Questions about saving file using XDMFFile

When I run the Fenicx tutorial about the DFG benchmark examples and I try to use XDMFFile instead of using VTXWriter as follows

if mesh.comm.rank == 0:
    p_diff = np.zeros(num_steps, dtype=PETSc.ScalarType)
    xdmf = XDMFFile(mesh.comm, "FSI_Solver/view/results.xdmf", "w",encoding=XDMFFile.Encoding.ASCII)
    xdmf.write_mesh(mesh)
    xdmf.write_function(u_,t)
    xdmf.write_function(p_,t)

where “FSI_Solver” is the directory of my codes and I want to save it to the directory “view” under the parent directory “FSI_Solver”.However, after running the codes, I cannot find the view directory but the code runs well and fast.So is it wrong somewhere? Please help.Thanks in advance.
Instead, when I just use xdmf = XDMFFile(mesh.comm, "FSI_Solver/results.xdmf", "w",encoding=XDMFFile.Encoding.ASCII), it can save .xdmf file in the “FSI_Solver” directory but the time it costs is quite large.So why does it cost much time than the original way as above(but no “view” directory is found)?