If you advance disk group compatibility, then you could enable the creation of files that are too large to be managed by a previous release of Oracle Database. You must be aware of the file size limits because replicated sites cannot continue using the software from a previous release to manage these large files. The disk group compatibility settings should be the same for all replicated environments.
Table 4-5 shows the maximum Oracle ASM file sizes supported for COMPATIBLE.RDBMS settings when the AU_SIZE attribute is set to one megabyte for a disk group.
Table 4-5 Maximum Oracle ASM file sizes for disk groups with AU_SIZE equal to 1 MB
| Redundancy | COMPATIBLE.RDBMS = 10.1 | COMPATIBLE.RDBMS >= 11.1 |
|---|---|---|
|
External |
16 TB |
140 PB |
|
Normal |
5.8 TB |
23 PB |
|
High |
3.9 TB |
15 PB |
Table 4-5 shows that Oracle Database 10g can only support a file size of up to 16 TB for external redundancy. If you advance the COMPATIBILE.RDBMS attribute to 11.1 or greater, then a file can grow beyond 16 TB. However, the larger size causes the file to be unusable in a replicated and disaster recovery site if the disaster recovery site has a disk group COMPATIBLE.RDBMS setting that is incompatible with the larger size.
For information about Oracle ASM storage sizes, see "Oracle ASM Storage Limits".
Oracle Database Upgrade Guide for information about database compatibility
Oracle Database Administrator's Guide for information about the COMPATIBLE initialization parameter and irreversible compatibility
Oracle Database Reference for information about the COMPATIBLE initialization parameter