==613== For counts of detected and suppressed errors, rerun with: -v
==613== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
==637==    at 0x4C30B06: calloc (vg_replace_malloc.c:711)
==637==    by 0x4E58C16: mysql_init (in /usr/lib64/libmariadb.so.3)
==637==    by 0x7B505E: zbx_db_connect (db.c:494)
==637==    by 0x6EA30C: DBconnect (db.c:73)
==637==    by 0x430DD7: alert_manager_thread (alert_manager.c:1943)
==637==    by 0x66035C: zbx_thread_start (threads.c:133)
==637==    by 0x41E986: MAIN_ZABBIX_ENTRY (server.c:1178)
==637==    by 0x62FBAA: daemon_start (daemon.c:392)
==637==    by 0x41D14D: main (server.c:854)
==637== 
==637== 173,765 (6,360 direct, 167,405 indirect) bytes in 5 blocks are definitely lost in loss record 140 of 140
==637==    at 0x4C30B06: calloc (vg_replace_malloc.c:711)
==637==    by 0x4E58C16: mysql_init (in /usr/lib64/libmariadb.so.3)
==637==    by 0x7B505E: zbx_db_connect (db.c:494)
==637==    by 0x6EA30C: DBconnect (db.c:73)
==637==    by 0x430E9B: alert_manager_thread (alert_manager.c:1963)
==637==    by 0x66035C: zbx_thread_start (threads.c:133)
==637==    by 0x41E986: MAIN_ZABBIX_ENTRY (server.c:1178)
==637==    by 0x62FBAA: daemon_start (daemon.c:392)
==637==    by 0x41D14D: main (server.c:854)
==637== 
==637== LEAK SUMMARY:
==637==    definitely lost: 7,632 bytes in 6 blocks
==637==    indirectly lost: 200,886 bytes in 120 blocks
==637==      possibly lost: 0 bytes in 0 blocks
==637==    still reachable: 146,440 bytes in 244 blocks
==637==         suppressed: 0 bytes in 0 blocks
==637== Reachable blocks (those to which a pointer was found) are not shown.
==637== To see them, rerun with: --leak-check=full --show-leak-kinds=all

==22638== 35,532 (896 direct, 34,636 indirect) bytes in 1 blocks are definitely lost in loss record 103 of 104
==22638==    at 0x4C2EBAB: malloc (vg_replace_malloc.c:299)
==22638==    by 0x4E4767A: ??? (in /usr/lib64/libpq.so.5.10)
==22638==    by 0x4E4DD3A: PQsetdbLogin (in /usr/lib64/libpq.so.5.10)
==22638==    by 0x783163: zbx_db_connect (db.c:542)
==22638==    by 0x6E96AF: DBconnect (db.c:73)
==22638==    by 0x44BAC4: alert_manager_thread (alert_manager.c:1884)
==22638==    by 0x64AAB1: zbx_thread_start (threads.c:128)
==22638==    by 0x43966D: MAIN_ZABBIX_ENTRY (server.c:1130)
==22638==    by 0x61A2F0: daemon_start (daemon.c:392)
==22638==    by 0x437F5D: main (server.c:832)
==22638== 
==22638== LEAK SUMMARY:
==22638==    definitely lost: 896 bytes in 1 blocks
==22638==    indirectly lost: 34,636 bytes in 31 blocks
==22638==      possibly lost: 0 bytes in 0 blocks
==22638==    still reachable: 147,066 bytes in 251 blocks
==22638==         suppressed: 0 bytes in 0 blocks
==22638== Reachable blocks (those to which a pointer was found) are not shown.
==22638== To see them, rerun with: --leak-check=full --show-leak-kinds=all

Index: src/zabbix_server/alerter/alert_manager.c
===================================================================
--- src/zabbix_server/alerter/alert_manager.c	(revision 83601)
+++ src/zabbix_server/alerter/alert_manager.c	(working copy)
@@ -1960,6 +1960,7 @@
 
 		if (ZBX_DB_DOWN == manager.dbstatus && time_connect + ZBX_DB_WAIT_DOWN <= now)
 		{
+			DBclose();
 			if (ZBX_DB_DOWN == (manager.dbstatus = DBconnect(ZBX_DB_CONNECT_ONCE)))
 			{
 				am_queue_watchdog_alerts(&manager);