Re: [Gusdev-gusdev] Oracle Segment Rollback in GUS

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Arnaud Kerhornou wrote:
> 
> Hi Jonathan
> 
> The installation of GUSdev went fine. I've got a question about the
> rollback segment. It is called in the GUS code, "BIGRBS0", any
> particular reason for ? What is the size of it ?
> 

Arnaud-

I created it just because I felt that the default rollback segments were
rather small; certain large operations would result in a "snapshot too old/
rollback segment too small" error and I wanted a larger rollback segment to
use in such cases.  For simplicity we decided to modify the Perl object layer 
to use it by default.  The size is arbitrary and in GUSdev it happens to be 
around 20 GB:


CREATE TABLESPACE BIGRBS DATAFILE
'/usr/local/oracle/u02/oradata/gusdev/rbs_big01.dbf' SIZE 2000M AUTOEXTEND OFF,
'/usr/local/oracle/u02/oradata/gusdev/rbs_big02.dbf' SIZE 2000M AUTOEXTEND OFF,
'/usr/local/oracle/u02/oradata/gusdev/rbs_big03.dbf' SIZE 2000M AUTOEXTEND OFF,
'/usr/local/oracle/u02/oradata/gusdev/rbs_big04.dbf' SIZE 2000M AUTOEXTEND OFF,
'/usr/local/oracle/u02/oradata/gusdev/rbs_big05.dbf' SIZE 2000M AUTOEXTEND OFF,
'/usr/local/oracle/u02/oradata/gusdev/rbs_big06.dbf' SIZE 2000M AUTOEXTEND OFF,
'/usr/local/oracle/u02/oradata/gusdev/rbs_big07.dbf' SIZE 2000M AUTOEXTEND OFF,
'/usr/local/oracle/u02/oradata/gusdev/rbs_big08.dbf' SIZE 2000M AUTOEXTEND OFF,
'/usr/local/oracle/u02/oradata/gusdev/rbs_big09.dbf' SIZE 2000M AUTOEXTEND OFF,
'/usr/local/oracle/u02/oradata/gusdev/rbs_big10.dbf' SIZE 2000M AUTOEXTEND OFF
DEFAULT STORAGE ( INITIAL 1024K NEXT 1024K MINEXTENTS 16 MAXEXTENTS UNLIMITED);

CREATE PUBLIC ROLLBACK SEGMENT BIGRBS0 TABLESPACE BIGRBS;
ALTER ROLLBACK SEGMENT "BIGRBS0" ONLINE;


Jonathan

-- 
Jonathan Crabtree
Center for Bioinformatics, University of Pennsylvania
1406 Blockley Hall, 423 Guardian Drive Philadelphia, PA 19104-6021
215-573-3115