How to troubleshoot SQL Server performance issues. To troubleshoot performance issues, you must complete a series of steps to isolate and determine the cause of the problem. Possible causes include: BlockingSystem resource contentionApplication design problemsQueries or stored procedures that have long execution times Identifying these causes is typically very time consuming, and you may spend several days evaluating the collected information. The complexity of the performance analysis is not specific to a particular database product or operating system. All applications are subject to performance constraints because of resource, design, or usage factors.
For more information, click the following article number to view the article in the Microsoft Knowledge Base: ( ) How to troubleshoot application performance with SQL Server After the problem occurs, collect the following information and have it available: Blocker script output The blocker script is critical for identifying blocking scenarios. A Performance Troubleshooting Methodology for SQL Server.
When healing a sick SQL Server, you must forget the idea that there could ever be a simple correspondence between symptom and disease: The art of troubleshooting is much more the art of discovering, and assembling, the various pieces of the puzzle so that you have a complete understanding of what is going on inside of a server Knowing where to start is the toughest part of solving a problem. As a Senior Database Administrator, I prided myself on being able to pinpoint the root cause of problems in my servers, and quickly restore services to normal working order.
The ability to do this is partly down to a sound knowledge of your SQL Server environment, partly to having the right tools and scripts, and partly to what you learn to look out for, based on hard-earned lessons of the past. I see, yet I cannot see the wood for the trees. If you collect and examine individually five separate pieces of performance data, it's possible that each could send you down a separate path.
Jonathan Kehayias - The Rambling DBA. Last week someone sent Kimberly an email asking what the read_microsec column in the sys.dm_os_buffer_descriptors DMV in SQL Server 2012 showed. The email was passed around our team and to be honest it was the first time I’d even heard of the column existing. The questioner also wanted to know if/how the read_microsec column be used. The Books Online topic for sys.dm_os_buffer_descriptors defines this column as, “The actual time (in microseconds) required to read the page into the buffer.
This number is reset when the buffer is reused.” This would make you think that the counter is per-page in the buffer pool, but I wanted to see what exactly it correlates to, and the results aren’t quite as straightforward as the Books Online description might seem. Investigating this further To look at this further, the first thing to do is identify the Page ID for a specific row in a database that we can use for tracking the I/O associated with bringing that page into the buffer pool. Summary. Simplify Process Troubleshooting with DebugDiag. When troubleshooting application-stability concerns and performance problems such as crashes, hangs, and high memory usage, sometimes you need to examine the process that was active when the problem occurred. To complicate troubleshooting, server applications such as Microsoft IIS, Exchange Server, SQL Server, COM+, and BizTalk Server often display no UI and restart automatically without indicating what caused them to fail.
Having the right debugging tool to isolate a problem can make finding the solution much easier. For such problems, Debug Diagnostic Tool (DebugDiag) is often a better choice than other debugging tools such as ADPlus, Userdump, and WinDbg. I’ll explain why and will walk you through using Debug- Diag to troubleshoot a process crash. Why Use DebugDiag? A commonly used workaround is to restart the process or service in hopes that whatever caused the crash will no longer occur. Now you’ll see the main DebugDiag application window, which has three tabs. Performance Troubleshooting using the PAL tool - Mike Lagase. If you have had Exchange performance issues in the past, you must know by now that there are a lot of variables that affect Exchange overall performance and sometimes took a long time to find root cause of those problems as they can get quite complex.
If you are looking for some more detailed reports with some added charting capabilities, there is the Performance Analyzer Tool or PAL that you can grab from . PAL is an extremely useful and powerful tool for automatically generating HTML reports that were collected from a performance monitor counter log. This tool uses a subset of dependencies such as Log Parser and the Office Web Components to create these reports. PAL uses XML configuration files that parse the most important counters for Exchange performance issues and throws alerts when thresholds are exceeded for those counters.
All that is needed is a blg file that was previously collected. Let’s take a look at what kind of reports this creates. 1. 2. Mike. Httping. Capturar volcados con DebugDiag usando contadores de rendimiento - Desarrollo Web. Vamos a utilizar el Debug Diagnostic Tool (DebugDiag) para configurar reglas que se activen cuando se cumplan unos requisitos relacionados con los contadores de rendimiento. En concreto voy a poner de ejemplo cómo configurarlos para un consumo alto de CPU. Lo que vamos a hacer es crear una regla que se active cuando el consumo del procesador sea superior al 80% durante 5 segundos y capture 3 volcados de memoria cada 30 segundos.
Ahora viene la pregunta ¿por qué tenemos que capturar 3 volcados y por qué cada 30 segundos?. La respuesta es sencilla, un solo volcado puede darnos una información sesgada porque sólo veríamos unos hilos en ejecución pero no sabríamos cuánto tiempo habrían estado ejecutándose, si están parados, o si hemos cogido por casualidad al Garbage Collector funcionando… Los 30 segundos entre volcados nos indican cómo es la evolución de la aplicación en el tiempo.
No olvidemos que 30 segundos en una ejecución de internet es un periodo que se puede considerar lago. Capturar volcados con DebugDiag usando contadores de rendimiento - Desarrollo Web. Performance Analysis of Logs (PAL) Tool - Home. Get a Handle on Windows Performance Analysis. As an administrator, you probably know firsthand that manually analyzing Performance Monitor logs is a time-consuming process, requiring both a deep-level knowledge of performance counters and familiarity with Windows architecture. The Microsoft Global Escalation Services team gets thousands of calls from customers requesting help in analyzing Performance Monitor logs either to help solve an existing problem or determine whether their servers are optimized for the best possible performance. I’ll tell you about some tools that Microsoft support uses for system performance analysis, which can help you more easily and effectively analyze your systems’ performance and troubleshoot performance issues.
Two-Part AnalysisPerformance analysis comprises two main tasks: Data collection: Collecting Performance Monitor logs locally or remotely can be challenging as the number of systems to be monitored increases. Let’s look at tools you can use to handle each performance-analysis task. Performance Analysis of Logs (PAL) Tool - Home. How to troubleshoot SQL Server performance issues. Top 10 SQL Server Counters for Monitoring SQL Server Performance. Do you have a list of SQL Server Counters you review when monitoring your SQL Server environment? Counters allow you a method to measure current performance, as well as performance over time. Identifying the metrics you like to use to measure SQL Server performance and collecting them over time gives you a quick and easy way to identify SQL Server problems, as well as graph your performance trend over time.
Below is my top 10 list of SQL Server counters in no particular order. For each counter I have described what it is, and in some cases I have described the ideal value of these counters. This list should give you a starting point for developing the metrics you want to use to measure database performance in your SQL Server environment. 1. The buffer cache hit ratio counter represents how often SQL Server is able to find data pages in its buffer cache when a query needs a data page. 2. The page life expectancy counter measures how long pages stay in the buffer cache in seconds. 3. 4.