New issue 944: Slices of fields that need ghost zones are slow for patch AMR data https://bitbucket.org/yt_analysis/yt/issue/944/slices-of-fields-that-need-gh... Nathan Goldbaum: On my laptop, the following script: ``` #!python import yt import time def test(field): slc = yt.SlicePlot(ds, 2, field) if __name__ == "__main__": ds = yt.load("GasSloshing/sloshing_nomag2_hdf5_plt_cnt_0150") ds.periodicity = (True, True, True) setup = "from __main__ import test" t0 = time.time() test('density') tden = time.time() - t0 t0 = time.time() test('velocity_divergence') tdiv = time.time() - t0 print tden, tdiv ``` shows that it takes about 3.5 seconds to do the density slice and 63 seconds to do the velocity_divergence slice.