1 Reply Latest reply: Mar 2, 2014 8:09 AM by CKPT RSS

    Redo compression (LGWR)

    885820

      RDBMS: 11.2.0.3.8

       

      Hi

       

      Could anyone clarify the following:

       

      In a data guard configuration with a physical standby configured  with SYNC and LGWR  for transport settings, if redo compression is enabled - what process is actually responsible for the compression of the redo that is being transported?

       

      I'm struggling to find this information in the docs, can anyone help?

       

      Thanks

        • 1. Re: Redo compression (LGWR)
          CKPT

          885820 wrote:

           

          RDBMS: 11.2.0.3.8

           

          Hi

           

          Could anyone clarify the following:

           

          In a data guard configuration with a physical standby configured  with SYNC and LGWR  for transport settings, if redo compression is enabled - what process is actually responsible for the compression of the redo that is being transported?

           

          I'm struggling to find this information in the docs, can anyone help?

           

          Thanks

          Its good question indeed, First of all it comes under advanced compression option with extra license.

          -  it uses GNU GZIP/BZ2 methods to compress data and as i understood it applicable even for DataGuard as well. If you see in RMAN

          CONFIGURE COMPRESSION ALGORITHM 'BZIP2'; # default

          So basically for any compression it uses the same concept of course within the compression algorithm there are changes in compression methods.

          You can take a look into this URL if you are more interested to understand compression/adv compression.

          http://www.oracle.com/technetwork/database/performance/oow-adv-compression-1-130322.pdf