1. Got stress? Sometimes the SQL Server needs some too
Peter Shore
SQL Saturday Cleveland 2017

2. Agenda Introduction Testing Why we want stress Distributed Replay
OStress
SQL Query Stress
HammerDB

3. Who am I? Platform Database Consultant – BlueChip Consulting Group
Intentionally Accidental DBA
Over 20 years IT experience
Server Engineer
Desktop Engineer
Network Infrastructure
Desk side support
President CBusPASS
Co-Organizer SQL Saturday Columbus
Member Multiple Virtual Chapters
How to find me

4. Stress
The confusion caused when ones mind overrides the body’s natural desire to choke the living **** out of some ***hole that desperately needs it.
The non-specific response of the body to any demand for change
Fulfillment of an infinite number of requests via finite set of resources

5. Why stress SQL Server? To remove stress from SQL Server Test queries
“Break in” new servers
Benchmark

6. Causes of SQL Stress Query Database Instance Noisy Neighbors
Poorly written query/queries
Death by 1,000 cuts
Database
Many users/queries interacting with the database
Instance
Other databases that are highly active
Noisy Neighbors
Other SQL instances on the server
Other applications on the server
Other servers on the virtualization host

7. Stress Testing SQL Server
Write our own test
Mission specific
High degree of control
Time consuming
Single Query tools
Ostress
SQL Query Stress
Database tools
HammerDB
Instance Tools
Distributed Replay

8. Distributed Replay Microsoft supplied and supported
Debuted SQL Server 2012
Uses Profiler Trace to capture a workload
Must capture from SQL 2005 or later
Similar to replaying trace
Playback against a different server
Can be played through multiple clients simultaneously
Any number from 1 through 16

9. Distributed Replay

10. Distributed Replay Use Cases Installation & Configuration
Test SQL Version upgrade
Test Windows/SQL service packs/cumulative updates/patches
Test hardware upgrades
Test virtualization
Provide load for performance testing
If multiple reply clients are needed
Installation & Configuration
Installs from SQL Server installation media
Use local or domain service accounts
Firewall exceptions may be needed

11. Distributed Replay Usage
Create new trace using the TSQL – Replay template
Capture workload & save trace
Preprocess the trace files to prepare for distributed clients
Replay against target server using 1 or more clients

12. Distributed Replay Reference Links Overview Installation Usage Forum
Installation
load-test-your-sql-serverpart-1/
distributed-replay/
Usage
load-test-your-sql-serverpart-2/
multiple-clients-using-sql-server-2012-distributed-replay/
Forum

13. OSTRESS Part of RML Utilities Command prompt based Multi-threaded
Can be used as part of a script
Multi-threaded
ODBC based
Simulates multiple connections
Is able to replay trace files or run scripts

14. OSTRESS In-line query Query from file All the script files in a folder
ostress -E -d"StackOverflow" -Q"select U.Reputation, C.Text from dbo.Users as U inner join dbo.Comments as C on U.Id = C.Id" -n"10" - o"C:\temp“
Query from file
Ostress.exe –ic:\AmitStresTest\stress_01.sql –n200 –r2000 –oc:\ AmitStresTest \output (sample from SQLServergeeks.com)
All the script files in a folder
Ostress.exe –ic:\temp\*.sql – n100 – r1000 –oc:\temp\output (sample from SQLConsulting.com)

15. OSTRESS OStress Replay Control Agent (ORCA)
Conceptually similar to Distributed Replay
Requires same hardware architecture and version of RML Utilities
Use the OStress control.ini to point to ORCA server

16. OSTRESS Background and link to installer ORCA and OStress
replay-markup-language-rml-utilities-for-sql-server
ORCA and OStress
machine-replay-using-orca-and-ostress/

17. SQL Query Stress Originally written by Adam Machanic
Maintained by Erik Ejlskov Jensen
Single exe
GUI based tool to run one query multiple times
Able to run multiple times on the same machine

18. SQL Query Stress Reference links GitHub
Too many references to link on Adam Machanic’s site

19. HammerDB Open source Load test/benchmarking tool
Not just for SQL Server
GUI based graphical database
Limits command line functionality
Customizable workloads, if you know TCL

20. HammerDB Usage Change BENCHMARK to MS SQL Server Schema Build
Set name of server
Can change name of database, but the target must be empty
Adjust number of warehouses & users to build warehouses
Double click build
Driver Script
Set database connection
Set number of transactions per user or the length of the test in time
Double click load
Click green arrow to run test

21. HammerDB Reference http://www.hammerdb.com/index.html
All documentation can be found on the site

22. Questions?