Twisted mass gauge ensembles at physical values of the light, strange and charm quark masses

Lattice QCD simulations directly at physical masses of dynamical light, strange and charm quarks are highly desirable especially to remove systematic errors due to chiral extrapolations. However such simulations are still challenging. We discuss the adaption of efficient algorithms, like multi-grid methods or higher order integrators, within the molecular dynamic steps of the Hybrid Monte Carlo algorithm, that are enabling simulations of a new set of gauge ensembles by the Extended Twisted Mass collaboration (ETMC). We present the status of the on-going ETMC simulation effort that aims to enabling studies of finite size and discretization effects. We work within the twisted mass discretization which is free of odd-discretization effects at maximal twist and present our tuning procedure.