About Me: Brent Ozar. Perfmon and Profiler 101

Transcription

1 Perfmon and Profiler Quest Software, Inc. ALL RIGHTS RESERVED. About Me: Brent Ozar SQL Server Expert for Quest Software Former SQL DBA Managed >80tb SAN, VMware Dot-com-crash experience Specializes in performance tuning 1

2 Today s Agenda The Honda Civic and the Nissan GT-R Metrics, Trace, Mitigations A New Secret Weapon Resources and Q&A If You Don t Need to Go Fast From 2

3 But The Faster You Want To Go The More You Have To Measure 3

4 Windows Check Engine Light And If You Wanna Go Fast: 4

5 Two Approaches to Detection Exceptions Monitoring: Check Engine Proactive Monitoring: Detailed Gauges Where Do We Start? Hardware Windows SQL Server Tables, Indexes Query 5

6 Capture Metrics With Perfmon Performance Monitor, aka Perfmon Ships with all Windows versions Polls any server from your desktop Pulls performance metrics Writes them to a file Requires some OS permissions Does not include alerts or analytics 11 6

7 Memory Counters Memory Available Mbytes Paging File - % Usage SQLServer:Buffer Manager Buffer cache hit ratio Page life expectancy SQLServer:Memory Manager Memory Grants Pending 7

8 Storage Metrics: Physical Disk % Disk Time Avg. Disk Queue Length Avg. Disk sec/read Avg. Disk sec/write Disk Reads/sec Disk Writes/sec CPU Metrics Processor - % Processor Time System Processor Queue Length SQLServer:General Statistics User Connections (not CPU, just other ) 8

9 The Raw Output: CSV Files 16 Adding Analytical Formulas 17 9

10 That s a Lot of Zeroes! 18 Sorting High to Low 19 10

11 What To Look For, In Order System Processor Queue Length Memory Available Mbytes Lock pages in memory! What To Look For Next Disk metrics on the page file drive Disk metrics on the log file drive Disk metrics on the data file drive Disk metrics on the TempDB drive 11

12 Got Everything on One Drive? Narrow it down with the DMV sys.dm_io_virtual_file_stats _ What If We Could Data Mine It? 12

13 Table Analysis Tools For The Cloud Detecting Categories of Load 13

14 Capture Queries with a Trace Columns to Capture What s Going On What The Impact Was Text Data CPU DatabaseID and/or Reads DatabaseName Writes Login Name Duration Host Name Start Time Application Name End Time 14

15 Profiler s Results: A Trace Table Order By Duration Descending 15

16 Casting and Grouping Another Cloud Analytics Candidate 16

17 Another Way: Perf Dashboard Correlate Metrics & Trace Show a cause and effect relationship Fields to mentally join on: Date/Time ranges CPU Reads/Writes Duration 17

18 Sample Problem #1 Metrics tell us: Very high disk queue lengths on data drive Trace tells us: Report queries doing table scans w/o indexes Many scheduled reports run simultaneously l Ways We Can Mitigate It Add covering indexes Modify existing indexes Run reports serially, not all at once Add hard drives to the data file array Add memory to cache scanned tables 18

19 Sample Problem #2 Metrics tell us: Page file drive queue lengths average >20 Page file use averages >1% Available memory averages <200mb Buffer cache hit ratio and page life expectancy are high Trace tells us: No unusual queries Memory Configuration Server: 4gb ram OS: 1gb SQL: 3gb App: 1gb 19

20 Ways We Can Mitigate It Add memory and enable AWE/PAE Add memory and upgrade to 64-bit Reduce SQL s min/max memory sizes Move the app to its own server Sample Problem #3 Metric looks OK, but every 15 minutes: Long drive queues on the log file drive Page life expectancy drops near zero Network traffic jumps Trace tells us: Transaction log backups are running 20

21 Ways We Can Mitigate It Stop doing log backups Put the databases in simple mode Add drives to the transaction log array Throttle the transaction log backups Sample Problem #4 Metrics tell us: CPU average is high Disk, memory look OK Trace tells us: Queries are using cursors Operating on individual records, not sets 21

22 How We Can Mitigate It Change cursor to set-based query Buy really fast processors Spend a lot on licensing Wrapping Things Up Double-check the event log first Don t get overwhelmed: focus with the Metric Trace Mitigation process Show a clear cause and effect Use cloud-based BI to get an edge 22

23 Resources On The Web My posts about Perfmon and analytics: Excel Table Analysis Tools for the Cloud: SQL Server community: SQLServerPedia.com 23