We have reduced the per-user-resource limits for main memory on the HPC dialog systems (login18-1.hpc.itc.rwth-aachen.de etc.). A single user can now only use about 25% of the available main memory, i.e. 96GB for most of our servers. On login18-x-1 and login18-x-2, as before, only 16 GB are available to each user.