Oracle Database 11g shoots the moon
Oracle's enormous 11g release rumbles with an impressive array of performance and management aids, elegant application testing, standbys that earn their keep, and the promise of lower storage requirementsFollow @infoworld
Another way to go about analyzing your workload, complete with graphs, is to simply record the data in SQL Performance Analyzer as you run your replay workloads. The database doesn't know the difference between a workload being fed by 100 users or by a generator hitting it with 100 virtual users, so you can simply capture the live data in Performance Analyzer while you're doing your replay tests.
The easiest way to get bang for your Real Application Testing buck is to use Database Replay in conjunction with Data Guard's Snapshot Standby feature, discussed above, which saves the state of your standby database and allows you to restore it later (along with logs that have been shipped in the meantime). The combination of Database Replay and Snapshot Standby gives you a powerful and flexible way to test changes to your applications. You simply capture the workload on the primary using Database Replay, set your standby in read/write mode, make the changes you need to make, and then replay the workload on the standby. When you've finished testing, you can record your results and put the standby back into a consistent state with the primary.
Figuring out how to accurately test changes in your own real-world environment without doing it in production is one of the biggest problems in database management. Database Replay solves this problem in an easy and elegant way.
Another separately licensed option is Advanced Compression. A way of writing data to disk so that it takes up less space, Advanced Compression can reduce storage costs, reduce memory and network bandwidth requirements, and even improve query performance.
Advanced Compression saves storage space by replacing duplicate values (like the date in orders placed throughout a given day) in a data block with symbols for those values. In other words, Advanced Compression doesn't actually compress the values, but normalizes the data just like database design does. The more repetitive your data is, the more success you're going to have with Advanced Compression. Also, because Advanced Compression works at the block level, the compression ratio will depend on how you order the data in your tables.
In addition to storing more data on disk, Advanced Compression can improve I/O performance. Because more data is being squeezed into less space, it's easier for the database to satisfy queries. The database is physically pulling less data from disk for the same information, so it can do it faster. The catch is that these benefits only extend to table scans, not indexed queries.
So Advanced Compression will improve the performance of some queries, but not others. And it will dramatically reduce storage requirements for some kinds of data, but not others. Further, even for the same kinds of data, overall compression ratios will differ depending on how often the data repeats and how you order (index) the data.
Finally, percent free (PCTFREE), the percentage of a page left empty for inserts or updates, will also be a factor. The better the data "compresses," the more of it will fit on a page, and the fewer pages the engine must traverse to satisfy the query. These gains could be seen everywhere from slightly faster queries to reduced blocking.
I tested Advanced Compression against two separate databases. In the first case, the database was generated from the TPC-C order entry benchmark, which simulates a complete environment for online transaction processing. In the second case, the database was the OLTP Table Compression Test Kit provided by Oracle.