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Database Mirroring doubt RRS feed

  • Question

  • My question is

    Who will send data from Priniciple server to Mirror server ?

    I know end point to communication channel establish from Priniciple to Mirror. I would like to know who will send the data from P to M. I appreiciate your respose.

     

    ThanksQ

    SNS

     

    • Moved by Tom Phillips Thursday, July 7, 2011 4:28 PM Database Mirror question (From:SQL Server Database Engine)
    Thursday, July 7, 2011 10:03 AM

All replies

  • From BOL: http://msdn.microsoft.com/en-us/library/ms189901.aspx

    Threads Created for a Database Mirroring Session

    The kinds of threads that a server instance creates for a database mirroring session depend partly on the mirroring roles that the server instance is performing. A given session has some or all of the following threads:
    - One global thread for database mirroring communications. This thread is started by Service Broker.

    If the server instance is acting as a mirroring partner (whether it is the principal server or mirror server):
    - One thread per mirrored database for event processing.
    - One thread per mirrored database for asynchronous tasks (such as log send or log write) that would otherwise block the event thread.

    Whenever the instance is acting as a mirror server:
    - One redo manager thread, which submits log for redo, performs page read-ahead, lock reacquisition, and so on.

    In SQL Server Standard, one redo thread per mirror database, or in SQL Server Enterprise, one redo thread per mirror database for every four CPUs. These threads perform the actual log redo.

    If the instance is acting as a witness:
    - One global thread for processing the witness messages for all mirroring sessions in which the instance is acting as the witness.

    • Proposed as answer by Satya SKJMVP Friday, July 8, 2011 12:12 PM
    Thursday, July 7, 2011 10:53 AM
  • My question is

    Who will send data from Priniciple server to Mirror server ?

    I know end point to communication channel establish from Priniciple to Mirror. I would like to know who will send the data from P to M. I appreiciate your respose.

     

    ThanksQ

    SNS

     


    ITS SERVICE BROKER ...
    Abhay Chaudhary OCP 9i, MCTS/MCITP (SQL Server 2005, 2008, 2005 BI) ms-abhay.blogspot.com/
    Thursday, July 7, 2011 3:48 PM
  • SQL Server Engine send modified rows from P to M... 
    Best Regards, Uri Dimant SQL Server MVP http://dimantdatabasesolutions.blogspot.com/ http://sqlblog.com/blogs/uri_dimant/
    • Proposed as answer by Satya SKJMVP Friday, July 8, 2011 12:12 PM
    Thursday, July 7, 2011 6:50 PM
  • Yes its is SQL Server Engine which send new or modified rows from Principal to Mirror and vice versa in case any currupted pages found in principal from SQL 2008 later versions.... mostly its down to DB Mirror back ground service which started once you completed mirroring configuration.

    In high safety mode application won't get commit acknowledge back until committed transaction writes principal log as well as mirror log drive. where as high performance mode commit acknowledge sent back with out wait to write commited transaction to mirror log drive....


    http://uk.linkedin.com/in/ramjaddu
    Tuesday, July 12, 2011 8:53 AM