Performance in a single SQL Server 2014 database is slower than the restQuery Plans Change Performance Worse...

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Performance in a single SQL Server 2014 database is slower than the rest


Query Plans Change Performance Worse in SQL Server 2014Query is slow in SQL Server 2014, fast in SQL Server 2012CPU Time Slower in SQL Server 2014 than in SQL Server 2008 R2Query 100x slower in SQL Server 2014, Row Count Spool row estimate the culprit?CPU Time Slower in SQL Server 2014 than in SQL Server 2008SQL Server changes execution plan - Part 2Performance issues after moving a database to SQL Server 2014Update stats w/full scan on SQL Server 2014 uses 100% cpu, on 2008 R2, 15%Same query way faster with distinct than without distinctProblem with database migrated from SQL Server 2005 to SQL Server 2014













1















This is an interesting one... I've inherited a SQL Server for our ERP system. It currently runs SQL Server 2014 CU 10. I've done some best practices and performance tuning on it and server performance has gone from the toilet to acceptable levels.



However, I have a query/stored procedure that when run on one specific database takes up to 7 minutes to run while on similar databases (there are 6 others, 1 has MUCH more data) it takes maybe 30 seconds tops. I've checked file permissions, I've diff'ed the SP's, I've checked database settings and I can't find anything that points to the slowness.



Does anyone have any recommendations on what I should be looking at?



I was able to get an execution plan excerpt from the databases (2MB limit on Brent's site).




  • This is the execution plan on the "bad" database.

  • This is the execution plan for the "good" database.


The only difference between the two is the "good" DB doesn't have the current data (i.e. older copy).



I've double checked my server settings in both environments & they appear to be identical. The only thing I can confirm so far is if I drop the "bad" database's compatibility level down to 2008 it performs perfectly. Yet the same database inside the dev environment at 2014 runs flawlessly.



There is a possible coding error in the stored procedure I'm checking. I can't get anything out using CTRL+L but I do if I attempt to run it.




  • The databases are not replicated. The server is a VM and the drives are all shared.

  • I've done a table comparison & they are identical. Compatibility level is the same as well as are indexes and stats.


I'll update again when I know more.










share|improve this question
















bumped to the homepage by Community 16 mins ago


This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.






migrated from stackoverflow.com Mar 22 '18 at 21:09


This question came from our site for professional and enthusiast programmers.























    1















    This is an interesting one... I've inherited a SQL Server for our ERP system. It currently runs SQL Server 2014 CU 10. I've done some best practices and performance tuning on it and server performance has gone from the toilet to acceptable levels.



    However, I have a query/stored procedure that when run on one specific database takes up to 7 minutes to run while on similar databases (there are 6 others, 1 has MUCH more data) it takes maybe 30 seconds tops. I've checked file permissions, I've diff'ed the SP's, I've checked database settings and I can't find anything that points to the slowness.



    Does anyone have any recommendations on what I should be looking at?



    I was able to get an execution plan excerpt from the databases (2MB limit on Brent's site).




    • This is the execution plan on the "bad" database.

    • This is the execution plan for the "good" database.


    The only difference between the two is the "good" DB doesn't have the current data (i.e. older copy).



    I've double checked my server settings in both environments & they appear to be identical. The only thing I can confirm so far is if I drop the "bad" database's compatibility level down to 2008 it performs perfectly. Yet the same database inside the dev environment at 2014 runs flawlessly.



    There is a possible coding error in the stored procedure I'm checking. I can't get anything out using CTRL+L but I do if I attempt to run it.




    • The databases are not replicated. The server is a VM and the drives are all shared.

    • I've done a table comparison & they are identical. Compatibility level is the same as well as are indexes and stats.


    I'll update again when I know more.










    share|improve this question
















    bumped to the homepage by Community 16 mins ago


    This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.






    migrated from stackoverflow.com Mar 22 '18 at 21:09


    This question came from our site for professional and enthusiast programmers.





















      1












      1








      1








      This is an interesting one... I've inherited a SQL Server for our ERP system. It currently runs SQL Server 2014 CU 10. I've done some best practices and performance tuning on it and server performance has gone from the toilet to acceptable levels.



      However, I have a query/stored procedure that when run on one specific database takes up to 7 minutes to run while on similar databases (there are 6 others, 1 has MUCH more data) it takes maybe 30 seconds tops. I've checked file permissions, I've diff'ed the SP's, I've checked database settings and I can't find anything that points to the slowness.



      Does anyone have any recommendations on what I should be looking at?



      I was able to get an execution plan excerpt from the databases (2MB limit on Brent's site).




      • This is the execution plan on the "bad" database.

      • This is the execution plan for the "good" database.


      The only difference between the two is the "good" DB doesn't have the current data (i.e. older copy).



      I've double checked my server settings in both environments & they appear to be identical. The only thing I can confirm so far is if I drop the "bad" database's compatibility level down to 2008 it performs perfectly. Yet the same database inside the dev environment at 2014 runs flawlessly.



      There is a possible coding error in the stored procedure I'm checking. I can't get anything out using CTRL+L but I do if I attempt to run it.




      • The databases are not replicated. The server is a VM and the drives are all shared.

      • I've done a table comparison & they are identical. Compatibility level is the same as well as are indexes and stats.


      I'll update again when I know more.










      share|improve this question
















      This is an interesting one... I've inherited a SQL Server for our ERP system. It currently runs SQL Server 2014 CU 10. I've done some best practices and performance tuning on it and server performance has gone from the toilet to acceptable levels.



      However, I have a query/stored procedure that when run on one specific database takes up to 7 minutes to run while on similar databases (there are 6 others, 1 has MUCH more data) it takes maybe 30 seconds tops. I've checked file permissions, I've diff'ed the SP's, I've checked database settings and I can't find anything that points to the slowness.



      Does anyone have any recommendations on what I should be looking at?



      I was able to get an execution plan excerpt from the databases (2MB limit on Brent's site).




      • This is the execution plan on the "bad" database.

      • This is the execution plan for the "good" database.


      The only difference between the two is the "good" DB doesn't have the current data (i.e. older copy).



      I've double checked my server settings in both environments & they appear to be identical. The only thing I can confirm so far is if I drop the "bad" database's compatibility level down to 2008 it performs perfectly. Yet the same database inside the dev environment at 2014 runs flawlessly.



      There is a possible coding error in the stored procedure I'm checking. I can't get anything out using CTRL+L but I do if I attempt to run it.




      • The databases are not replicated. The server is a VM and the drives are all shared.

      • I've done a table comparison & they are identical. Compatibility level is the same as well as are indexes and stats.


      I'll update again when I know more.







      sql-server sql-server-2014 query-performance






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited Mar 26 '18 at 16:42









      Paul White

      52.9k14281457




      52.9k14281457










      asked Mar 22 '18 at 14:20









      thatstevecenathatstevecena

      83




      83





      bumped to the homepage by Community 16 mins ago


      This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.







      bumped to the homepage by Community 16 mins ago


      This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.






      migrated from stackoverflow.com Mar 22 '18 at 21:09


      This question came from our site for professional and enthusiast programmers.









      migrated from stackoverflow.com Mar 22 '18 at 21:09


      This question came from our site for professional and enthusiast programmers.
























          2 Answers
          2






          active

          oldest

          votes


















          0














          Also try to look the estimated execution plan. Besides, while executing your SP open a new session and look for wait_stats. That will give you more hints on what is your query waiting on.






          share|improve this answer
























          • Thanks to all. I'm still working on the execution plan. This is an of-the-shelf ERP system with custom stored procedures added for functionality. I need to talk to the application manager as this is one of the queries she wrote. If I try to get an execution plan using CTRL+L I get a coding error. However, if I just execute the query outright it runs ok. I should have some kind of update today.

            – thatstevecena
            Mar 26 '18 at 11:01











          • Ok; I was able to get an execution plan excerpt from the databases (2MB limit on Brent's site). This is the [execution plan on the "bad" database][1]. This is the [execution plan for the "good" database][2]. The only difference between the two is the "good" DB doesn't have the current data. There is a possible coding error in the stored procedure I'm checking. I can't get anything out using CTRL+L but I do if I attempt to run it. [1]: brentozar.com/pastetheplan/?id=rJeXYYU9M [2]: brentozar.com/pastetheplan/?id=r1Kh9KI5G

            – thatstevecena
            Mar 27 '18 at 12:05











          • I'm still not having any luck. If I compare the query execution plans between those that work and the one that doesn't they're almost identical except for warnings on various commands. As I have a working copy of the DB at the latest revision, it's looking like something must have gotten corrupted when I upgraded the database from 2005 to 2014. I'm going to keep at it as performance is just killing this one department.

            – thatstevecena
            Apr 2 '18 at 12:28






          • 1





            It has turned out that the performance issues were not in fact related to just this one database, but a much wider spread issue. I apologize for the lack of updates.

            – thatstevecena
            May 17 '18 at 19:12



















          0














          SQL Server 2014 cardinality estimator can cause performance issue sometime. Run your query by adding OPTION(QUERYTRACEON 9481) at end of your query and check if this is issue with Cardinatliy Estimator.



          Refer https://www.brentozar.com/archive/2014/04/sql-2014-cardinality-estimator-eats-bad-tsql-breakfast/






          share|improve this answer























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            2 Answers
            2






            active

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            2 Answers
            2






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            0














            Also try to look the estimated execution plan. Besides, while executing your SP open a new session and look for wait_stats. That will give you more hints on what is your query waiting on.






            share|improve this answer
























            • Thanks to all. I'm still working on the execution plan. This is an of-the-shelf ERP system with custom stored procedures added for functionality. I need to talk to the application manager as this is one of the queries she wrote. If I try to get an execution plan using CTRL+L I get a coding error. However, if I just execute the query outright it runs ok. I should have some kind of update today.

              – thatstevecena
              Mar 26 '18 at 11:01











            • Ok; I was able to get an execution plan excerpt from the databases (2MB limit on Brent's site). This is the [execution plan on the "bad" database][1]. This is the [execution plan for the "good" database][2]. The only difference between the two is the "good" DB doesn't have the current data. There is a possible coding error in the stored procedure I'm checking. I can't get anything out using CTRL+L but I do if I attempt to run it. [1]: brentozar.com/pastetheplan/?id=rJeXYYU9M [2]: brentozar.com/pastetheplan/?id=r1Kh9KI5G

              – thatstevecena
              Mar 27 '18 at 12:05











            • I'm still not having any luck. If I compare the query execution plans between those that work and the one that doesn't they're almost identical except for warnings on various commands. As I have a working copy of the DB at the latest revision, it's looking like something must have gotten corrupted when I upgraded the database from 2005 to 2014. I'm going to keep at it as performance is just killing this one department.

              – thatstevecena
              Apr 2 '18 at 12:28






            • 1





              It has turned out that the performance issues were not in fact related to just this one database, but a much wider spread issue. I apologize for the lack of updates.

              – thatstevecena
              May 17 '18 at 19:12
















            0














            Also try to look the estimated execution plan. Besides, while executing your SP open a new session and look for wait_stats. That will give you more hints on what is your query waiting on.






            share|improve this answer
























            • Thanks to all. I'm still working on the execution plan. This is an of-the-shelf ERP system with custom stored procedures added for functionality. I need to talk to the application manager as this is one of the queries she wrote. If I try to get an execution plan using CTRL+L I get a coding error. However, if I just execute the query outright it runs ok. I should have some kind of update today.

              – thatstevecena
              Mar 26 '18 at 11:01











            • Ok; I was able to get an execution plan excerpt from the databases (2MB limit on Brent's site). This is the [execution plan on the "bad" database][1]. This is the [execution plan for the "good" database][2]. The only difference between the two is the "good" DB doesn't have the current data. There is a possible coding error in the stored procedure I'm checking. I can't get anything out using CTRL+L but I do if I attempt to run it. [1]: brentozar.com/pastetheplan/?id=rJeXYYU9M [2]: brentozar.com/pastetheplan/?id=r1Kh9KI5G

              – thatstevecena
              Mar 27 '18 at 12:05











            • I'm still not having any luck. If I compare the query execution plans between those that work and the one that doesn't they're almost identical except for warnings on various commands. As I have a working copy of the DB at the latest revision, it's looking like something must have gotten corrupted when I upgraded the database from 2005 to 2014. I'm going to keep at it as performance is just killing this one department.

              – thatstevecena
              Apr 2 '18 at 12:28






            • 1





              It has turned out that the performance issues were not in fact related to just this one database, but a much wider spread issue. I apologize for the lack of updates.

              – thatstevecena
              May 17 '18 at 19:12














            0












            0








            0







            Also try to look the estimated execution plan. Besides, while executing your SP open a new session and look for wait_stats. That will give you more hints on what is your query waiting on.






            share|improve this answer













            Also try to look the estimated execution plan. Besides, while executing your SP open a new session and look for wait_stats. That will give you more hints on what is your query waiting on.







            share|improve this answer












            share|improve this answer



            share|improve this answer










            answered Mar 23 '18 at 19:44









            Pablo JavierPablo Javier

            594




            594













            • Thanks to all. I'm still working on the execution plan. This is an of-the-shelf ERP system with custom stored procedures added for functionality. I need to talk to the application manager as this is one of the queries she wrote. If I try to get an execution plan using CTRL+L I get a coding error. However, if I just execute the query outright it runs ok. I should have some kind of update today.

              – thatstevecena
              Mar 26 '18 at 11:01











            • Ok; I was able to get an execution plan excerpt from the databases (2MB limit on Brent's site). This is the [execution plan on the "bad" database][1]. This is the [execution plan for the "good" database][2]. The only difference between the two is the "good" DB doesn't have the current data. There is a possible coding error in the stored procedure I'm checking. I can't get anything out using CTRL+L but I do if I attempt to run it. [1]: brentozar.com/pastetheplan/?id=rJeXYYU9M [2]: brentozar.com/pastetheplan/?id=r1Kh9KI5G

              – thatstevecena
              Mar 27 '18 at 12:05











            • I'm still not having any luck. If I compare the query execution plans between those that work and the one that doesn't they're almost identical except for warnings on various commands. As I have a working copy of the DB at the latest revision, it's looking like something must have gotten corrupted when I upgraded the database from 2005 to 2014. I'm going to keep at it as performance is just killing this one department.

              – thatstevecena
              Apr 2 '18 at 12:28






            • 1





              It has turned out that the performance issues were not in fact related to just this one database, but a much wider spread issue. I apologize for the lack of updates.

              – thatstevecena
              May 17 '18 at 19:12



















            • Thanks to all. I'm still working on the execution plan. This is an of-the-shelf ERP system with custom stored procedures added for functionality. I need to talk to the application manager as this is one of the queries she wrote. If I try to get an execution plan using CTRL+L I get a coding error. However, if I just execute the query outright it runs ok. I should have some kind of update today.

              – thatstevecena
              Mar 26 '18 at 11:01











            • Ok; I was able to get an execution plan excerpt from the databases (2MB limit on Brent's site). This is the [execution plan on the "bad" database][1]. This is the [execution plan for the "good" database][2]. The only difference between the two is the "good" DB doesn't have the current data. There is a possible coding error in the stored procedure I'm checking. I can't get anything out using CTRL+L but I do if I attempt to run it. [1]: brentozar.com/pastetheplan/?id=rJeXYYU9M [2]: brentozar.com/pastetheplan/?id=r1Kh9KI5G

              – thatstevecena
              Mar 27 '18 at 12:05











            • I'm still not having any luck. If I compare the query execution plans between those that work and the one that doesn't they're almost identical except for warnings on various commands. As I have a working copy of the DB at the latest revision, it's looking like something must have gotten corrupted when I upgraded the database from 2005 to 2014. I'm going to keep at it as performance is just killing this one department.

              – thatstevecena
              Apr 2 '18 at 12:28






            • 1





              It has turned out that the performance issues were not in fact related to just this one database, but a much wider spread issue. I apologize for the lack of updates.

              – thatstevecena
              May 17 '18 at 19:12

















            Thanks to all. I'm still working on the execution plan. This is an of-the-shelf ERP system with custom stored procedures added for functionality. I need to talk to the application manager as this is one of the queries she wrote. If I try to get an execution plan using CTRL+L I get a coding error. However, if I just execute the query outright it runs ok. I should have some kind of update today.

            – thatstevecena
            Mar 26 '18 at 11:01





            Thanks to all. I'm still working on the execution plan. This is an of-the-shelf ERP system with custom stored procedures added for functionality. I need to talk to the application manager as this is one of the queries she wrote. If I try to get an execution plan using CTRL+L I get a coding error. However, if I just execute the query outright it runs ok. I should have some kind of update today.

            – thatstevecena
            Mar 26 '18 at 11:01













            Ok; I was able to get an execution plan excerpt from the databases (2MB limit on Brent's site). This is the [execution plan on the "bad" database][1]. This is the [execution plan for the "good" database][2]. The only difference between the two is the "good" DB doesn't have the current data. There is a possible coding error in the stored procedure I'm checking. I can't get anything out using CTRL+L but I do if I attempt to run it. [1]: brentozar.com/pastetheplan/?id=rJeXYYU9M [2]: brentozar.com/pastetheplan/?id=r1Kh9KI5G

            – thatstevecena
            Mar 27 '18 at 12:05





            Ok; I was able to get an execution plan excerpt from the databases (2MB limit on Brent's site). This is the [execution plan on the "bad" database][1]. This is the [execution plan for the "good" database][2]. The only difference between the two is the "good" DB doesn't have the current data. There is a possible coding error in the stored procedure I'm checking. I can't get anything out using CTRL+L but I do if I attempt to run it. [1]: brentozar.com/pastetheplan/?id=rJeXYYU9M [2]: brentozar.com/pastetheplan/?id=r1Kh9KI5G

            – thatstevecena
            Mar 27 '18 at 12:05













            I'm still not having any luck. If I compare the query execution plans between those that work and the one that doesn't they're almost identical except for warnings on various commands. As I have a working copy of the DB at the latest revision, it's looking like something must have gotten corrupted when I upgraded the database from 2005 to 2014. I'm going to keep at it as performance is just killing this one department.

            – thatstevecena
            Apr 2 '18 at 12:28





            I'm still not having any luck. If I compare the query execution plans between those that work and the one that doesn't they're almost identical except for warnings on various commands. As I have a working copy of the DB at the latest revision, it's looking like something must have gotten corrupted when I upgraded the database from 2005 to 2014. I'm going to keep at it as performance is just killing this one department.

            – thatstevecena
            Apr 2 '18 at 12:28




            1




            1





            It has turned out that the performance issues were not in fact related to just this one database, but a much wider spread issue. I apologize for the lack of updates.

            – thatstevecena
            May 17 '18 at 19:12





            It has turned out that the performance issues were not in fact related to just this one database, but a much wider spread issue. I apologize for the lack of updates.

            – thatstevecena
            May 17 '18 at 19:12













            0














            SQL Server 2014 cardinality estimator can cause performance issue sometime. Run your query by adding OPTION(QUERYTRACEON 9481) at end of your query and check if this is issue with Cardinatliy Estimator.



            Refer https://www.brentozar.com/archive/2014/04/sql-2014-cardinality-estimator-eats-bad-tsql-breakfast/






            share|improve this answer




























              0














              SQL Server 2014 cardinality estimator can cause performance issue sometime. Run your query by adding OPTION(QUERYTRACEON 9481) at end of your query and check if this is issue with Cardinatliy Estimator.



              Refer https://www.brentozar.com/archive/2014/04/sql-2014-cardinality-estimator-eats-bad-tsql-breakfast/






              share|improve this answer


























                0












                0








                0







                SQL Server 2014 cardinality estimator can cause performance issue sometime. Run your query by adding OPTION(QUERYTRACEON 9481) at end of your query and check if this is issue with Cardinatliy Estimator.



                Refer https://www.brentozar.com/archive/2014/04/sql-2014-cardinality-estimator-eats-bad-tsql-breakfast/






                share|improve this answer













                SQL Server 2014 cardinality estimator can cause performance issue sometime. Run your query by adding OPTION(QUERYTRACEON 9481) at end of your query and check if this is issue with Cardinatliy Estimator.



                Refer https://www.brentozar.com/archive/2014/04/sql-2014-cardinality-estimator-eats-bad-tsql-breakfast/







                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered Apr 7 '18 at 15:05









                ASPASP

                1363




                1363






























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