You can manually set the exact binding you desire. For example, assuming you have 8 cores, you may try – mpiexec -bind-to user:0,1+2+3+4+5+6+7 -ppn 2 -n …. to bind the first process to core 0, and the 2nd process to 1-7. Additional help is available with mpiexec -bind-to -help -- Hui Zhou From: John Cary via discuss <[email protected]> Date: Sunday, February 21, 2021 at 3:18 PM To: [email protected] <[email protected]> Cc: John Cary <[email protected]> Subject: [mpich-discuss] Does mpich have or have planned fine grained affinity control? I would like to, eg, launch 2 processes per node, with one bound to one core (used to drive a GPU), and the other to use the remaining cores for doing thread-parallel computing. Is this possible with MPICH? Thx.....John Cary _______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss