SqlServer重建所以表索引后变慢的问题

数据库一直慢，前两天执行了这个语句重建了所有索引， EXEC sp_MSForEachTable 'ALTER INDEX ALL ON ? REBUILD WITH ( PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, SORT_IN_TEMPDB = OFF, OnLINE= OFF)'

数据库一直慢，前两天执行了这个语句重建了所有索引，

EXEC sp_MSForEachTable 'ALTER INDEX ALL ON ? REBUILD WITH (
PAD_INDEX = OFF,
STATISTICS_NORECOMPUTE = OFF,
ALLOW_ROW_LOCKS = ON,
ALLOW_PAGE_LOCKS = ON,
SORT_IN_TEMPDB = OFF,
OnLINE= OFF)'

，然后有收缩了数据库，整个系统突然变得奇慢无比，就是打开页面后，一直是空白状态加载不出来，系统用户较多，服务器操作系统是 window server2008 ，不知道和IIS有没有关系，还是重建索引和收缩数据库操作的问题，怎么回事，盼大牛答复