Re: [yt-users] EnzoDatasetInMemory not working in parallel

Your tip led me to the right answer. The call to parallel_objects was happening in the derived quantity, where each processor is being made into its own comm where it is rank 0. The issue is that they then try to identify fields and incorrectly think of themselves as rank 0 for choosing which grids to look at. If I simply as ds.index right after creating the dataset, the problem goes away. This should probably just be added to the bottom of the __init__ for EnzoDatasetInMemory. Does that sound right? Britton On Mon, Jul 13, 2015 at 2:38 PM, Matthew Turk wrote:

That sounds like a new communicator got pushed to the top of the stack when it should not have been, perhaps in a rogue parallel_objects call.

On Mon, Jul 13, 2015, 8:35 AM Britton Smith wrote:

...

Hi again,

Maybe this is a clue. In _generate_random_grids, self.comm.rank is 0 for all processors, which would explain why N-1 cores are trying to get grids that don't belong to them. Interestingly, mylog.info prints out the correct rank for each of them.

Britton

On Mon, Jul 13, 2015 at 2:21 PM, Britton Smith wrote:

...

Hi Matt,

Thanks for your help. Adjust by grid._id_offset did not work, but I can that what is happening is that all processors are trying to call _read_field_names using grid 1, when only processor 0 owns that grid. I will look into why now, but if you have any intuition where to check next, that would be awesome.

Thanks, Britton

On Mon, Jul 13, 2015 at 1:51 PM, Matthew Turk wrote:

...

Hi Britton,

What looks suspicious to me is the way it's using grid.id. This might lead to an off-by-one error. Can you try it with grid.id-grid._id_offset and see if that clears it up?

...

Hi all,

I've recently been trying to use yt's inline analysis functionality with Enzo and am having some difficultly getting it to work in parallel. I am using the development tip of yt. In serial, everything works fine, but in parallel, I get the following error: http://paste.yt-project.org/show/5694/

It seems that the issue is that yt is not correctly identifying which grids are available on a given processory for the EnzoDatasetInMemory object. Does anyone have an idea of how to fix this? Has anyone else seen

On Mon, Jul 13, 2015 at 7:42 AM, Britton Smith wrote: this?

...

For reference, my user_script is just this:

import yt from yt.frontends.enzo.api import EnzoDatasetInMemory

def main(): ds = EnzoDatasetInMemory() ad = ds.all_data() print ad.quantities.total_quantity("cell_mass")

Thanks for any help,

Britton

_______________________________________________ yt-users mailing list yt-users@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org

_______________________________________________ yt-users mailing list yt-users@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org

_______________________________________________ yt-users mailing list yt-users@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org

_______________________________________________ yt-users mailing list yt-users@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org