摘要： 1.分析实例级别的等待。select * from dm_os_wait_stats用来查询各种的情况。下面的查询，分理处重量级的等待(累积总和达到系统总等待时间80%的等待类型，而且至少要返回按等待时间排名前5位的等待)：-- Isolate top waitsWITH Waits AS( SELECT wait_type, wait_time_ms / 1000. AS wait_time_s, 100. * wait_time_ms / SUM(wait_time_ms) OVER() AS pct, ROW_NUMBER() OVER(ORDER BY wait_time_ms DES 阅读全文