Estimating the data-size saving rate by using the hafdc2_estimator tool
The hafdc2_estimator tool can be used to sample existing data to estimate the savings rate. The hafdc2_estimator tool must be installed using the CLI on the server host that has access to the data you want to sample. For details on the hafdc2_estimator tool, contact Hitachi Solution Support Center. The following is an example of executing the hafdc2_estimator:

We recommend using the value of Saving % (Except Zero data) as the saving rate in the formula for estimating FMC capacity. The following explains the items in the execution example.
|
Items |
Description |
|---|---|
|
SAMPLE |
The number of data samples. In this example, the value is 3,000. To shorten the time required for estimation, the hafdc2_estimator tool extracts samples from the target data when executed. Therefore, the result output by the tool is an estimated value. The actual savings might vary depending on the situation. |
|
Uncompressed Bytes |
The data size before compression. The value is approximately 24 MB in the example. |
|
Compressed Bytes |
The data size after compression. The value is approximately 16 MB in the example. |
|
Saving % |
The data-size saving rate after compression. The value is 34.32% in the example. |
|
Saving % (Except Zero data) |
The data-size saving rate with all zero pages excluded from the data before compression. The value is 32.57% in the example. |
|
Compression Ratio |
The ratio of data size compression. In the example, the data size after compression is assumed to be 1, and the ratio of data size compression is 1.5. |