2 Replies Latest reply on Nov 21, 2011 11:37 AM by Milton.Harris

    how to check SAN perfomance

    bibinbabu

      [View:/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.11.31.97/DS4700-IBM.docx]Could you please assist me regarding how to check the Storage performance.  We are using IBM DS4700 for SQL Database. LUN ID “Database” for SQL database and LUN ID “Logs” for SQL Logs. Our application Team complaining that SQL performance very slow  and I need to check the SAN LUN performance. When I open  SolarWinds Storage there is many option in the “Chart:” which option I need to select mainly and what is the definition of each components? Is there any recommenced IO performance? Kindly advice


      Regards


      Bibin

        • Re: how to check SAN perfomance
          mdharris420

          I would use a utility like this one to determine if your I/O subsystem is the source of the bottleneck.

          http://sourceforge.net/projects/iometer/

           

          Or alternatively you can read this thread:

          http://www.mysqlperformanceblog.com/2008/03/05/evaluating-io-subsystem-performance-for-mysql-needs/

          • Re: how to check SAN perfomance
            Milton.Harris

            When was the last time you ran the MYSQL database maintenance job against that database? You might need to run a MYISAMDBCHK in order to rebuild table indexes to streamline performance, otherwise as is your database might be working to hard to scan the entire contents of the tables in order to retrieve simple select sql query data and throw it on the page.

            In order to get a better idea of how your MYSQL db is performing you will want to get at the minimum the following (5) metrics: 

            1) Total Memory Used:

            SELECT (

                 SUM(VARIABLE_VALUE) *

                 (SELECT VARIABLE_VALUE FROM SESSION_VARIABLES WHERE VARIABLE_NAME = 'MAX_CONNECTIONS') +

                 (SELECT VARIABLE_VALUE FROM SESSION_VARIABLES WHERE VARIABLE_NAME = 'KEY_BUFFER_SIZE')

            )/1024/1024

            FROM SESSION_VARIABLES

            WHERE VARIABLE_NAME IN ('READ_BUFFER_SIZE', 'SORT_BUFFER_SIZE')

            2) Threads Running:

            SELECT VARIABLE_VALUE

            FROM GLOBAL_STATUS

            WHERE VARIABLE_NAME = 'THREADS_RUNNING'

            3) Key Reads:

            SELECT VARIABLE_VALUE

            FROM GLOBAL_STATUS

            WHERE VARIABLE_NAME = 'KEY_READS'

            4) Key Writes: 

            SELECT VARIABLE_VALUE

            FROM GLOBAL_STATUS

            WHERE VARIABLE_NAME = 'KEY_WRITES'

            5) Opened Tables:

            SELECT VARIABLE_VALUE

            FROM GLOBAL_STATUS

            WHERE VARIABLE_NAME = 'OPENED_TABLES'