Access to the MareNostrum 4

The access to MareNostrum is granted only based on a peer-reviewed proposal. Currently there are two methods available, which are PRACE and RES calls.

PRACE calls

PRACE offers two calls per year, i.e. one every six months. BSC provides around 120 million core hours of MareNostrum for each PRACE call. The calls are open world-wide but the technical requirements for the codes to be executed by the project are higher than for RES calls. PRACE requires that the parallel code scales up to at least 1024 or 2048 cores on MareNostrum.

PRACE also offers “preparatory access” for most of the supercomputers. These calls are meant for code scalability tests and code optimizations, including a small amount of computing time and requiring less effort for the applicant. These calls are continuously open with regular cut-off dates:

Find out more about PRACE calls:

RES calls

RES (Red Española de Supercomputación, the Spanish supercomputing network) has three calls per year, i.e. one every four months. RES provides around 34 million core hours for each call. Eligible are scientists from all over the world. It is recommended but not obligatory to have a Spanish collaborator in the applying project. To apply for computing time via RES, users need to create a new user account on and submit their proposal before the deadline of the current call. RES has no requirements with respect to the scaling behavior of the applications.

Find out more about RES calls:

Questions? Contact Javier Bartolomé (!