Question about miss/hit ratio on some params
DBAsupport.com Forums - Powered by vBulletin
Results 1 to 2 of 2

Thread: Question about miss/hit ratio on some params

  1. #1
    Join Date
    Apr 2003
    Location
    Rosmalen, Netherlands.
    Posts
    73

    Question about miss/hit ratio on some params

    Hi,
    Using the followings script gives an overview of some miss/hit ratio on some parameters. What has happened with dc_table_scns and dc_qmc_cache_entries?? Who can tell me more about these two params and expain me how to deal with them??

    select parameter,
    gets,
    getmisses,
    round(getmisses/(gets+getmisses)*100,5) "miss ratio",
    round((1-(sum(getmisses)/(sum(gets)+sum(getmisses)))
    *100,5) "hit ratio"
    from v$rowcache
    where gets+getmisses <> 0
    group by parameter, gets, getmisses



    results;

    PARAMETER GETS GETMISSES miss ratio hit ratio
    -------------------------------------------------------------------------------------
    dc_files 813 10 1.21507 98.78493
    dc_users 114858 21 .01828 99.98172
    dc_objects 503592 1365 .27032 99.72968
    dc_profiles 6208 1 .01611 99.98389
    dc_segments 1085755 1115 .10259 99.89741
    dc_sequences 660 5 .75188 99.24812
    dc_usernames 70449 32 .0454 99.9546
    dc_object_ids 1046252 1072 .10236 99.89764
    dc_table_scns 1 1 50 50
    dc_global_oids 25624 147 .57041 99.42959
    dc_tablespaces 19715 12 .06083 99.93917
    dc_user_grants 8797 16 .18155 99.81845
    dc_histogram_defs 3886 684 14.96718 85.03282
    dc_qmc_cache_entries 1 1 50 50
    dc_rollback_segments 48721 11 .02257 99.97743
    dc_tablespace_quotas 233 1 .42735 99.57265


    Regards, GKramer.

  2. #2
    Join Date
    Dec 2001
    Location
    Tel-Aviv,Israel
    Posts
    233
    Hi GKramer,
    There isn't anything you can do to increase memory specifically for the dictionary cache.
    The DC* parameters from V7 are dynamicly tuned by Oracle.

    Regards,
    Nir

Posting Permissions

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


Click Here to Expand Forum to Full Width