@@ -904,6 +906,33 @@ However, it supports the following additional REST API actions:
| means | Returns the means of the generated gaussian components in the trained mixture model.
| covs | Returns the covariance matrices of the generated gaussian components in the trained mixture model.
## CS Signatures Plugin <a name="csPlugin"></a>
The _CS Signatures_ plugin computes signatures from sensor data as described in the paper _"Correlation-wise Smoothing: Lightweight Knowledge Extraction for HPC Monitoring Data"_ by Netti et al. The signatures aggregate data both in time and across sensors, and are composed by a specified number of complex-valued _blocks_.
Each of the blocks is then stored in two separate sensors, which contain respectively the real and imaginary part of the block. Like in the _Regressor_ and _Classifier_ plugins, the CS algorithm is trained using a specified number of samples, which are accumulated in memory, subsequently learning the correlations between sensors.
Operators in this plugin support the following configuration parameters:
| Value | Explanation |
|:----- |:----------- |
| window | Length in milliseconds of the time window that is used to retrieve recent readings for the input sensors, starting from the latest one, that are then aggregated in the signatures.
| trainingSamples | Number of samples for the sensors that are to be used to train the CS algorithm.
| numBlocks | Desired number of blocks in the signatures.
| inputPath | Path of a file in which the order of the sensors and their upper/lower bounds are stored.
| outputPath | Path of a file to which the order of the sensors and their upper/lower bounds must be saved.
Additionally, the output sensors of the CS Signatures plugin support the following parameters:
| Value | Explanation |
|:----- |:----------- |
| imag | Boolean value. Specifies whether the sensor should store the imaginary or real part of a block.
The output sensors are automatically duplicated according to the specified number of blocks, and a numerical identifier is appended to their MQTT topics. If no sensor with the _imag_ parameter set to true is specified, the signatures will contain only their real parts.
Finally, the plugin supports the following REST API actions:
| Action | Explanation |
|:----- |:----------- |
| train | Triggers a new training phase for the CS algorithm. For practical reasons, only the sensor data from the first unit of the operator is used for training.
## Tester Plugin <a name="testerPlugin"></a>
The _Tester_ plugin can be used to test the functionality and performance of the query engine, as well as of the Unit System. It will perform a specified number of queries over the set of input sensors for each unit, and then output as a sensor the total number of retrieved readings. The following are the configuration parameters for operators in the _Tester_ plugin: