Results 1 to 7 of 7
  1. #1
    Join Date
    Nov 2013
    Posts
    26

    Unanswered: Log file size after archiving

    Hello, The logfile size in the db cfg parameter is different from those archived. Is it because DB2 truncates space or does any compression during archival process?

    Thank You

  2. #2
    Join Date
    Apr 2006
    Location
    Belgium
    Posts
    2,514
    Provided Answers: 11
    it is possible. arch log compression is new/available in 10.1
    Best Regards, Guy Przytula
    Database Software Consultant
    Good DBAs are not formed in a week or a month. They are created little by little, day by day. Protracted and patient effort is needed to develop good DBAs.
    Spoon feeding : To treat (another) in a way that discourages independent thought or action, as by overindulgence.
    DB2 UDB LUW Certified V7-V8-V9-V9.7-V10.1-V10.5 DB Admin - Advanced DBA -Dprop..
    Information Server Datastage Certified
    http://www.infocura.be

  3. #3
    Join Date
    Nov 2013
    Posts
    26
    Thanks for the info.
    I noticed this in V 9.5 as well.

  4. #4
    Join Date
    May 2003
    Location
    USA
    Posts
    5,737
    Quote Originally Posted by sr4230 View Post
    Thanks for the info.
    I noticed this in V 9.5 as well.
    There is no default compression of logs in 9.5, unless you have a custom logretain exit program that does compression, or some sort of compression applied after the fact.

    When you say size is different, do you realize that logfilesize is the number of 4K pages? Most of the archive log files should be that same size (and same size as active log files), but if a "archive log" occurs then it could be truncated. That could happen with an explicit "archive log" command, or some other commands or events that may force logs to be archived.
    M. A. Feldman
    IBM Certified DBA on DB2 for Linux, UNIX, and Windows
    IBM Certified DBA on DB2 for z/OS and OS/390

  5. #5
    Join Date
    Apr 2012
    Posts
    156
    Another difference that can happen is when the archive log command is issued. This will close the log even if it is not full and archive it, so it will have a different size. This happens either when you manually issue the command or at the end of an online backup. Might happen other times as well this is just when I have noticed.

  6. #6
    Join Date
    Nov 2013
    Posts
    26
    Marcus, Thats true. Its 4 K pages. Based on that I calculated. The logs are archived to EMC Networker. The networker folks say that the log size on networker is different. Could it be possible that Networker compresses when storing and decompresses when sending it to the DB2 server during retreival?

    Thanks all for your responses.

  7. #7
    Join Date
    May 2003
    Location
    USA
    Posts
    5,737
    Quote Originally Posted by sr4230 View Post
    Marcus, Thats true. Its 4 K pages. Based on that I calculated. The logs are archived to EMC Networker. The networker folks say that the log size on networker is different. Could it be possible that Networker compresses when storing and decompresses when sending it to the DB2 server during retreival?
    I don't know anything about EMC Networker, but it may be possible.

    Check the log file size in your active log directory. Should be the same as archive logs unless an archive log got truncated or is compressed.
    M. A. Feldman
    IBM Certified DBA on DB2 for Linux, UNIX, and Windows
    IBM Certified DBA on DB2 for z/OS and OS/390

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •