The readiness of the ATLAS Trigger-DAQ system for the second LHC run

After its first shutdown, the Large Hadron Collider (LHC) will provide proton-proton collisions with increased luminosity and energy. In the ATLAS experiment~\cite{Atlas}, the Trigger and Data Acquisition (TDAQ) system has been upgraded to deal with the increased event rates~\cite{TDAQPhase1}. The updated system is radically different from the previous implementation, both in terms of architecture and expected performance. The main architecture has been reshaped in order to profit from the technological progress and to maximize the flexibility and efficiency of the data selection process. Design choices and the strategies employed to minimize the data-collection and the selection latency will be discussed. First results of tests done during the commissioning phase and the operational performance after the first months of data taking will be presented.