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    Hello Krishnendu,<br>
    <br>
    I saw there are k-points given by the output of pw.x:<br>
    <br>
    number of k points=    10  Methfessel-Paxton smearing, width (Ry)= 
    0.0600<br>
                           cart. coord. in units 2pi/alat<br>
            k(    1) = (   0.0000000   0.0000000   0.0000000), wk =  
    0.0312500<br>
            k(    2) = (   0.0000000   0.0000000   0.0833333), wk =  
    0.1875000<br>
            k(    3) = (   0.0000000   0.0000000  -0.1666667), wk =  
    0.0937500<br>
            k(    4) = (   0.0000000   0.0833333   0.0833333), wk =  
    0.3750000<br>
            k(    5) = (   0.0000000   0.0833333  -0.1666667), wk =  
    0.3750000<br>
            k(    6) = (   0.0000000  -0.1666667  -0.1666667), wk =  
    0.0937500<br>
            k(    7) = (   0.0833333   0.0833333   0.0833333), wk =  
    0.2500000<br>
            k(    8) = (   0.0833333   0.0833333  -0.1666667), wk =  
    0.3750000<br>
            k(    9) = (   0.0833333  -0.1666667  -0.1666667), wk =  
    0.1875000<br>
            k(   10) = (  -0.1666667  -0.1666667  -0.1666667), wk =  
    0.0312500<br>
    <br>
    <br>
    <br>
    But I am not sure how to exactly compare to the k-points generated
    by you.<br>
    However if you are interested, I think you can generate the list of
    k-points from my input. of My input is at the end of the email.<br>
    <br>
    Thank you.<br>
    <br>
    Best regards,<br>
    Xin<br>
    <br>
    <div class="moz-cite-prefix">On 31/10/2022 12:24, KRISHNENDU
      MUKHERJEE wrote:<br>
    </div>
    <blockquote type="cite" cite="mid:2055384572.12248237.1667211896975@nmlindia.org">
      
      <div style="font-family: arial, helvetica, sans-serif; font-size:
        style=" font-size:="" 12pt;="" color:="" #000000?="">
        <div><br>
        </div>
        <div>
          <div>Hello Xin,</div>
          <div><br>
          </div>
          <div>Thank you for your reply. I have made a new thread. Below
            is the k-points obtained from kpoints.x for BCC Bravais
            Lattice, for a 4 4 4 0 0 0 mesh, considering the 48
            symmetries. I hope this will be the same for the case with
            calculations for ibrav=3, with BCC primitive cell with one
            atom per cell.</div>
          <div>8 (=number of k_points)</div>
          <div><br>
          </div>
          <div>    1   0.0000000  0.0000000  0.0000000   1.00</div>
          <div>    2   0.2500000  0.0000000  0.2500000  12.00</div>
          <div>    3   0.5000000  0.0000000  0.5000000   6.00</div>
          <div>    4   0.2500000  0.2500000  0.5000000  24.00</div>
          <div>    5   0.0000000  0.0000000  0.5000000   6.00</div>
          <div>    6   0.2500000  0.0000000  0.7500000  12.00</div>
          <div>    7  -0.5000000  0.5000000  0.5000000   2.00</div>
          <div>    8   0.0000000  0.0000000  1.0000000   1.00</div>
          <div><br>
          </div>
          <div><br>
          </div>
          <div>Now let us compare with the k_points that were used in
            your calculation when a BCC supercell consisting of BCC Unit
            Cells is used as input with ibrav=0. So, I request you if
            you can kindly post the k_points considered in your
            calculation. Also you may kindly include your input script
            once more so that later on somebody can follow the
            discussion. </div>
          <div><br>
          </div>
          <div>Thanking you,</div>
          <div>Best regards,</div>
          <div>Krishnendu</div>
        </div>
        <div><br>
        </div>
        <div><br>
        </div>
        <hr id="zwchr" data-marker="__DIVIDER__">
        <div data-marker="__HEADERS__"><b>From: </b>"xin tlg jin"
          <a class="moz-txt-link-rfc2396E" href="mailto:xin.tlg.jin@outlook.com"><xin.tlg.jin@outlook.com></a><br>
          <b>To: </b><a class="moz-txt-link-abbreviated" href="mailto:users@lists.quantum-espresso.org">users@lists.quantum-espresso.org</a><br>
          <b>Cc: </b>"KRISHNENDU MUKHERJEE"
          <a class="moz-txt-link-rfc2396E" href="mailto:krishnendu@nmlindia.org"><krishnendu@nmlindia.org></a><br>
          <b>Sent: </b>Monday, October 31, 2022 12:28:24 PM<br>
          <b>Subject: </b>Re: [QE-users] Parallel computing of QE7.1
          vc-relax crashes when using large number of processors<br>
        </div>
        <br>
        <div data-marker="__QUOTED_TEXT__">Hello Krishnendu,<br>
          <br>
          Thank you for the message<br>
          Yes, we can start a separate thread. I didn't realize that
          there could be such a problem. <br>
          Actually, the reason that I use ibrav=0 for BCC W is that I
          want to put some interstitials inside if the program works.<br>
          <br>
          Best regards,<br>
          Xin<br>
           <br>
          <br>
          <div>On 30/10/2022 05:35, KRISHNENDU MUKHERJEE wrote:<br>
          </div>
          <blockquote>
            <div style="font-family:'arial' , 'helvetica' , sans-serif">
              <div><br>
              </div>
              <div>
                <div>Dear Xin Jin,</div>
                <div><br>
                </div>
                <div> Sorry that I have another matter to discuss. If
                  you wish we may start a separate thread on the subject
                  I am eager to discuss. I have some concern about your
                  script. If you want to do calculation for BCC W you
                  may need to use ibrav=3. Note that for ibrav=3 the
                  (primitive) lattice vectors are in the form:</div>
                <div><br>
                </div>
                <div>ibrav=3          cubic I (bcc)</div>
                <div>      v1 = (a/2)(1,1,1),  v2 = (a/2)(-1,1,1),  v3 =
                  (a/2)(-1,-1,1) which is inbuilt in QE (so that you
                  need not input CELL_PARAMETERS) and you only need to
                  put an atom in the position 0.00 0.00 0.00.</div>
                <div>With those input QE determines the k_points for BCC
                  Bravais Lattice.</div>
                <div><br>
                </div>
                <div>You have input the atomic positions in terms of
                  supercell made of BCC unit cell. And you have put
                  ibrav=0. With those input I am afraid most probably
                  the k_points generated would be that of a Simple Cubic
                  structure.</div>
                <div>What we can do is next week I would generate the
                  k_points for BCC with a mesh of 4 4 4 0 0 0 and post
                  it. And you can see whether it is matching with the
                  k_points considered in your calculation and discuss
                  further.</div>
                <div><br>
                </div>
                <div>Thank you,</div>
                <div>Best regards,</div>
                <div>Krishnendu</div>
              </div>
              <div><br>
              </div>
              <div>------------------------------------------------------------------------------------------------------------------------------------------</div>
              <div><br>
              </div>
              <div>
                <div>Xin Jin wrote on 28/Oct/2022 </div>
                <div><br>
                </div>
                <div><br>
                </div>
                <div>Dear Quantum Espresso Forum,</div>
                <div><br>
                </div>
                <div>I encountered a problem related to the parallel
                  computing using QE7.1 </div>
                <div>for vc-relax.</div>
                <div><br>
                </div>
                <div>I was trying to perform a vc-relax for a 3*3*3 BCC
                  tungsten super cell. </div>
                <div>The code works fine for non-parallel computing,
                  also works fine for </div>
                <div>parallel computing if the number of processors is
                  smaller than 10.</div>
                <div><br>
                </div>
                <div>However, if the number of processors is larger than
                  10, I will get </div>
                <div>following MPI error:</div>
                <div>/*** An error occurred in MPI_Comm_free//</div>
                <div>//*** reported by process [3585895498,2]//</div>
                <div>//*** on communicator MPI_COMM_WORLD//</div>
                <div>//*** MPI_ERR_COMM: invalid communicator//</div>
                <div>//*** MPI_ERRORS_ARE_FATAL (processes in this
                  communicator will now abort,//</div>
                <div>//***    and potentially your MPI job)/</div>
                <div><br>
                </div>
                <div>For parallel computing, I am using
                  /OpenMPI/3.1.4-gcccuda/. (In </div>
                <div>addition, it seems that If I use OpenMPI V4, the
                  simulation speed will </div>
                <div>be much slower than that of V3.)</div>
                <div><br>
                </div>
                <div>Another thing is that, if I decrease the size of
                  the supper cell, for </div>
                <div>example to 2*2*2, then there is no problem in the
                  parallel computing </div>
                <div>even if I use more than 30 processors.</div>
                <div><br>
                </div>
                <div>Could you help me look at this problem, please?</div>
                <div><br>
                </div>
                <div>The input for QE can be found below.</div>
                <div><br>
                </div>
                <div>Thank you in advance!</div>
                <div><br>
                </div>
                <div>Xin Jin</div>
                <div><br>
                </div>
                <div>/&control//</div>
                <div>//</div>
                <div>//    calculation='vc-relax' //</div>
                <div>//    restart_mode='from_scratch', //</div>
                <div>//    prefix='W_relax', //</div>
                <div>//    pseudo_dir="../../PP_files",//</div>
                <div>//    outdir='./'//</div>
                <div>//</div>
                <div>// ///</div>
                <div>////</div>
                <div>//</div>
                <div>// &system//</div>
                <div>//    ibrav= 0, //</div>
                <div>//    celldm(1)=5.972,//</div>
                <div>//    nat=  54, //</div>
                <div>//    ntyp= 1,//</div>
                <div>//    ecutwfc = 50,//</div>
                <div>//    ecutrho = 500,//</div>
                <div>//    occupations='smearing', smearing='mp',
                  degauss=0.06//</div>
                <div>// ///</div>
                <div>//</div>
                <div>// &electrons//</div>
                <div>//    diagonalization='david',//</div>
                <div>//    conv_thr =  1.0d-8,//</div>
                <div>//    mixing_beta = 0.5,//</div>
                <div>// ///</div>
                <div>////</div>
                <div>// &ions//</div>
                <div>// ///</div>
                <div>//</div>
                <div>// &cell//</div>
                <div>//    press = 0.0,//</div>
                <div>// ///</div>
                <div>////</div>
                <div>//ATOMIC_SPECIES//</div>
                <div>// W  183.84 W.pbe-spn-kjpaw_psl.1.0.0.UPF//</div>
                <div>////</div>
                <div>//CELL_PARAMETERS {alat}//</div>
                <div>//   3.0  0.0  0.0//</div>
                <div>//   0.0  3.0  0.0//</div>
                <div>//   0.0  0.0  3.0 //</div>
                <div>////</div>
                <div>//ATOMIC_POSITIONS {alat}//</div>
                <div>//W 0.00000 0.00000 0.00000//</div>
                <div>//W 0.50000 0.50000 0.50000//</div>
                <div>//W 1.00000 0.00000 0.00000//</div>
                <div>//W 1.50000 0.50000 0.50000//</div>
                <div>//W 2.00000 0.00000 0.00000//</div>
                <div>//W 2.50000 0.50000 0.50000//</div>
                <div>//W 0.00000 1.00000 0.00000//</div>
                <div>//W 0.50000 1.50000 0.50000//</div>
                <div>//W 1.00000 1.00000 0.00000//</div>
                <div>//W 1.50000 1.50000 0.50000//</div>
                <div>//W 2.00000 1.00000 0.00000//</div>
                <div>//W 2.50000 1.50000 0.50000//</div>
                <div>//W 0.00000 2.00000 0.00000//</div>
                <div>//W 0.50000 2.50000 0.50000//</div>
                <div>//W 1.00000 2.00000 0.00000//</div>
                <div>//W 1.50000 2.50000 0.50000//</div>
                <div>//W 2.00000 2.00000 0.00000//</div>
                <div>//W 2.50000 2.50000 0.50000//</div>
                <div>//W 0.00000 0.00000 1.00000//</div>
                <div>//W 0.50000 0.50000 1.50000//</div>
                <div>//W 1.00000 0.00000 1.00000//</div>
                <div>//W 1.50000 0.50000 1.50000//</div>
                <div>//W 2.00000 0.00000 1.00000//</div>
                <div>//W 2.50000 0.50000 1.50000//</div>
                <div>//W 0.00000 1.00000 1.00000//</div>
                <div>//W 0.50000 1.50000 1.50000//</div>
                <div>//W 1.00000 1.00000 1.00000//</div>
                <div>//W 1.50000 1.50000 1.50000//</div>
                <div>//W 2.00000 1.00000 1.00000//</div>
                <div>//W 2.50000 1.50000 1.50000//</div>
                <div>//W 0.00000 2.00000 1.00000//</div>
                <div>//W 0.50000 2.50000 1.50000//</div>
                <div>//W 1.00000 2.00000 1.00000//</div>
                <div>//W 1.50000 2.50000 1.50000//</div>
                <div>//W 2.00000 2.00000 1.00000//</div>
                <div>//W 2.50000 2.50000 1.50000//</div>
                <div>//W 0.00000 0.00000 2.00000//</div>
                <div>//W 0.50000 0.50000 2.50000//</div>
                <div>//W 1.00000 0.00000 2.00000//</div>
                <div>//W 1.50000 0.50000 2.50000//</div>
                <div>//W 2.00000 0.00000 2.00000//</div>
                <div>//W 2.50000 0.50000 2.50000//</div>
                <div>//W 0.00000 1.00000 2.00000//</div>
                <div>//W 0.50000 1.50000 2.50000//</div>
                <div>//W 1.00000 1.00000 2.00000//</div>
                <div>//W 1.50000 1.50000 2.50000//</div>
                <div>//W 2.00000 1.00000 2.00000//</div>
                <div>//W 2.50000 1.50000 2.50000//</div>
                <div>//W 0.00000 2.00000 2.00000//</div>
                <div>//W 0.50000 2.50000 2.50000//</div>
                <div>//W 1.00000 2.00000 2.00000//</div>
                <div>//W 1.50000 2.50000 2.50000//</div>
                <div>//W 2.00000 2.00000 2.00000//</div>
                <div>//W 2.50000 2.50000 2.50000//</div>
                <div>//</div>
                <div>//K_POINTS {automatic}//</div>
                <div>//4 4 4 0 0 0//</div>
                <div>/</div>
                <div>-------------- next part --------------</div>
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