System Statistics

Question

Hi,
I am moving from HPUX PARISK to HPUX iTANIUM my 10203 instance.
I am planing to gather system and dictionary stats based on oracle metalink note :
How to gather statistics on SYS objects and fixed_objects? (Doc ID 457926.1)
To gather the dictionary stats:-
SQL> EXEC DBMS_STATS.GATHER_SCHEMA_STATS ('SYS');
SQL> exec DBMS_STATS.GATHER_DATABASE_STATS (gather_sys=>TRUE);
SQL> EXEC DBMS_STATS.GATHER_DICTIONARY_STATS;
Gather_fixed_objects_stats also gathers statistics for dynamic tables e.g. the X$ tables which
loaded in SGA during the startup. Gathering statistics for fixed objects would normally be recommeded if poor performance is encountered while querying dynamic views e.g. V$ views.
Since fixed objects record current database activity; statistics gathering should be done when database has a representative load so that the statistics reflect the normal database activity .
To gather the fixed objects stats use:- EXEC DBMS_STATS.GATHER_FIXED_OBJECTS_STATS; I have two questions :
1. Show i run all the 4 commands mention above in order collect system stats ?
2. How can i rollback those statistics in case of poort performance against the dictionary table ?
Thanks
Yoav

Answer 1

SQL> exec dbms_stats.create_stat_table(user,'STAT_TIMESTAMP');
PL/SQL procedure successfully completed.
SQL> exec dbms_stats.export_system_stats('STAT_TIMESTAMP');
PL/SQL procedure successfully completed.
After moving to production i will gather system/dictionary stats. and in case of problem i should import thos stats .
Is that currect ? YES
Second , what about the 4 command :
SQL> EXEC DBMS_STATS.GATHER_SCHEMA_STATS ('SYS');
SQL> exec DBMS_STATS.GATHER_DATABASE_STATS (gather_sys=>TRUE);
SQL> EXEC DBMS_STATS.GATHER_DICTIONARY_STATS;
SQL> EXEC DBMS_STATS.GATHER_FIXED_OBJECTS_STATS;Should i run them all ?If you run the statistics these commands, later if you want to roll back these statistics again you need to run IMPORT statistics package command.. so that old statistics will be reloaded to database. :)