The server updates hosts availability in incorrect order. It can cause deadlock.

3576:20131012:201602.109 In process_host_availability()
3576:20131012:201602.110 query [txnlev:1] [begin;]
3576:20131012:201602.110 query [txnlev:1] [update hosts set available=2,snmp_available=0,ipmi_available=0,jmx_available=0,error='Get value from agent failed: cannot connect to [[127.0.0.1]:10050]: [111] Connection refused',snmp_error='',ipmi_error='',jmx_error='' where hostid=10084;
update hosts set available=2,snmp_available=0,ipmi_available=0,jmx_available=0,error='Get value from agent failed: cannot connect to [[127.0.0.1]:10050]: [111] Connection refused',snmp_error='',ipmi_error='',jmx_error='' where hostid=10089;
update hosts set available=2,snmp_available=0,ipmi_available=0,jmx_available=0,error='Get value from agent failed: cannot connect to [[127.0.0.1]:10050]: [111] Connection refused',snmp_error='',ipmi_error='',jmx_error='' where hostid=10086;
update hosts set available=2,snmp_available=0,ipmi_available=0,jmx_available=0,error='Get value from agent failed: cannot connect to [[127.0.0.1]:10050]: [111] Connection refused',snmp_error='',ipmi_error='',jmx_error='' where hostid=10088;
update hosts set available=2,snmp_available=0,ipmi_available=0,jmx_available=0,error='Get value from agent failed: cannot connect to [[127.0.0.1]:10050]: [111] Connection refused',snmp_error='',ipmi_error='',jmx_error='' where hostid=10087;
]
3576:20131012:201602.112 query [txnlev:1] [commit;]
3576:20131012:201602.112 End of process_host_availability()