HPL performance

You can improve the HPL performance by preparing an environment that is optimized for the particular load or unload job that you are performing.

You must consider the following aspects of your load and unload jobs:

The onpload configuration parameters
The onpload configuration parameters control the number of threads that onpload starts and the number and size of the buffers that are used to transfer data.
Express-mode limitations
The onstat options for onpload
The onstat utility has two options that you can use to observe the behavior of database server threads during express-mode loads.
Devices for the device array
On a data-load job, each device runs independently of other devices. Thus mixing fast and slow devices does not adversely affect the speed of the load.
HPL usage tasks
Settings for a no-conversion load or unload job
A no-conversion load or unload is not highly CPU intensive because no conversion is involved. In this case, the load or unload is expected to be limited by the speed of the tape devices. No-conversion loads and unloads are always completed in express mode.
An express-mode load with delimited ASCII
In an express-mode load with delimited ASCII, the load or unload job is limited by the available CPU. The conversion to or from HCL Informix® types to ASCII is the most expensive portion of these operations
HPL performance hints
In general, the performance of the High-Performance Loader (HPL) depends on the underlying hardware resources: CPU, memory, disks, tapes, controllers, and so on. Any of these resources could be a bottleneck, depending on the speed of the resource, the load on the resource, and the particular nature of the load or unload.

Parent topic: Manage the High-Performance Loader

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