3rd. day at the Oracle Open World

Last night was the customer appreciation event with Billy Joel, Lenny Kravitz and Stevie (Fleetwood mac). I got to my hotel pretty late and was exhausted, so I am trying to catch up today.

My first session of the day was "Oracle 11g simplifying management of Oracle database files by Aiman Al-Khammash". This session was mostly about ASM and how you can leverage it to help you administer your database files. ASM (Automatic Storage Manager) provides better performance than OCFS (Oracle Cluster File system).

11g allows rolling upgrades patches for Clusterware and ASM, in 11g you can have variable size extends and the extend size grows automatically with the file. 11g also increases maximum ASM size which is platform dependent. In 11g the allocation unit (AU) is not longer 1MB. as in 10g, you can now set it up to 1, 2, 4,8,16,32,64 MB. Same as in 10g the striping size is one allocation unit (AU) an file stripe is 128KB.

There are new ASM disk group attributes such as

AU_SIZE , DISK_REPAIR_TIME (Length of time before removing a disk once offline), COMPATIBLE_ASM and COMPATIBLE_RDBMS.

There is also a new view: V$ASM_ATTRIBUTE

There are new command line parameters (asmcmd):

lsdsk = List asm disks.
cp = Copy files between asm and non asm storage
remap = Re-maps unreadable blocks in normal high redundancy
md_backup / md_restore = Backup and restore ASM disk group environment.

In addition you can use $asmcmd help to find commands

My second session was "Backup and recovery best practices for very large databases by Tim Chien". Tim explained that every day disk is becoming a more popular backup media since you get performance at a low cost. Tim spoke about VTL (Virtual Tape Libraries) and said they provide you the best of both worlds (tape / disk). He advised to allocate disk backup for the most critical databases, and he also suggested to use locally attached tape drives. Tim suggest the to use the following tools:

- RMAN (Incremental backups)
- Data Pump
- Oracle Secure Backup
- Flash back technology (This is redo base).
- Data Guard (Use it as a disk backup or take the backup out of it)

Use third party storage space solutions.

- Snapshots
- Split mirror backup
- CDP appliances (provides continue snapshot copy-on-write or
allocate-on-write)

Plan your data layer and exploit partitioning and read only tablespaces.

Develop your backup procedure using the following options

Option 1: Use level 0 (FULL) and fast incremental backups.

Option 2: Use level 0, fast incremental backups and incremental updates backup.

Option 3: Data Guard + Full incremental backups.

Option 4: Maintain ETL loads , restore full backups and run needed ETL.

Consider the use of nologging (used widely for Data warehouses to speedup performance.

Divide full backup workloads across multiple days.

New in 11g he said you can use multi section backups (intra file parallel backup)

And lastly develop recovery strategies and use the data recovery advisory.


Then I assisted to "Larry Ellison key notes" Larry was introduced by Billy Joel and then he announced once again Oracle Virtualization and the software was open for download after the announcement. Larry basically spoke about what they heard the customers wants and what Oracle is doing to cover that demand. He also made reference to Unbreakable and the fact that despite it has been only one year since they launched it and they have not sales force for it several big companies have moved to it.

My fourth meeting of the day was "Oracle Active data guard and how to utilize your standby databases for production workload by Grant McAlister" . Grant started by explaining the traditional physical standby architecture

He also spoke about "Active data guard" which is a new Oracle option for which you have to pay a license fee; basically it allows you to continue ship and apply of redo on the standby while the database is in read only mode, with this you get better utilization and performance.

Grant said that you can scale out with active data guard as you can have your reports been feed out of the read only standby.

Active Data Guard allows real time query and RMAN block change tracking on a standby database. When the DB is open read only the consistency is guarantee since it is maintained through query scn.

Whole the database is open read only you can select and alter session. He also spoke about the best practices such as what are the apps that are candidate for active data guard. Grant explained how he was able to scale out just separating the queries from the writes.

He mentioned 3 methods to redirect writes:

1. - DML application level change.
2. - Use of a Database Link
3. - DML via database link.

He advises to use synonyms to hide the database links, keep in mind that from a read only database you can't invoke a remote store procedure.

My last session was "Oracle Data Guard tips and tricks by Larry Carpenter".
Larry started encouraging people to use ASM, he said it provides ease of management and advises the following:

- Use ASM
- Use Flashback recovery area
- Use RMAN to create your standby database.

Convert your standby first to ASM in that way moving to ASM does not mean downtime. He explained how having a flash recovery are simplifies management. The flash recovery area is required for flash back database. Larry explained how to turn on the flash recovery option. He explained that running jobs in the logical standby will not work until the standby gets to be the primary. In 11g you can use the DBMS_SCHEDULER on the active , the standby or both.

Well that is all for today folks.