Where is the amount of data known from?

The amount of data is known from several sources and methods:

• Metadata and logs: data storage and processing systems usually keep track of the volume of uploaded or processed data.
• Monitoring tools: for example, analytics systems (Google Analytics, Prometheus) show the volume of collected data.
• Preliminary analysis: when uploading datasets, their size, number of records, and volume in bytes can be obtained.
• Data engineering: data processing pipelines often include stages of counting and validating data volume.

Thus, the amount of data is known thanks to accounting, monitoring, and metadata analysis systems, which is important for assessing the quality and volume of training samples in machine learning.