EOH: A Microsoft Partner INTRODUCTION TO EXTENDED EVENTS

What is XE  Extended Events: – Replacement for SQL Profiler (Deprecated) – XE features on all editions  Event handling framework for systems  Used for diagnostics, tracing and auditing  XE combines information from SQL Server and OS

XE Architecture – Courtesy BOL

 Packages Parent container contained attributes of events within the package Three Types – Package0 – SQLServer – SQLOS – 1 Internal XE Components

 Events Two Categories – 4 Channels (Grouping of Events) – Keyword (Specific) Defined point in task XE Components

 Targets Consume events & output event data Six target types – File – Histogram – Counter – Pairing – ETW – Ring Buffer XE Components

 Actions Response\s to an event. All actions are SYNC. Collects object details from EVENT. – TSQL capture\ Plan handle\ Numa ID etc. Certain events can have unique actions. XE Components

 Predicates Boolean expressions that have a failure on first false evaluation. Applied per event not per session. Order of predicates can affect performance. Rich evaluation and filtering contexts XE Components

GLOBAL EVENT SESSION DATA  sys.server_event_sessions  sys.server_event_session_target  sys.server_event_session_fields  sys.server_event_session_actions  sys.server_event_session_events Metadata – System Views

EVENT SYSTEM DATA  sys.dm_xe_packages  sys.dm_xe_objects  sys.dm_xe_object_columns  sys.dm_xe_map_values Metadata - DMVs

ACTIVE SESSION DATA  sys.dm_xe_sessions  sys.dm_xe_session_targets  sys.dm_xe_events  sys.dm_xe_event_actions Meta Data - DMVs

Querying XE system Tables And DMVs DEMO

 CREATE EVENT SESSION…ON SERVER  ALTER EVENT SESSION…ON SERVER  DROP EVENT SESSION…ON SERVER  COMMON OPTIONS: – MAX_DISPATCH_LATENCY – MAX_MEMORY – STARTUP_STATE – EVENT_RETENTION_MODE SINGLE MULTIPLE NONE XE DDL

XE DDL DEMO

 Real-time amendment of events and predicates.  SSMS GUI interface.  Different stores for output.  Event correlation available.  Profiler Deprecated (Repeat )  Less Overhead. SQL Trace vs XE

 sys.trace_xe_event_map  sys.trace_xe_action_map  sp_BlitzTrace Migrating Profiler to XE

 Deadlocks  Page splits – fill factor  Auditing – Internal Use only  CPU and IO tracking  Wait stats  Queries by duration  General troubleshooting Use Case Scenarios

USE CASES DEMO

 Additional XE objects added.  Live data view.  GUI interface. Aggregation and filtering in UI New session wizard Create new session Templates View Target Data Customizing View Live Data watch Enhancements in SQL 2012\4

SSMS XE GUI DEMO

 Pair Matching considerations.  Partitioning nodes.  Predicates.  Use the MAX option to control overhead.  Use sampling to minimize result sets. Best Practices & Considerations

 Idera XE Profiler  sp_BlitzTrace – Brent Ozar  Jonathan Kehayias – SQLSkills XE SSMS 2008 Add-In (codeplex) Deep Dive Blogs (msdn & sqlskills.com)  Mike Wachel – MSFT XE Engine developer  XTrace (WinSDK) Tools for OS\SQL\APP debug Useful Resources

 Donovan White   Questions & Answers