Progress
Database Administration
Guide and Reference
Optimizing Data For Random Access
If your application accesses data in a random order, for example an online transaction-processing application, you can dump and reload the data to optimize it for random access. Use a database with small, fixed-length extents spread across the volumes to balance the I/O across the disks. Use several clients to load data simultaneously, thereby spreading the data across all disks.
This technique also improves load performance on SMP platforms.
Follow these steps:
- Dump the data and definitions.
- Load the definitions using the Data Dictionary or the Data Administration tool.
- In multi-user mode, start a server with a before-image writer (BIW) and asynchronous page writer (APW).
- Start a client for each processor on your system. Have each client load certain tables. For each client, write a Progress 4GL procedure similar to the following:
The clients, loading the data simultaneously, distribute the data across all disks. This eliminates hot spots (that is, areas where data might be concentrated).
- After the data is loaded, perform a full index rebuild. Use the PROUTIL IDXBUILD utility.
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