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Former Member

Data Buffer Quality is very low

Hi All,

We have 3 instances in one system,which databuffer quality of

2 systems are about 91% and Dev system is very low i.e 75%.

The physical memeory is 16 gb.The hit ratios of all the systems are 99%.Can anybody suggest for the buffer quality to be increased to 95%.

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4 Answers

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    Former Member
    Sep 05, 2008 at 09:15 AM

    Hi kranthi,

    Buffer quality refers to database buffering (st04).

    Look at below link.

    http://help.sap.com/erp2005_ehp_03/helpdata/EN/c4/3a71fc505211d189550000e829fbbd/frameset.htm

    Regards

    Ashok

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    Former Member
    Sep 05, 2008 at 12:03 PM

    Hi

    Kranthi

    The link given by ashok is very helpful,

    In addition to that, the buffer quality indicates the access to the database by the users, i.e objects picked from the data buffer,

    and if the objects are directly read from the database (not from the buffer) then the buffer quality will get down, if u access for the next time it will pick from the buffer.

    Its time to ask u one question

    Does this show for a long time?

    Based upon this we can proceed

    Regards

    Bhaskar

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  • Sep 05, 2008 at 04:00 PM

    Hi

    Data buffer quality is one of the performance indicator that we check if high database time is observed in the system.

    Data buffer quality represents how much data is read from the buffer. Data buffers are used for faster accesses and to decrease the i/o on the system. If the data is read from the database it will incur I/O leading to low buffer quality.

    Data buffer quality can be low because of two reasons:

    1. Either the data buffer size is small.

    In case first check whether you have free memory available if you have increase the size of data buffer.

    2. Either due to expensive SQL.

    In case check for other counters as you mentioned like reads/user call less than 20 and hit ratio.

    If these counters are outside the threshold values then you tune some expensive sql to improve the database performance counters.

    Hope this helps!!

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    Former Member
    Sep 05, 2008 at 04:42 PM

    Hi Bhaskar,

    Thank you for the response.Yes it is showing from the longtime

    Please do the needful

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