Skip to Content

About transaction logs

Can you tell me about transaction log space? how does it gets full? How is it related to performance?

Add a comment
10|10000 characters needed characters exceeded

Related questions

2 Answers

  • Best Answer
    Posted on Mar 18, 2009 at 07:16 AM

    RUshikesh,

    If you are referring to the DB logs that are captured....

    What is a transaction log :

    A transaction log s a log of all database related actvities - the transaction log tells you all the changes that have happened to the database

    Why is it required :

    A transaction log can be used to restore a database and when you apply transaction logs to a databse - it does all the activities on the target database agains.

    Performance :

    If the log gets full - then you cannot do any changes to the database and the system will stop working because the log is full.

    Add a comment
    10|10000 characters needed characters exceeded

  • author's profile photo Former Member
    Former Member
    Posted on Mar 18, 2009 at 06:14 AM

    Hi,

    Monitoring the SAP Log Disk

    Use

    The size of the transaction log must be checked regularly to work out how much free space is available on the log disk. There should always be enough free space to allow the next file extension. When the SAP system has been installed the autogrow increment is set. At least the size of this increment should be available on the log disk to permit the next file extension. If less space is available and the transaction log file fills up, the SAP system will come to a standstill.

    Ideally, the transaction log should never be filled to more than 60-70%. If the transaction log regularly exceeds this level between 2 transaction log backups, the transaction log must be saved at more frequent time intervals.

    The size of the log can be assessed on the basis of information given for completed backups in the SAP transaction for Backup and Restore Information.

    Procedure:

    1. To access the transaction for Backup Restore Information choose CCMS ® DB Administration ® Backup logs.

    Alternatively, enter the transaction code DB12.

    The initial screen of the monitor CCMS Monitoring Tool u2013 DB12 (Backup Restore Information) appears.

    2. Choose Backup history and then Logs Backup.

    3. A result list appears. Find the largest transaction log backup of the past week. Select a row and then History info to find out the number of pages that were processed during the backup. To work out the amount of space used in the transaction log, multiply the number of dumped pages by 8 KB. You can then work out how much free space is left on the transaction log disk.

    If you use a RAID1 disk system exclusively for the SAP transaction log and create hourly log backups, you will rarely encounter space problems. The SAP log file is initially created with a size of 1 GB. The smallest disk normally has 9 GB space and the log file can therefore grow to 9 GB.

    Hope it Helps

    Srini

    Add a comment
    10|10000 characters needed characters exceeded

Before answering

You should only submit an answer when you are proposing a solution to the poster's problem. If you want the poster to clarify the question or provide more information, please leave a comment instead, requesting additional details. When answering, please include specifics, such as step-by-step instructions, context for the solution, and links to useful resources. Also, please make sure that you answer complies with our Rules of Engagement.
You must be Logged in to submit an answer.

Up to 10 attachments (including images) can be used with a maximum of 1.0 MB each and 10.5 MB total.