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Hello FreeSurfer Developers,

I'm recently attempting to run Freesurfer for structural MRI on VM on Google Clound Platform with the hope that recon-all runtime can be shortened in a great deal. My own Desktop is Mac Pro (3.7 GHz quad-core intel xeon E5, 16G memory). The recon-all runtime (Freesurfer version 5.3.0, no parallel) for a single subject is usually 7~8 hours. The specs of VM on GCP as follows, Linux CentOS 6, 16 CPU(Intel(R) Xeon(R) @ 2.50GHz) with 60 G memory I installed Freesurfer v 6.0.0 and run recon-all with -parallel -openmp num flag No matter what number I put (6,8,12,16 after openmp), the recon-all runtime of single subject ranges 6-7 hours. Is this reasonable? So only 1-2 hour shorter than my Mac Pro?? Or is there anything I should pay attention to set up?

Thanks~~