Great! Let me know if I need to do anything.
Thanks,
Matt
On Mon, Jan 19, 2026 at 2:16 PM MIGUEL MOLINOS PEREZ <[email protected]> wrote:
> Understood!
>
> I think I can make it work because the way I create ghost particles in my
> code is with:
> (i)DMSwarmAddNPoints,
> (ii) two auxiliar variables named idx_ghost and rank_ghost,
> (iii) and DMSWARM_MIGRATE_BASIC for the migration.
>
> In summary, shared particles are indeed at the end of the Vec.
>
> Actually you helped me with this hack months ago :-).
>
> I think I can use the code you mentioned as an inspiration… let's see!
>
> Miguel
>
> On Jan 19, 2026, at 7:26 PM, Matthew Knepley <[email protected]> wrote:
>
> The code is the right place to look. For example
>
>
> https://urldefense.us/v3/__https://gitlab.com/petsc/petsc/-/blob/main/src/dm/impls/swarm/swarm.c?ref_type=heads*L307__;Iw!!G_uCfscf7eWS!eE960jNqKVw0srPisAtE4Y8NlgL2aPXto1rNFpISsZTuFMb2PEIeR2IZFPLH_Jg0MfO8sFXiX8OhusFg-MMo$
>
>
> So the Vec will get the right type. This means that when the initial data
> comes in on the host, it will be copied to the device when we execute an
> operation.
>
> We (really Joe) are working on an update that allows swarm data to be held
> on the device.
>
> Thanks,
>
> Matt
>
> On Mon, Jan 19, 2026 at 1:22 PM MIGUEL MOLINOS PEREZ <[email protected]>
> wrote:
>
>> I’ll check the documentation more carefully to see if I can find this.
>>
>> Thanks,
>> Miguel
>>
>> On Jan 19, 2026, at 6:42 PM, Matthew Knepley <[email protected]> wrote:
>>
>> On Mon, Jan 19, 2026 at 12:19 PM MIGUEL MOLINOS PEREZ <[email protected]>
>> wrote:
>>
>>> I don’t think so because DMSwarm data is allocated on host. This is
>>> right Matt?
>>>
>>
>> I believe there is code in there to move it if you give a device type.
>>
>> Thanks,
>>
>> Matt
>>
>>
>>> Thanks,
>>> Miguel
>>>
>>> On Jan 19, 2026, at 5:44 PM, Junchao Zhang <[email protected]>
>>> wrote:
>>>
>>> With VecCreateGhostWithArray, do you already have the array ready on
>>> device?
>>>
>>> --Junchao Zhang
>>>
>>>
>>> On Mon, Jan 19, 2026 at 6:56 AM MIGUEL MOLINOS PEREZ <[email protected]>
>>> wrote:
>>>
>>>> Dear all,
>>>>
>>>> I have a question about using DMSwarm data with Kokkos-enabled vectors.
>>>>
>>>> My particle data (including ghost particles) are stored in a DMSwarm
>>>> and for solver purposes I generate PETSc vectors using
>>>> VecCreateGhostWithArray. I would like to use VecMPIKOKKOS for MPI+GPU
>>>> computations. Am I correct that DMSwarm field memory cannot be directly
>>>> wrapped into a VecMPIKOKKOS using VecCreateGhostWithArray or VecPlaceArray?
>>>> Any idea on how to proceed?
>>>>
>>>> Thanks in advance.
>>>>
>>>> Best,
>>>>
>>>> Miguel
>>>>
>>>
>>>
>>
>> --
>> What most experimenters take for granted before they begin their
>> experiments is infinitely more interesting than any results to which their
>> experiments lead.
>> -- Norbert Wiener
>>
>> https://urldefense.us/v3/__https://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!eE960jNqKVw0srPisAtE4Y8NlgL2aPXto1rNFpISsZTuFMb2PEIeR2IZFPLH_Jg0MfO8sFXiX8Ohusvaptrj$
>>
>> <https://urldefense.us/v3/__http://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!eE960jNqKVw0srPisAtE4Y8NlgL2aPXto1rNFpISsZTuFMb2PEIeR2IZFPLH_Jg0MfO8sFXiX8OhuimerKcC$
>> >
>>
>>
>>
>
> --
> What most experimenters take for granted before they begin their
> experiments is infinitely more interesting than any results to which their
> experiments lead.
> -- Norbert Wiener
>
> https://urldefense.us/v3/__https://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!eE960jNqKVw0srPisAtE4Y8NlgL2aPXto1rNFpISsZTuFMb2PEIeR2IZFPLH_Jg0MfO8sFXiX8Ohusvaptrj$
>
> <https://urldefense.us/v3/__http://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!eE960jNqKVw0srPisAtE4Y8NlgL2aPXto1rNFpISsZTuFMb2PEIeR2IZFPLH_Jg0MfO8sFXiX8OhuimerKcC$
> >
>
>
>
--
What most experimenters take for granted before they begin their
experiments is infinitely more interesting than any results to which their
experiments lead.
-- Norbert Wiener
https://urldefense.us/v3/__https://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!eE960jNqKVw0srPisAtE4Y8NlgL2aPXto1rNFpISsZTuFMb2PEIeR2IZFPLH_Jg0MfO8sFXiX8Ohusvaptrj$
<https://urldefense.us/v3/__http://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!eE960jNqKVw0srPisAtE4Y8NlgL2aPXto1rNFpISsZTuFMb2PEIeR2IZFPLH_Jg0MfO8sFXiX8OhuimerKcC$
>
