I am trying to monitor live performance data and usage, which cannot be tracked with PerformanceMonitor. What are the consequences of reading DMVs in a production live OLTP database? : Eg: sys.dm_tran_locks, sys.dm_os_waiting_tasks, sys.dm_os_performance_counters, sys.dm_exec_connections, sys.dm_io_virtual_file_stats, sys.dm_exec_sql_text,etc
Should I just utilize WITH (NOLOCK) when querying Dmvs? Would this resolve many of the resource issues? Is there anything such as dirty read rollbacks in DMVs. I know it can exist in applications tables eg where someone submits an order then cancels, etc. Additionally, with NOLOCK, is there higher chance query will continue forever in high volume environment since I am not locking rows, pages, and things will continue be added into DMV TableView?
Thank you,