Improving Tape Speed

  • All,

    I am running into problem with my SQL server tape drive.  It is a HP DLT tape drive and it is running very slow.  We are in the process of troubleshooting any hardware related issues.  The database files are taking a long time to backup and even small files are taking a long time. 

    Is there anything I can do speed up the backups?  Are there any tools out there?  Any suggestions anybody may have???

    Thanks and appreciate all your help,

    Raj

  • Are you using an SQL plugin for a third party tool, like Backup Exec with the SQL add-on?

    If so, that might be a problem.  I would recommend you backup the databases to files, then backup the database backup files.

    Have you tried to backup just a few text files to the DTL drive?  Does that take a long time too?  If text files take a long time, then it is the tape drive.

     

  • Hi,

    No, I am not using 3rd party tools like Backup Exec.  Just using the backup functionality provided by SQL Server.  There was some thought about moving towards like Veritas or Brightstor.  Nothing is finalized...  I got to figure out why this thing is running so slow...

    We are trying to check on the speed of the backup files through Windows Backup Tools.  On the Dell, the speeds were about the same compared with Windows and SQL Server.  I was planning to do do the same on the HP drive today. 

    On backing it up to file first and then running the backups, how would you handle the transaction log backups if you have set up a maintenance plan.  Do you backup the same files over and over again?  Do you use the windows scheduler to schedule the backups?

    Thanks,

  • Most People I know Backup to Disk First! then to tape.

    And yes, you can use windows scheduler to grab a folder (THE BACKUP Folder) periodically.

     


    * Noel

  • Are you using the WITH NOREWIND option?  This can make a huge difference when backing up multiple databases onto the same tape.  Only want to rewind when done for the day/session/tape/whatever.

  • Acutually, yes I am using the NOREWIND option.

    BACKUP DATABASE [Test]

    TO Tape_001 WITH  NOINIT , 

    NOREWIND , RETAINDAYS = 21,  

    NAME = N'Test Complete Database Backup', 

    NOSKIP ,  DESCRIPTION = N'Complete Backup Of Test Databse, 

    NOFORMAT , 

    MEDIANAME = N'Tape Rotation 001'

    I know NOINIT is optional or is the default.  I wanted to check for header because I don't want to overwrite a backup (a needed one).  Or should I just check for the first backup run for that particular tape...

    Thanks,

    Raj

  • That looks good to me, maybe you do have physical problem w/the tape or the connection to it.

    The RETAINDAYS should take care of not overwriting, shouldn't it?  Sometimes we manually want to check what's on a tape, though, and HEADERONLY is pretty slow, maybe 20mins.  Because of way we are organizing backups onto tapes, we were able to write info into the MEDIANAME at time of formatting (which we do for the 1st backup on a given tape) that tells us what's on the tape, so now we can quickly assess what's on a tape by LABELONLY, which finishes in about 30sec for us. 

  • Check if you have correct version of drivers loaded.

    What is backup speed/time on same tape, when you use windows backup to backup equivalent sized OS files (can be other than ur database files) ?

    also note the time taken in backup on Tape Drive on a test tape where u specify INIT, (this would be a first backup on that tape).

    This is just to check amount of time taken by TAPE when it is writing to  start of tape and when it is forwarding itslef and reaching at a writeable section somewhere towards end of tape.

    do post ur results.

    -- amit


    -- Amit



    "There is no 'patch' for stupidity."



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