Hi @all, creating connections via create_qp fails on our cluster for rather small numbers of processes (128 is working, 256 not) due to an out-of-memory error. I've tracked down the issue to an mlx5_alloc_buf call, which allocates ~500kB per call, which seems to be a lot. heaptrack tells me the following: 34.47M peak memory consumed over 92 calls from mlx5_alloc_buf in /usr/lib64/libibverbs/libmlx5-rdmav34.so 8.65M consumed over 16 calls from: create_qp in /usr/lib64/libibverbs/libmlx5-rdmav34.so mlx5_create_qp in /usr/lib64/libibverbs/libmlx5-rdmav34.so . Can anyone help me to understand, what causes a 500kB allocation in create_qp? Maybe it is some sort of a configuration issue, which I can handle somehow. Thanks for help and best regards Olaf Krzikalla System information: CentOS Linux 7 (Core) Linux 3.10.0-1160.88.1.el7.x86_64 CA 'mlx5_0' CA type: MT4123 Number of ports: 1 Firmware version: 20.33.1048 Hardware version: 0
