blk_1m hangup without any errors

[trontrytel]

A job:

OMP_NUM_THREADS=32 bicycles --outdir=outdir --case=dycoms_rf02 --nx=129 --ny=0 --nz=301 --dt=1 --spinup=3600 --nt=25200 --micro=blk_1m --outfreq=900 --backend=serial --r_c0=0.000178555555556 --rng_seed=42 --prs_tol=5e-5

hangs up without any errors.

I will run it on different nodes to see if its a hardware issue. But I get a similar hangup with rc0 =0_0.0008, so maybe it is something else