| Feature | DB2 | VSAM |
| Performance Tuning | Can be tuned anytime Writes SMF records Can be at SQL level Tools available for aiding Subsystem level tuning possible Abundant tuning skills | Depends on initial design No SMF records Only application level No tuning aids Not a subsystem Tuning skills are rare | |
| CPU & IO parallelism | Scanning is Faster | No parallelism | |
| Parallel Sysplex | Can participate Optimizer handles | Can participate No optimization | |
| Reorganization | Direct reorganization Online reorg possible Parallel reorg | Delete & recreate Downtime needed No parallelism | |
| Recovery | Managed by DB2 Always recoverable From log / backup Auto Recovery Parallel recovery | Managed by CICS/IMS No recovery in batch From backup only Manual Restore No parallelism | |
| Backup | Online backup possible Incremental backup Parallel backup | Downtime needed No incremental backup No parallelism | |
| Availability | Parallel reorg, backup Online reorg, backup Less downtime | No online maintenance No parallelism More Downtime | |
| Disaster Recovery | Supported by DB2 | Part of DASD recovery |
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