2.1.4 Snapshot-Aware XRMEM Cache

Oracle Exadata System Software release 26.1.0 enhances XRMEM cache by making it fully Exascale snapshot-aware. With these enhancements, XRMEM cache stores only data blocks that are unique to a snapshot and avoids caching blocks that are unchanged from the snapshot source.

By removing snapshot-related duplication in the cache, this enhancement effectively increases cache capacity, reduces read latency, improves RDMA hit rates, reduces disk I/O, and improves throughput for more users system-wide.

This capability is especially useful in Exascale environments with many snapshots or clones, where duplicate caching can otherwise consume valuable XRMEM cache capacity.