Hav you disabled firewalls on your nodes (e.g., iptables)? On Sep 25, 2012, at 11:08 AM, Richard wrote:
> sometimes the following message jumped out when I run the ring program, but > not always. > I do not know this ip address 192.168.122.1, it is not in my list of hosts. > > > [[53402,1],6][btl_tcp_endpoint.c:638:mca_btl_tcp_endpoint_complete_connect] > connect() to 192.168.122.1 failed: Connection refused (111 > > > > > > At 2012-09-25 16:53:50,Richard <codemon...@163.com> wrote: > > if I tried the ring program, the first round of pass is fine, but the second > round is blocked at some node. > here is the message printed out > > Process 0 sending 10 to 1, tag 201 (3 processes! in ring) > Process 0 sent to 1 > rank 1, message 10,start=========== > rank 1, message 10,end------------- > rank 2, message 10,start=========== > Process 0 decremented value: 9 > rank 0, message 9,start=========== > rank 0, message 9,end------------- > rank 2, message 10,end------------- > rank 1, message 9,start=========== > > I have added some printf statements in the ring_c.c as follows: > 60 printf("rank %d, message %d,start===========\n", rank, message); > 61 MPI_Send(&message, 1, MPI_INT, ! next, tag, MPI_COMM_WORLD); > 62 printf("rank %d, message %d,end-------------\n", rank, message); > > > > At 2012-09-25 16:30:01,Richard <codemon...@163.com> wrote: > Hi Jody, > thanks for your suggestion and you are right. if I use the ring example, the > same happened. > I have put a printf statement, it seems that all the three processed have > reached the line > calling "PMPI_Allreduce", any further suggestion? > > Thanks. > Richard > > > > Message: 12 > Date: Tue, 25 Sep 2012 09:43:09 +0200 > From: jody < > jody....@gmail.com > > > Subject: Re: [OMPI users] mpi job is blocked > To: Open MPI Users < > us...@open-mpi.org > > > Message-ID: > < > cakbzmgfl0txdyu82hksohrwh34cbpwbkmrkwc5dcdbt7a7w...@mail.gmail.com > > > Content-Type: text/plain; charset=ISO-8859-1 > > Hi Richard > > When a collective call hangs, this usually means that one (or more) > processes did not reach this command. > Are you sure that all processes reach the allreduce statement? > > If something like this happens to me, i insert print statements just > before the MPI-call so i can see which processes made > it to this point and which ones did not. > > Hope this helps a bit > Jody > > On Tue, Sep 25, 2012 at 8:20 AM, Richard < > codemon...@163.com > > wrote: > > I have 3 computers with the same Linux system. I have setup the mpi cluster > > based on ssh connection. > > I have tested a very simple mpi program, it works on the cluster. > > > > To make my story clear, I name the three computer as A, B and C. > > > > 1) If I run the job with 2 processes on A and B, it works. > > 2) if I run the job with 3 processes on A, B and C, it is blocked. > > 3) if I run the job with 2 processes on A and C, it works. > > 4) If I run the job with all the 3 processes on A, it works. > > > > Using gdb I found the line at which it is blocked, it is here > > > > #7 0x00002ad8a283043e in PMPI_Allreduce (sendbuf=0x7fff09c7c578, > > recvbuf=0x7fff09c7c570, count=1, datatype=0x627180, op=0x627780, > > comm=0x627380) > > at pallreduce.c:105 > > 105 err = comm->c_coll.coll_allreduce(sendbuf, recvbuf, count, > > > > It seems that there is a communication problem between some computers. But > > the above series of test cannot tell me what > > exactly it is. Can anyone help me? thanks. > > > > Richard > > > > > > > > > > _______________________________________________ > > users mailing list > > > us...@open-mpi.org > > > http://www.open-mpi.org/mailman/listinfo.cgi/users > > > > > > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users -- Jeff Squyres jsquy...@cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/