<div>gmx-ers:</div>
<div> </div>
<div>A while ago Beniamino posted a question regarding the difficulty in doing constraint force in parallel. I am having the same problem now. Specifically, when attemping to run on several nodes using mpirun, the code says:</div>
<div> </div>
<div>Fatal error: <br>Can not do constraint force calculation in parallel!<br><br>Is this a problem with the way I am using gromacs or it is a known limitation (unlikely, I feel).</div>
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<div>Nick<br></div>
<div class="gmail_quote">---------- Forwarded message ----------<br>From: <b class="gmail_sendername">Nickle Fan</b> <<a href="mailto:nicklefan@gmail.com">nicklefan@gmail.com</a>><br>Date: Wed, Feb 27, 2008 at 9:36 PM<br>
Subject: inquiry on constraint force run<br>To: <a href="mailto:superbenji83@gmail.com">superbenji83@gmail.com</a><br><br><br>
<p>Hi, Beniamino:</p>
<p>I am attemping to do some constraint force calculation myself, but had similar problems you mentioned earlier, i.e., mdrun shot back an error saying "Can not do constraint force calculation in parallel!".</p>
<p>Did you resolved this issue at that time. I am not sending it to the Gromacs list in case this has already been resolved.</p>
<p>Thanks.</p>
<p>Nick</p>
<p>On Sun, Jun 4, 2006 at 2:12 PM, Beniamino Sciacca <<a href="mailto:superbenji83@gmail.com" target="_blank">superbenji83@gmail.com</a>> wrote:<br>> <br>> <br>> 2006/6/4, Beniamino Sciacca <<a href="mailto:superbenji83@gmail.com" target="_blank">superbenji83@gmail.com</a>>:<br>
> > <br>> > Ops... I've another new problem, that there wasn't before....<br>> > <br>> > ---------------------------------------------------------------<br>> > <br>> > <br>> > Program mdrun_d, VERSION 3.3.1<br>
> > <br>> > Source code file: pullinit.c, line: 244<br>> > <br>> > Fatal error: <br>> > Can not do constraint force calculation in parallel!<br>> > <br>> > -------------------------------------------------------<br>
> > <br>> > "Exactly" (Pulp Fiction)<br>> > <br>> > Error on node 0, will try to stop all the nodes<br>> > Halting parallel program mdrun_d on CPU 0 out of 2 <br>> > <br>> > gcq#96: "Exactly" (Pulp Fiction)<br>
> > <br>> ><br>> -----------------------------------------------------------------------------<br>> > One of the processes started by mpirun has exited with a nonzero exit<br>> > code. This typically indicates that the process finished in error. <br>
> > If your process did not finish in error, be sure to include a "return<br>> > 0" or "exit(0)" in your C code before exiting the application.<br>> > <br>> > PID 7593 failed on node n0 ( <a href="http://127.0.0.1/" target="_blank">127.0.0.1</a>) with exit status 32767.<br>
> ><br>> -------------------------------------------------------------------------------<br>> > <br>> > now i use mpirun -c 2, otherwise it uses only one processor. It seems that<br>> with constraint forces it's impossible to work on two processes together. <br>
> > Before to have all these problem I didn't use mpirun, I didn't use grompp<br>> -np 2..... <br>> > Before infact I had only one process on two processors.....<br>> > what can I do?<br>> > Thanks one more time<br>
> > Beniamino<br>> > <br>> > <br>> <br>> _______________________________________________<br>> gmx-users mailing list <a href="mailto:gmx-users@gromacs.org" target="_blank">gmx-users@gromacs.org</a><br>
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