更改服务器后，我们现在只需一个查询就会遇到极慢的执行时间。当我们在运行时分析会话时，我们会看到数百个（有时超过1000个）打开的会话都具有相同的会话ID，并且它们会自行阻止。这是一个摘录：
+----------------------+------------+-----------------+------------------+-----------+--------------------+-----------------------+---------------------+--------------------------+--------------------------------------------------------------------+
| waiting_task_address | session_id | exec_context_id | wait_duration_ms | wait_type | resource_address | blocking_task_address | blocking_session_id | blocking_exec_context_id | resource_description |
+----------------------+------------+-----------------+------------------+-----------+--------------------+-----------------------+---------------------+--------------------------+--------------------------------------------------------------------+
| 0x00000005A3B83468 | 161 | 19 | 121058 | CXPACKET | 0x0000000EB9B9C830 | 0x00000010BF029C28 | 161 | 3 | exchangeEvent id=Pipe8a2d88200 WaitType=e_waitPipeNewRow nodeId=12 |
| 0x00000010BE003C28 | 161 | 10 | 121079 | CXPACKET | 0x00000008A1A0E9C0 | 0x00000005734964E8 | 161 | 93 | exchangeEvent id=Pipe79fcc6200 WaitType=e_waitPipeNewRow nodeId=8 |
| 0x000000050BFA1088 | 161 | 42 | 121092 | CXPACKET | 0x000000058C7C12D0 | 0x00000010B484A8C8 | 161 | 27 | exchangeEvent id=Pipe5647e2110 WaitType=e_waitPipeNewRow nodeId=15 |
| 0x0000000DFB199088 | 161 | 20 | 121094 | CXPACKET | 0x0000000E77A4DCC0 | 0x00000005A3B82CA8 | 161 | 44 | exchangeEvent id=Pipe915578ed0 WaitType=e_waitPipeGetRow nodeId=15 |
| 0x0000000E501A64E8 | 161 | 66 | 121094 | CXPACKET | 0x000000088DB9DCB0 | 0x0000000E44591C28 | 161 | 81 | exchangeEvent id=Pipe79fcc8d00 WaitType=e_waitPipeGetRow nodeId=5 |
| 0x0000000E501A64E8 | 161 | 66 | 121094 | CXPACKET | 0x000000088DB9DCB0 | 0x00000003714868C8 | 161 | 82 | exchangeEvent id=Pipe79fcc8d00 WaitType=e_waitPipeGetRow nodeId=5 |
| 0x0000000E501A64E8 | 161 | 66 | 121094 | CXPACKET | 0x000000088DB9DCB0 | 0x0000000DC854B848 | 161 | 83 | exchangeEvent id=Pipe79fcc8d00 WaitType=e_waitPipeGetRow nodeId=5 |
| 0x0000000E501A64E8 | 161 | 66 | 121094 | CXPACKET | 0x000000088DB9DCB0 | 0x00000010B3A25848 | 161 | 84 | exchangeEvent id=Pipe79fcc8d00 WaitType=e_waitPipeGetRow nodeId=5 |
| 0x0000000E501A64E8 | 161 | 66 | 121094 | CXPACKET | 0x000000088DB9DCB0 | 0x0000000F39DFA4E8 | 161 | 85 | exchangeEvent id=Pipe79fcc8d00 WaitType=e_waitPipeGetRow nodeId=5 |
+----------------------+------------+-----------------+------------------+-----------+--------------------+-----------------------+---------------------+--------------------------+--------------------------------------------------------------------+
我不确定是什么原因引起的。移动服务器之前，问题不存在。我们有一段很短的时间，在此期间查询在当前服务器上快速执行，现在再次出现执行时间慢的问题。
答案 0 :(得分：0)
您是否比较了执行计划？如果您已将SQL升级到较新版本，您是否更新了统计信息？如果这些是不同的服务器与相同的数据库是相同的数据？索引是否相同？我曾经运行复制拓扑，并会删除订阅者上未使用的索引。
自我封锁并非真正阻挡。我认为他们在SQL 2005中引入了它并且它只是缓慢。