Since SAP Sybase Adaptive Server Enterprise (ASE) 12.5, ASE has provided support for backup compression. The advantage of compressing data on the fly during backup is that it can make backups use less disk space and complete in shorter amounts of time. However, backup compression does have associated costs, including more usage of CPU. In newer versions, ASE introduced new compression options that are less CPU intensive and an adjustment to the syntax.
The syntax for using the compression option is:
dump database <database_name> to<destination> compression = <0-9,100-101> load Database <database_name> from <backup_source> compression = <0-9,100-101>
|(Excluded)||Defaults to “No compression”|
|9||Highest level of compression|
|100||(Available in newer versions only) Faster compression|
|101||(Available in newer versions only) Better compression|
Using this backup compression feature will require you to experiment a bit, looking for the balance between the size of the backup file, the amount of CPU used to run the backup, and the amount of time required to complete the backup.
High compression at backup time can spike processors on platforms with a low quantity of CPUs.
An example of a dump and load performed with compression is shown below:
dump database pubs2 to "/Sybase/backups/srv2.db.pubs2.20130110.bak" with compression = 100 load database pubs2 from "/Sybase/backups/srv2.db.pubs2.20130110.bak" with compression
For ASE versions prior to 15, the compression syntax would be:
dumptran pubs2 to "compress::4::/Sybase/backups/srv2.tran.pubs2.20130110. bak" loadtran pubs2
Leave a Reply