Hi, expert, I used freesurfer on a 32bit ubuntu operation system some days ago. For one subject, the "recon-all -s $filename -all" command need 30 hours or less. I changed it to 64bit Centos operation system, however, the precessing time needed for one subject seems longer than on 32bit system, It needs nearly 40 hours. I do not know what the matter is. Thanks!