Re: Oracle Parallel Server Question

There is a GC_ROLLBACK_LOCKS parameter
(or something close to it, better look it up, can't remember it off the top of my head) that is used for assigning PCM locks to rollback segments.

Temp tablespace datafiles should not have a reference in GC_FILES_TO_LOCKS. Also consider isolating your temp tablespaces to users on seperate servers to increase performance. That way there will be no x-instance communication regarding the access to the temporary space. For example

Server 1 temp_server1
Server 2 temp_server2
Server 3 temp_server3

alter user UseServer1 temporary tablespace temp_server1 alter user UseServer2 temporary tablespace temp_server2

and so on. I have found that it increases my query performance.

Hope this helps.

Esme Venter wrote in message <6q6jqt$h13$1_at_hermes.is.co.za>...
>Hi
>We run OPS on twelve nodes for our Datawarehouse. Data in a few large
>tables get updated twice monthly.
>All related indexes are dropped prior to inserts/updates and recreated
>afterwards.
>I need some help to make sure that I have set my GC_FILES_TO_LOCKS
parameter
>correctly.
>
>Currently I have set it as follows :
>
>For SYSTEM datafile : 500
>For ROLLBACK datafiles : 500 ( 12 datafiles which is one datafile
>containing private rolback segments for EACH of the twelve nodes.)
>For TEMPTS1 : 100 (10 datafiles)
>For TEMPTS2 : 100 (10 datafiles)
>
>GC_DB_LOCKS = 4001 (So all the other datafiles share the remaining 2801
>locks.)
>
>Firstly, The OPS manual suggests that no PCM locks should be assigned to
>files which only hold ROLLBACK SEGMENTS or TEMPORARY data.
>
>Question: Does this mean I have to omit the datafiles belonging to
ROLLBACK
>and TEMP tablespaces from the GC_FILES_TO_LOCKS parameter or should I
>include them with a value of 0?
>
>Thanks in advance.
>
>
>
Received on Thu Aug 06 1998 - 22:19:19 CDT