upgrade fail/slow rollback?

  • Hello,

    I am planning to upgrade from SQL 2008 R2 SE to SQL 2012 SE in our prod env. The upgrade will be an inplace upgrade to a cluster environment from standalone. I ran the upgrade advisor and I got no unresolved issues. I already did this on our staging and test environments and upgrade was successful. But the thing is I havent noticed any performance improvement. However after upgrading it from 2008 R2 SE to 2012 SE in our production environment and after a day/two of monitoring if we notice a decrease in performance and then if we decide to rollback I will have to rely on restoring the full backups that I took before the upgrade process. But a day/two's worth of data is in the 2012 database and I will have to do a data compare and move over the new records to the 2008 R2 database. And the databases are almost a terabyte and this is going to be a slowprocess.

    Can experts please share their inputs for a better rollback plan inplace of upgrade failure or upgrade rollback.

    Thanks

    “If your actions inspire others to dream more, learn more, do more and become more, you are a leader.” -- John Quincy Adams

  • Sapen (8/25/2014)


    But a day/two's worth of data is in the 2012 database and I will have to do a data compare and move over the new records to the 2008 R2 database. And the databases are almost a terabyte and this is going to be a slowprocess.

    Yes, that's pretty much what you have to do. Rolling back something like that is not a decision to be taken lightly, it's going to involve a lot of work.

    Gail Shaw
    Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
    SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

    We walk in the dark places no others will enter
    We stand on the bridge and no one may pass
  • One other thing, after the upgrade to 2012 SE you apply the SP2 ? and the CU 1 ?

    On the CU after the SP1 of the 2012 they resolve a lot of issues with performance.

  • There is no downgrade path. It's just a question of migrating your data structures and data down to the older version. Personally, I wouldn't do it.

    If you're seeing performance issues, there's a good chance that's primarily in what would be considered edge cases. Instead of downgrading, I'd suggest tuning the queries and structures so that they perform better. There's not a massive known improvement in performance between most SQL Server versions. Rather it's incremental along with additions to behavior with the newer versions.

    "The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
    - Theodore Roosevelt

    Author of:
    SQL Server Execution Plans
    SQL Server Query Performance Tuning

  • Grant Fritchey (8/25/2014)


    Instead of downgrading, I'd suggest tuning the queries and structures so that they perform better. There's not a massive known improvement in performance between most SQL Server versions. Rather it's incremental along with additions to behavior with the newer versions.

    Seconded.

    Gail Shaw
    Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
    SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability

    We walk in the dark places no others will enter
    We stand on the bridge and no one may pass
  • You are doing an upgrade on SQL Server Version as well Standalone/Cluster changes. I would assume there will be changes to the storage as well. It will be difficult to debug performance if too many changes are made ..can be the SQL version upgrade, change in storage, network with new cluster et al. I would suggest an upgrade on your standalone to SQL Server 2012 first. Then set up the cluster et al.

Viewing 6 posts - 1 through 5 (of 5 total)

You must be logged in to reply to this topic. Login to reply