[yt-users] EnzoDatasetInMemory not working in parallel

[Matthew Turk]

Yup, it does. Nice detective work!

On Mon, Jul 13, 2015, 8:58 AM Britton Smith <brittonsmith at gmail.com> wrote:

> 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 <matthewturk at gmail.com>
> 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 <brittonsmith at gmail.com>
>> 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 <brittonsmith at gmail.com>
>>> 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 <matthewturk at gmail.com>
>>>> 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?
>>>>>
>>>>> On Mon, Jul 13, 2015 at 7:42 AM, Britton Smith <brittonsmith at gmail.com>
>>>>> wrote:
>>>>> > 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
>>>>> 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 at lists.spacepope.org
>>>>> > http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
>>>>> >
>>>>> _______________________________________________
>>>>> yt-users mailing list
>>>>> yt-users at lists.spacepope.org
>>>>> http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
>>>>>
>>>>
>>>>
>>> _______________________________________________
>>> yt-users mailing list
>>> yt-users at lists.spacepope.org
>>> http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
>>>
>>
>> _______________________________________________
>> yt-users mailing list
>> yt-users at lists.spacepope.org
>> http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
>>
>>
> _______________________________________________
> yt-users mailing list
> yt-users at lists.spacepope.org
> http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.spacepope.org/pipermail/yt-users-spacepope.org/attachments/20150713/a39544d7/attachment.htm>