Oracle 11gR2 Released

Oracle has released 11gR2 to some fanfare and there seems to be some major improvements especially in the way Oracle uses storage.

I thought I'd jot down some key points:

Automatic Storage Management (ASM)

11gR2 seems to be all about ASM.

It has moved into the cluster framework.

They have announce ASM Cluster File System (ACFS) which can host all files including Oracle binaries, Voting Disks, OCR, flat files etc.

You can set up disk pools in ASM of different tier disks so that when a table partition ages you can set a policy for ASM to migrate it to a different tier disk.

There are also more tuning options in ASM

There is a full featured ASMCMD

Oracle 11gR2 Data Guard.

If Oracle detects a corrupt block and the database is in a Data Guard configuration, it will check the same block on the standby. If the same block with the same SCN is not corrupted on the standby then it will automatically repair the corrupt block on the primary.

Oracle 11gR2 OLTP compression.

There is a new compression algorithm with regard to table compression. It doesn't actually compress the data in the traditional sense, instead it stores it in the block differently. It puts each distinct value into the header of the block and then records in the record a small size unique value that references it. Using this, there are dramatic improvements in reads and disk usage especially with data of low cardinality.

It was recommended that you do this for the top 10 tables in the database rather than all. Also db_block_size is a big factor in how well compression works.

Oracle 11gR2 RAC

Oracle seem to be pushing RAC as the standard. So much so that they are incorporating Oracle One Node (CRS services on a single node) as standard with the Oracle 11gR2 database allowing you to transition single node databases to another server in a RAC style graceful fail over.

They kept stressing that everything now is built and tested first for RAC.

There is also a concept of RAC server pools. You can guarantee services a particular number of nodes. If servers become available, lower priority services will make way for those with a higher priority.

New Oracle Installer

Oracle have developed a new Installer replacing the OUI which apparently is more friendly in error handling solution scripts if problems are faced during install.