Oracle Database on ACFS: a perfect marriage?

Update: I will give this presentation at UKOUG Tech15, Wed 9 December at 14:30.

This presentation has had a very poor score in selections for conferences (no OOW, no DOAG) but people liked it very much at Paris Oracle Meetup.  The Database on ACFS is mainstream now, thanks to the new ODA releases. Having some knowledge about why and how you should run (not) Databases on ACFS is definitely worth a read.

Slides

Demo 1 recording

Demo 2 recording

Demo script (DB ACFS clone from Standby Database)

 

Comments are, as always, very appreciated 🙂

Ludo

Script that duplicates a database using a physical standby RAC as source

 It’s possibile to duplicate a database for testing purposes (it’s an example) using a standby database as source. This allows you to off-load the production environment.

This is a simple script that makes use of ASM and classic duplicate, although I guess it’s possible to use the standby DB for a duplicate from active database.
You can launch it everyday to align your test env at a point in time.

Mass datafile resizing

Recently I needed to extend many datafiles on a database with more than 500 tablespaces because a lot of tablespaces were reaching the critical threshold.
Autoextend was not an option due to a bug I encountered on 10gR2 RAC on ASM and AIX.

The solution was the following script: it generates statements to autoextend datafiles with usage over a defined threshold (the “80” in the where clause) to low down the percentage below another defined threshold (the “75” in the select clause).

Prior to extend it’s possible to show how much space is required to do this mass resizing:

10gR2 RAC hangs and “KSV master wait”

We recently migrated a customer’s 10gR2 RAC on AIX6.1 from GPFS+HACMP to a “basic” Clusterware with datafiles over ASM.
After (many) problems related to various installation bugs (the list of requirements for AIX is very long, incomplete and requires many one-off patches to complete), we had a problem during an import of a new schema: the import hung with no apparent wait events. We found that the event it was waiting for was classified as ‘Idle’:

The on ASM instance:

The problem was related to datafile resize (we use autoextend) and according to MOS, we were encountering a bug:

Bug 11712836: RESIZING DATAFILE HUNG WAITING FOR KSV MASTER WAIT IN RAC

Shutting down one instance solved the problem. Now we have to avoid autoextend……. We never encountered this bug in many 10.2.0.4 rac installations.