Smart-Scan

AWR reports are simultaneously the most powerful and most misread performance tool in Oracle’s arsenal. Most DBAs jump straight to Top SQL, copy the SQL_ID, and start tuning — skipping the sections that tell them why that SQL became a problem in the first place. This case study walks through a realistic AWR from a production Exadata system, section by section, using a deliberately constructed problematic scenario. Every number is fabricated for illustrative purposes; every diagnostic conclusion is grounded in real Oracle internals. ...

When multiple VM Clusters share the same Exadata storage cells on ExaCC, storage I/O becomes a shared resource that can interfere between workloads. Oracle’s I/O Resource Manager (IORM) is the mechanism for controlling how storage I/O is distributed across VM Clusters, databases, and consumer groups. Without IORM configuration, a single runaway workload on one VM Cluster can starve others. IORM Architecture on ExaCC IORM operates at two levels: Inter-VM Cluster IORM (configured via OCI): Controls storage I/O allocation between VM Clusters sharing the same physical Exadata infrastructure. Intra-database IORM (configured via DBCA or DBRM): Controls I/O between databases within a single VM Cluster and between consumer groups within a database. Because ExaCC does not give customers cellcli access, inter-VM Cluster IORM is configured through the OCI Console or API — Oracle’s management layer pushes the configuration to the storage cells. ...

If you are running workloads on Oracle Exadata, you are likely sitting on a goldmine of performance capability. The most significant differentiator between Exadata and traditional storage architectures is a feature called Smart Scan (also known as Cell Offload Processing). Instead of treating storage as dumb disks that just serve blocks to the database, Exadata pushes SQL processing down to the storage tier. This article explains how Smart Scan works, how to verify it, and how to control its behaviour for testing. ...

The Exadata X11M platform separates database compute and storage cells connected via an RDMA-capable RoCE fabric. This page summarizes hardware variants and provides practical command-line examples for common administration, troubleshooting and monitoring tasks. Architecture Overview Database Servers (Compute) These servers run the database and client-facing workloads. Standard Exadata X11M Database Server CPU: 2x 96-core AMD EPYC 9J25 (192 physical cores) Memory: 6400 MT/s DDR5, 512 GB–3 TB Local storage: 2x 3.84 TB NVMe (OS / Oracle binaries) Exadata X11M-Z Database Server (Entry) ...