Performance of LHCb Upgrade I in Run 3

LHCb is a general-purpose forward detector at the LHC which is particularly suited to precision measurements in the beauty and charm sectors. During the LHC Long Shutdown 2 the experiment went through a massive upgrade, namely Upgrade I, to cope with the increase of the instantaneous luminosity $\mathcal{L}=2\times10^{33}$cm$^{−2}$ s$^{-1}$ in Run 3. A fully software based trigger was implemented and most of the subdetectors were upgraded. The upgraded tracking system, together with the particle identification subdetectors, will be presented. Early 2022 data has been used to perform a full validation of the detector, improving alignment and calibration. First Run 3 performance extracted will be shown.