Exadata

The Exadata tab provides a unified view of Oracle Exadata hard disk and flash performance statistics.

It gives a deep insight into the health and performance of system components including the databases, Exadata storage cells, and Automatic Storage Management (ASM). You can use the Exadata tab for enhanced performance diagnostics for Exadata databases.

This tab is available for Exadata Databases managed through External Database and databases in Exadata Database Service on Dedicated Infrastructure deployments.

Note

The Exadata tab is available only in the historical mode and supports only container databases. It does not provide real-time views, or any information about pluggable databases.

In the Exadata tab, you can:

  • Analyze outliers that affect database performance, including finding a slow disk component that is affecting the system

  • Analyze performance characteristics of multiple databases deployed in an Exadata system

  • Identify a high I/O load and classify the load as Backup, Rebalance, User I/O, and others

  • Identify CPU bound cells and determine cell offload

  • Identify configurations such as versions and disk status

It provides various statistics about databases running on Exadata systems, including:

  • Operating system statistics

  • Storage server software statistics

  • Smart scan statistics

  • Database, disk, and cell statistics

  • Exadata-specific ADDM recommendations

  • Exadata system statistics

Exadata Details

The Exadata Details page contains nine tabs:
  • Performance - shows database performance, including a summary, latency statistics, flash I/O statistics, and Hard Disk I/O statistics

  • Health - shows the number and type of open alerts (Information, Warning, and Critical), the number of offline disks, open alert details, and offline disk details

  • ADDM - displays Automatic Database Diagnostic Monitor (ADDM) performance findings specific to Exadata for the selected ADDM task, and makes specific recommendations to correct performance problems.

  • Top Consumers - identifies workload distribution across all databases including the databases that consume a significant amount of I/O bandwidth. I/O requests and I/O throughput aggregates the data to report the top databases captured. The tab shows the number of requests, I/O speed, and usage of the top databases per cell in the Exadata system. It also displays details of IORM Queue Time and the top databases per cell.

  • Cells and Disks - compares the operational statistics of the flash drives and hard disks in the system.

    It provides I/O related information, such as:
    • how I/O is distributed between flash drives and hard disks

    • realize the benefit the system is getting from Flash Cache

    • how much disk I/O is caused by Flash Cache

    • how I/O correlates to database single block reads

    The tab displays statistics by cell, including the Top Cells, Outlier Cells, OS I/O Throughput, Cell Server I/O Requests, Cell Server I/O Throughput, % Disk Utilization, I/O Latency, and Cell Latency. You can select the default column group by which to display the data. Hover the cursor over a statistic to view details about it.

  • Smart I/O - displays summaries and details of Flash log and Flash Cache statistics by cell.

  • I/O Reasons - displays the number of requests and bytes for the set of selected cells to show the reasons for a high I/O load by category. Categories include backup, rebalance, and user I/O. The Requests and Bytes statistics bars for each cell are broken into sections that show the number of database control file reads per second, voting files I/O operations per second, and xrov I/O operations per second, and others.

  • Configuration - displays the configuration of the storage server model, the storage server version, and the objective of each cell.

For more information, see: