1. Using Extended Events to Diagnose Application Issues
Mind the Gap
Using Extended Events to
Diagnose Application Issues
Mindy Curnutt
Partner
Mindy Curnutt & Associates Consulting

2. About Me Wife & Mother Busy-Bee Musician Soap Making Baking Crocheting
Entrepreneur
Event Planning

3. About Me Independent Consultant 4X MS Data Platform MVP Idera ACE 2017
SQL Server since 6.5 / 1995 (20+ Years)
SQLPASS Speaker, 2005, , 2017
PASS Program Manager

4. AGENDA
Overview Profiler or Extended Events? Long Running Queries A Thousand Paper Cuts The Sounds of Silence Summary

5. OVERVIEW When to use How to Use Long Running Queries
Profiler or Extended Events
When to use
How to Use
3 Methods
Long Running Queries
A Thousand Paper Cuts
The Sounds of Silence

6. AGENDA
Overview Profiler or Extended Events? Long Running Queries A Thousand Paper Cuts The Sounds of Silence Summary

7. PROFILER TRACE
Less Than 200 Events Heavier than XEvents No New Events after SQL 2008 Deprecated by Microsoft Easier to Use prior to SQL 2012

8. PROFILER VS EXTENDED EVENTS
Like Profiler's Older Brother (or Sister!) - Bigger, More Mature, More Versatile Lighter Weight Easy to use with SQL 2012+

9. PROFILER VS EXTENDED EVENTS
Version
Events
GUI
Adoption
20008
254 No
Low
2008R2
263
2012
596
Yes
Low-Medium
2014
815
Medium
2016
1303

10. EVENTS TO TRACK Profiler Extended Events 10 - RPC:Completed
sqlserver.rpc_completed
12 - SQL:BatchCompleted
sqlserver.sql_batch_completed
45 - SP:StmtCompleted
sqlserver.sp_statement_completed

11. SP_Statement_Completed
Default=Black / Additional=Red
Extended Events
Profiler Columns
SP_Statement_Completed
SQL_Batch_Completed
RPC_Completed
1 textdata
statement
batch_text
3 databaseid
source_database_id
database_id
4 transactionid
transaction_id
5 linenumber
line_number
6 ntusername
nt_username
8 hostname
client_hostname
10 applicationname
client_app_name
11 loginname
server_principal_name
12 spid
session_id
13 duration
duration
14 starttime
15 endtime
timestamp
16 reads
logical_reads
physical_reads
17 writes
writes
18 cpu
cpu_time
22 objectid
object_id
26 servername
server_instance_name
27 eventclass
name
34 objectname
object_name
35 databasename
database_name
48 rowcounts
row_count

12. AGENDA
Overview Profiler or Extended Events? Long Running Queries A Thousand Paper Cuts The Sounds of Silence Summary

13. LONG RUNNING QUERIES Resource Consumers Blockers Easy to Spot
Low Hanging Fruit?

14. LONG RUNNING QUERIES When Useful? Occasional Slowness Blocking Issues
Specific Application Area Slowness
No Budget for 3rd Party Tools
After the Fact Analysis
Need Drill Down (Stmt within Proc)

15. LONG RUNNING QUERIES Events to Capture RPC: Completed
SQL Batch: Completed
SP: Statement Completed
Filter
Duration > X (example: 5 seconds*)
Length of Trace
Long (Can run daily, all day)
Performance Hit
Low

16. LONG RUNNING QUERIES
Profiler Demo
Capture
Review
XEvents Demo

17. AGENDA
Overview Profiler or Extended Events? Long Running Queries A Thousand Paper Cuts The Sounds of Silence Summary

18. A THOUSAND PAPER CUTS Like Being Buried Alive by Pebbles! Problem:
Many, Many
Individually Quick
Statements
RBAR – “Row by Agonizing Row”

19. A THOUSAND PAPER CUTS Resource Consumers Takes Analysis to Spot
Diagnosis may require causing temporary Performance Degradation
Typical Causes:
A Data Access Layer writing SQL code
Non Set-Based SQL
Scalar Functions
Trigger that fire other Triggers

20. A THOUSAND PAPER CUTS When Useful? Specific Application Area Slowness
Working Directly with User or QA
No Budget for 3rd Party Tools
Long Running Query Approach Comes Up Dry

21. A THOUSAND PAPER CUTS Events to Capture RPC: Completed
SQL Batch: Completed
Filter
Duration Filter = 0 (be careful!)
User Specific Item (spid, login name…)
Length of Trace
Very Short
Performance Hit
High

22. A THOUSAND PAPER CUTS
Profiler Demo
Capture
Review
XEvents Demo

23. AGENDA
Overview Profiler or Extended Events? Long Running Queries A Thousand Paper Cuts The Sounds of Silence Summary

24. The sounds of silence SQL not responsible for the
Slowness being experienced.
Problem:
User experience is poor
SQL utilization low
LRQ Traces show nothing
TPCs are minimal
Is something causing delay between SQL calls?
Waitstats will not show this

25. The sounds of silence Takes Analysis & Intuition to Spot
Diagnosis may require causing temporary Performance Degradation
Typical Causes:
WAN
Firmware
Overloaded Application Host
Application making a synchronous call to something else

26. The sounds of silence Specific Application Area Slowness
When Useful?
Specific Application Area Slowness
Working Directly with User or QA
No Budget for 3rd Party Tools
Long Running Query Approach Comes Up Dry
Thousand Paper Cut Analysis Comes Up Dry
Waitstats look fine

27. The sounds of silence Scenario 1: Latency Duration % of Time
User Experience
308ms
100%
SQL Queries
14ms 5%
SQL Waiting
294ms
95%

28. The sounds of silence Scenario 2: Pauses within the Application
Duration
% of Time
User Experience
310ms
100%
SQL Queries
13ms 5%
SQL Waiting
297ms
95%

29. The sounds of silence Events to Capture RPC: Completed
SQL Batch: Completed
Filter
Duration Filter = 0 (be careful!)
User Specific Item (spid, login name…)
Length of Trace
Very Short
Performance Hit
High

30. The sounds of silence
Profiler Demo
Review
XEvents Demo

31. AGENDA
Overview Profiler or Extended Events? Long Running Queries A Thousand Paper Cuts The Sounds of Silence Summary

32. sUMMARY
LRQ = Long Running Query TPC = Thousand Paper Cuts SOS = Sounds of Silence
LRQ
TPC
SOS
Diagnosis
Easy
Hard
Occasional Slowness?
Yes No
Specific Slowness?
Maybe
Capture Baseline or History
Filter On
Duration
User
Length of Trace
Long
Short
Performance Hit
Low
High

33. QUESTIONS? Mindy Curnutt Independent Consultantw: e:
M O V I N G Y O U F O R W A R D