<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">Thanks for the clarification.<div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Jul 9, 2017, at 7:05 AM, Mark Adams <<a href="mailto:mfadams@lbl.gov" class="">mfadams@lbl.gov</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><div dir="ltr" class=""><div class="gmail_extra"><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 style="word-wrap:break-word" class=""><div dir="auto" style="word-wrap:break-word" class=""><div dir="auto" style="word-wrap:break-word" class=""><br class=""><div class=""><br class=""></div><div class="">What are the differences between gamg and mg with -pc_mg_galerkin option (apart from the default smoother/coarse grid solver options, which I identified by comparing the ksp_view output)? Perhaps there’s an issue with the restriction, as you suggest?</div></div></div></div></blockquote><div class=""><br class=""></div><div class=""><br class=""></div><div class="">Not sure if this got answered. GAMG is for unstructured problems. A "pure" AMG method. </div><div class=""><br class=""></div><div class="">mg with -pc_mg_galerkin is semi-AMG, it still has geometric interpolation, and it is generally better if you can use it.<br class=""></div></div></div></div>
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