  Since 2015, with the restart of the LHC for its second run of data taking,
the LHCb experiment has been empowered with a dedicated computing model to
select and analyse calibration samples to measure the performance of the
particle identification (PID) detectors and algorithms. The novel technique was
developed within the framework of the innovative trigger model of the LHCb
experiment, which relies on online event reconstruction for most of the
datasets, reserving offline reconstruction to special physics cases. The
strategy to select and process the calibration samples, which includes a
dedicated data-processing scheme combining online and offline reconstruction,
is discussed. The use of the calibration samples to measure the detector PID
performance, and the efficiency of PID requirements across a large range of
decay channels, is described. Applications of the calibration samples in
data-quality monitoring and validation procedures are also detailed.
