High swaps in ST02

Hi All,
Does anyone know what should I do if I found that my system has high buffer swaps. The hit ratio is good enough(99%).
Thanks & Regards,
Casper

Hi casper,
a high Hit ratio is not ALWAYS a good thing. Is it possible that a very large table is buffered constantly in the buffer, which is accessed frequently, as a result of which, you get a high hit ratio, but there is no space left for other tables.
Please check if the ratio of Buffer Gets : User Calls if it is greater than 15..
Ifi t is, then you have some expensive select statements running and you need to tune those.
Hope this helps.
Regards
Shantanu

Similar Messages

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    Hello All,
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    Efficiency       
    HITRATIO          %        42
    HITS                    9,645
    REQUESTS               22,790
    DB access quality %        42
    DB access              13,136
    DB access saved         9,645
    Reorgs                      0
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    Available        KB     7,500
    Used             KB     1,053
    Free             KB     6,447
    Directory entries
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    Used                    3,801
    Free                    6,199
    Swaps            
    Objects swapped         9,335
    Frames swapped              0
    Resets            Total                       0
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                       HITS                   10,243
                       REQUESTS               23,731
                       DB access quality %        43
                       DB access              13,488
                       DB access saved        10,243
                       Reorgs                      0
    Size              Allocated        KB    42,906
                       Available        KB    41,500
                       Used             KB     4,717
                       Free             KB    36,783
    Directory entries Available              11,250
                       Used                    9,759
                       Free                    1,491
    Swaps             Objects swapped         3,728
                       Frames swapped              0
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    Message was edited by:
            ganesh reddy kanthala

    Hi
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    JA,
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  • How to reduce Swaps in ST02

    Dear Experts,
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    Initial records
    Program
    CUA
    Screen
    Tables
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    Single record
    Export/import
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    ECC 5.0
    Oracle Release 9.2.0.6.0
    Physical mem avail  Kb    16,764,976
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    Hi,
    Please click [buffers|http://help.sap.com/erp2005_ehp_04/helpdata/EN/c4/3a6e98505211d189550000e829fbbd/frameset.htm] for information.
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    zcsa/presentation_buffer_area u2013 Total screen buffer size in KB.
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    Role and paging buffer.
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    rdisp/PG_SHM u2013 For paging buffer
    Calendar Buffer
    zcsa/calendar_area
    With Regards,
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  • Which Process using high Swap

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    prstat -s size
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  • Swaps in ST02

    Hi all,
    We just increased the program buffer from 850 MB to 950 MB 3 weeks back and then to 1050 MB a week back.The system looks normal for a few days and then again i can see the swpas increaing.We already have 16 GB of memory on a 64bit Win NT platform.The DB is db2 v 8.1.5......
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    Also the Nametab ,Table definition,   Short NTAB,Field definition, Initial records  buffers  are showing a lot of swaps ..
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    rsdb/ntab/entrycount = 70000
    rsdb/ntab/ftabsize  = 62500 KB
    rsdb/ntab/sntabsize = 2500 KB
    rsdb/ntab/irbdsize = 30 000 KB
    Which values should i change...please suggest.....

    Hi Kalyan and Juan,
    thanks.. for replying...
    The program buffer is showing about 18000 swaps...
    also the
    Field definition buffer shows 151,000 buffer swaps,
    Short NTAB = 19,418 buffer swaps and
    initial records buffer = 54,158 buffer swaps.
    We just increased the program buffer from 850 MB to 950 MB 3 weeks back and then to 1050 MB a week back.The system looks normal for a few days and then again i can see the swpas increaing.We already have 16 GB of memory on a 64bit Win NT platform.The DB is db2 v 8.1.5......
    Should there be something that has to be changed in the DB2 side, or should i again increae it. also i read somewhere that increasing too much program buffer area willl lead to buffer fragmentation .
    I am not sure . please suggest if and to what extent i can increase....
    Also the Nametab ,Table definition, Short NTAB,Field definition, Initial records buffers are showing a lot of swaps ..
    I looked at the relevant parameters:
    rsdb/ntab/entrycount = 70000
    rsdb/ntab/ftabsize = 62500 KB
    rsdb/ntab/sntabsize = 2500 KB
    rsdb/ntab/irbdsize = 30 000 KB

  • Swaps values showing in RED -TCODE ST02

    Hi All,
    When I checked the ST02 transaction  value of "SWAPS" for program buffer,CUA buffer,screen buffer, Tables generic key buffer and export/import buffer are showing in "RED" colour.
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    Program           99.88         900000        0.36             19541
    CUA                99.9           10,000         1.27             37960
    export/import    94.33         40,000         29.10          750,676
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    Thanks in advance
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    Prashant.

    Dear Prashant,
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  • St02 swaps red

    Hi all,
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      Field description       96.55        32,344        5,702    19.01        30,000       21,404    71.35       254,965      263,737
      Short NTAB              99.74         3,438        2,137    85.48         7,500        5,803    77.37             0        1,697
      Initial records         96.18         5,438          177     3.93         7,500          654     8.72        96,328      103,175
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    Screen                    99.86        25,391       18,314    72.89         4,500        4,016    89.24             0          516
    Calendar                 100.00           488          394    82.08           200           95    47.50             0          105
    OTR                      100.00         4,096        3,531   100.00         2,000        2,000   100.00             0            0
    Tables
      Generic key             99.99        99,023        9,072     9.44        13,000          998     7.68            12       59,612
      Single record           97.10       100,000       75,927    76.12         1,000          876    87.60             0      171,530
    Export/import             66.42        20,000       11,764    81.85        20,000       18,587    92.94             0            0
    Exp./Imp. SHM             16.95         4,096        3,490    98.84         2,000        1,999    99.95             0            0

    Hi Ambarish,
    These are the values which u can take as reference
    rsdb/ntab/entrycount               30000                       
      rsdb/ntab/irbdsize                  4000
      rsdb/ntab/sntabsize                 2500
      rsdb/cua/buffersize                 5000
      sap/bufdir_entries                 10000
       zcsa/table_buffer_area          50000000
      zcsa/db_max_buftab                 10000
      rtbb/buffer_length                 30000
       rtbb/max_tables                      500
    Release 4.0/4.5:
       rsdb/obj/buffersize              4096          (kB)             
       rsdb/obj/max_objects            5000          (buffer entries)
       rsdb/obj/large_object_size       8192          (Byte)           
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       rsdb/obj/buffersize            20000            (kB)          
       rsdb/obj/max_objects            20000                         
       rsdb/obj/large_object_size       8192          (Byte)    
    extend the buffers to 30 -40%  this may help you
    Regards'
      Zia

  • ST02 ---Swaps

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