The dataset presents, the estimation of the Multi-ejector performance in a supermarket, based on the compressor mass flow rates from a trained data-driven method, (refer to https://doi.org/10.18710/HS8QAH) and the comparison with the existing performance function based on operational conditions. The pilot installation used the dataset is in the frame of MultiPack, an EU funded project. The Multipack is an integrated R744 parallel compression system with expansion work recovery through Multi Ejector SolutionTM, providing: refrigeration, space heating and cooling, and hot water production as shown in Figure 1. The space cooling and heating are by two direct CO2 rooftop air handling units. Three compression groups were installed in the pilot. Three compressors for medium temperature level (MT comp), three compressors at Low-Temperature level (LT comp), and four units are dedicated for Air-Conditioning (AC comp) total installed electrical power for compressors and fans is 177 kW (Excluding air handling fans). A paper, based on this dataset, "Performance of integrated R744-packs Part 2 - Ejectors performance, a comparison of onsite measurements and model predictions" was published at a conference (Compressors Conferences).