Recent EUROfusion achievements in support to computationally demanding multi-scale fusion physics simulations and integrated modelling

Integrated Modelling (IM) of present experiments and future tokamak-reactor requires numerical tools which could simulate spatially multi-scale phenomena as well as dynamically fast transient events and relatively slow plasma evolution within a reasonably fast computational time. The progress in the optimisation and speedup of the EU first-principle codes and in the development of a basis for their integration into a centrally maintained suite of IM tools achieved by the EUROfusion High Level Support Team (HLST) and Core Programming Team (CPT) is presented. Physics phenomena which can be addressed in various areas (core turbulence and magnetic reconnection, edge and SOL physics, RF heating and current drive, MHD, reflectometry simulations) following code optimisation and parallelisation performed by HLST are briefly described. The CPT development activities in support to IM including a support to local deployment of the IM infrastructure and experimental data access, to the management of releases for sophisticated IM workflows involving a large number of components and to the performance optimization of complex IM workflows are briefly summarised.