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<p class="MsoNormal">HI hritikesh semwal,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The error says a connection error: Connection reset by peer. Are you running 8 processes on a single node or 8 nodes?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">-- <br>
Hui Zhou<o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">hritikesh semwal via discuss <discuss@mpich.org><br>
<b>Reply-To: </b>"discuss@mpich.org" <discuss@mpich.org><br>
<b>Date: </b>Tuesday, April 28, 2020 at 8:45 PM<br>
<b>To: </b>"discuss@mpich.org" <discuss@mpich.org><br>
<b>Cc: </b>hritikesh semwal <hritikesh.semwal@gmail.com><br>
<b>Subject: </b>[mpich-discuss] Error in MPI call.<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hello all, <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Greetings of the day.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I am working on the development of a parallel CFD solver in which I am using distributed graph communicator with MPI neighbourhood collective operation MPI_Neighbor_alltoallw. While running on 2 and 4 processors, the code is working fine
but when I tried it on 8 processors it is showing following error,<o:p></o:p></p>
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<p class="MsoNormal">Fatal error in PMPI_Neighbor_alltoallw: Unknown error class, error stack:<br>
PMPI_Neighbor_alltoallw(299)..............: MPI_Neighbor_alltoallw(sendbuf=0x2fa8c20, sendcounts=0x1cd2300, sdispls=0x1cd2270, sendtypes=0x1cd2180, recvbuf=0x2fac1d0, recvcounts=0x7f167615d010, rdispls=0x7f1667ace010, recvtypes=0x7f1660786010, comm=comm=0x84000002)<br>
PMPI_Neighbor_alltoallw(285)..............:<br>
MPIR_Neighbor_alltoallw_impl(174).........:<br>
MPIR_Neighbor_alltoallw_intra_auto(93)....:<br>
MPIR_Neighbor_alltoallw_nb(33)............:<br>
MPIR_Wait_impl(77)........................:<br>
MPIDI_CH3i_Progress_wait(242).............: an error occurred while handling an event returned by MPIDI_CH3I_Sock_Wait()<br>
MPIDI_CH3I_Progress_handle_sock_event(479):<br>
MPIDI_CH3I_Socki_handle_read(4013)........: connection failure (set=0,sock=1,errno=104:Connection reset by peer)<o:p></o:p></p>
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<p class="MsoNormal">Can anyone tell me what is the solution to this problem? This would be a great help.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thank you.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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