<div dir="ltr"><div dir="ltr">On Wed, Apr 13, 2022 at 9:11 AM Mark Adams <<a href="mailto:mfadams@lbl.gov">mfadams@lbl.gov</a>> wrote:<br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Apr 13, 2022 at 8:56 AM Matthew Knepley <<a href="mailto:knepley@gmail.com" target="_blank">knepley@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div dir="ltr">On Wed, Apr 13, 2022 at 6:42 AM Mark Adams <<a href="mailto:mfadams@lbl.gov" target="_blank">mfadams@lbl.gov</a>> wrote:<br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">No, without overlap you have, let say: <div><div>core 1: 1:32, 1:32</div><div>core 2: 33:64, 33:64</div></div><div><br></div><div>Overlap will increase the size of each domain so you get:</div><div><div>core 1: 1:33, 1:33</div><div>core 2: 32:65, 32:65</div></div></div></blockquote><div><br></div><div>I do not think this is correct. Here is the algorithm. Imagine the matrix is a large graph. When you divide rows, you</div><div>can think of that as dividing the vertices into sets. If overlap = 1, it means start with my vertex set, and add all vertices</div><div>that are just 1 edge away from my set.</div></div></div></blockquote><div><br></div><div>I think that is what was said. You increase each subdomain by one row of vertices.</div><div>So in 1D, vertex 32 and 33 are in both subdomains and you have an overlap region of size 2. </div><div>They want an overlap region of size 1, vertex 33.</div></div></div></blockquote><div><br></div><div>This is true, but I did not think they specified a 1D mesh.</div><div><br></div><div> Matt</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div class="gmail_quote"><div><br></div><div> Thanks,</div><div><br></div><div> Matt</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div>What you want is reasonable but requires PETSc to pick a separator set, which is not well defined.</div><div>You need to build that yourself with gasm (I think) if you want this.</div><div><br></div><div>Mark</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Apr 13, 2022 at 3:17 AM Zhuo Chen <<a href="mailto:chenzhuotj@gmail.com" target="_blank">chenzhuotj@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">Hi,<div><br></div><div>I hope that everything is going well with everybody.</div><div><br></div><div>I have a question about the PCASMSetOverlap. If I have a 128x128 matrix and I use 4 cores with overlap=1. Does it mean that from core 1 to core 4, the block ranges are (starting from 1):</div><div><br></div><div>core 1: 1:33, 1:33</div><div>core 2: 33:65, 33:65</div><div>core 3: 65:97, 65:97</div><div>core 4: 95:128, 95:128</div><div><br></div><div>Or is it something else? I cannot tell from the manual.</div><div><br></div><div>Many thanks in advance.</div><div><br></div><div><br clear="all"><div><br></div>-- <br><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><font style="font-family:arial,sans-serif;font-size:12.8px" color="#000000">Zhuo Chen</font><div style="font-family:arial,sans-serif;font-size:12.8px"><font color="#000000">Department of Astronomy</font></div><div style="font-family:arial,sans-serif;font-size:12.8px"><font color="#000000">Tsinghua University</font></div><div style="font-family:arial,sans-serif;font-size:12.8px"><font color="#000000">Beijing, China 100084</font></div><div><font face="'comic sans ms', sans-serif"><font color="#000000"><u><a href="https://czlovemath123.github.io/" target="_blank">https://czlovemath123.github.io/</a></u></font><br></font></div></div></div></div></div></div></div></div>
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</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div>What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>-- Norbert Wiener</div><div><br></div><div><a href="http://www.cse.buffalo.edu/~knepley/" target="_blank">https://www.cse.buffalo.edu/~knepley/</a><br></div></div></div></div></div></div></div></div>
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</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div>What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>-- Norbert Wiener</div><div><br></div><div><a href="http://www.cse.buffalo.edu/~knepley/" target="_blank">https://www.cse.buffalo.edu/~knepley/</a><br></div></div></div></div></div></div></div></div>