:%d flag_for1:%d flag_for2:%d",
+			__function_name, cache->history_first, cache->history_num, skipped_clock, syncs, max_delay, flag_for1, flag_for2);
+	}
+
 finish:
 	if (ZBX_SYNC_FULL == sync_type)
 		zabbix_log(LOG_LEVEL_WARNING, "syncing history data done");
diff -ruB zabbix-2.0.8/src/zabbix_server/dbsyncer/dbsyncer.c zabbix-2.0.8-log/src/zabbix_server/dbsyncer/dbsyncer.c
--- zabbix-2.0.8/src/zabbix_server/dbsyncer/dbsyncer.c	2013-08-21 10:59:21.000000000 -0300
+++ zabbix-2.0.8-log/src/zabbix_server/dbsyncer/dbsyncer.c	2013-08-22 21:40:21.509752398 -0300
@@ -65,7 +65,7 @@
 		num = DCsync_history(ZBX_SYNC_PARTIAL);
 		sec = zbx_time() - sec;
 
-		zabbix_log(LOG_LEVEL_DEBUG, "%s #%d spent " ZBX_FS_DBL " seconds while processing %d items",
+		zabbix_log(LOG_LEVEL_ERR, "%s #%d spent " ZBX_FS_DBL " seconds while processing %d items",
 				get_process_type_string(process_type), process_num, sec, num);
 
 		if (-1 == last_sleeptime)