I’ve been testing the new EMC Unity 600F all-flash storage array with an Oracle database to determine the impact of storage compression on Oracle I/O performance. To do this I have been using Kevin Closson’s SLOB tool.
SLOB is an excellent tool for testing I/O performance as seen by Oracle. Unlike Swingbench which mimics a real application and therefore spends much of its execution cycle on the server CPU, SLOB concentrates exclusively on generating I/O from the Oracle stack.
Conversely, don’t expect SLOB to generate meaningful data to test ranking or sorting operations inside of Oracle. SLOB generates entirely synthetic data that is meaningless from an application standpoint.
The following posts covers using SLOB to test I/O performance, and what was learned from the testing against the Unity 600F all-flash array.
Increasingly the old paradigm of nightly backing up your large Oracle database to tape, or writing the backup to a NAS share which is then mysteriously swept to tape by some unseen force (the Sys Admins), is becoming an unsustainable approach when backup windows are shrinking, 24/7 availability is becoming the norm and databases are getting larger and larger.
Backup Appliances, such as Sun’s ZDLRA or EMC’s Data Domain, offer many performance and manageability advantages over traditional approaches, and much of the work of traditional backup software is now baked into the appliance itself.
A modern database backup and recovery appliance should include features such as data encryption, compression, de-duplication and remote replication as standard features, to offload those functions from the host CPUs which we want to dedicate to running the database software.
EMC’s Data Domain includes SISL technology – Stream-Informed Segment Layout – to yield some very impressive data reduction numbers using a combination of de-duplication and compression.
But what happens if we choose to use RMAN features in addition to those offered by the backup applicance? What happens if we try to encrypt, de-duplicate, or compress, an RMAN backupset that is itself encrypted or compressed?