InstantForum.NET v2.9.0SQLServerCentralhttp://www.sqlservercentral.com/Forums/notifications@sqlservercentral.comSat, 25 May 2013 00:29:41 GMT20http://www.sqlservercentral.com/Forums/Topic1357147-1550-1.aspx[quote][b]t.brown 89142 (9/11/2012)[/b][hr]Just noticed your name in the sig line - and that you're technical reviewer on the book![/quote]Yup[quote] and apologies - yours isn't a picture of Obi-Wan either is it?[/quote]It's Qui-gon Jinn from Phantom Menace.Tue, 11 Sep 2012 04:22:36 GMTGilaMonsterhttp://www.sqlservercentral.com/Forums/Topic1357147-1550-1.aspxHi Gail, Just noticed your name in the sig line - and that you're technical reviewer on the book! and apologies - yours isn't a picture of Obi-Wan either is it?Tue, 11 Sep 2012 04:19:36 GMTt.brown 89142http://www.sqlservercentral.com/Forums/Topic1357147-1550-1.aspxWe'd have easily written 1200 pages, but the deadline was against us. :-)Tue, 11 Sep 2012 03:59:09 GMTGilaMonsterhttp://www.sqlservercentral.com/Forums/Topic1357147-1550-1.aspxThanks for the free book, Obi-Wan.Looks pretty comprehensive from a first skim through, and small enough to read it all (*not* a 1200 page monster - which is good)Tue, 11 Sep 2012 03:10:17 GMTt.brown 89142http://www.sqlservercentral.com/Forums/Topic1357147-1550-1.aspx[url]http://www.simple-talk.com/books/sql-books/troubleshooting-sql-server-a-guide-for-the-accidental-dba/[/url]Start with chapter 1.Tue, 11 Sep 2012 02:52:09 GMTGilaMonsterhttp://www.sqlservercentral.com/Forums/Topic1357147-1550-1.aspxI think you mean its 35% of the wait time after excluding all those other waits.it *may* be negligible in proportion to all waits.Before looking at hardware you should really investigate the querys that are causing the waits - you can also look at the missing index stats, which may provide some clues.If users are experiencing performance problems, what are they? is it only certain queries?, only on one database?, or just generally slow?Tue, 11 Sep 2012 02:49:49 GMTt.brown 89142http://www.sqlservercentral.com/Forums/Topic1357147-1550-1.aspxHi AllI'm using the following script to assess my highest wait_types ona fairly new SQL Server (+- 2 weeks)[code="sql"]SELECT TOP 15wait_type ,wait_time_ms ,signal_wait_time_ms ,wait_time_ms - signal_wait_time_ms AS resource_wait_time_ms ,100.0 * wait_time_ms / SUM(wait_time_ms) OVER ( )AS percent_total_waits ,100.0 * signal_wait_time_ms / SUM(signal_wait_time_ms) OVER ( )AS percent_total_signal_waits ,100.0 * ( wait_time_ms - signal_wait_time_ms )/ SUM(wait_time_ms) OVER ( ) AS percent_total_resource_waitsFROM sys.dm_os_wait_statsWHERE wait_time_ms > 0 -- remove zero wait_timeAND wait_type NOT IN -- filter out additional irrelevant waits( 'SLEEP_TASK', 'BROKER_TASK_STOP', 'BROKER_TO_FLUSH','SQLTRACE_BUFFER_FLUSH','CLR_AUTO_EVENT', 'CLR_MANUAL_EVENT','LAZYWRITER_SLEEP', 'SLEEP_SYSTEMTASK', 'SLEEP_BPOOL_FLUSH','BROKER_EVENTHANDLER', 'XE_DISPATCHER_WAIT', 'FT_IFTSHC_MUTEX','CHECKPOINT_QUEUE', 'FT_IFTS_SCHEDULER_IDLE_WAIT','BROKER_TRANSMITTER', 'FT_IFTSHC_MUTEX', 'KSOURCE_WAKEUP','LAZYWRITER_SLEEP', 'LOGMGR_QUEUE', 'ONDEMAND_TASK_QUEUE','REQUEST_FOR_DEADLOCK_SEARCH', 'XE_TIMER_EVENT', 'BAD_PAGE_PROCESS','DBMIRROR_EVENTS_QUEUE', 'BROKER_RECEIVE_WAITFOR','PREEMPTIVE_OS_GETPROCADDRESS', 'PREEMPTIVE_OS_AUTHENTICATIONOPS','WAITFOR', 'DISPATCHER_QUEUE_SEMAPHORE', 'XE_DISPATCHER_JOIN','RESOURCE_QUEUE' )ORDER BY wait_time_ms DESC[/code]The highest wait type is for PAGEIOLATCH_SH and it shows that this wait_type contributes 35% of the total waits.Where can I start troubleshooting this wait? Is this a sign of a slow disk subsystem or should I start looking at my CPU pressure or is it query related?Any help would be greatThanksMon, 10 Sep 2012 23:56:37 GMTSQLSACT