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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I would like to understand why more memory is consumed by -pc_type gamg compared to -pc_type mg for the same problem size<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">ksp/ksp/tutorial: ./ex45 -da_grid_x 368 -da_grid_x 368 -da_grid_x 368 -ksp_type cg<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">-pc_type mg<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Maximum (over computational time) process memory: total 1.9399e+10 max 9.7000e+09 min 9.6992e+09<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">-pc_type gamg<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Maximum (over computational time) process memory: total 4.9671e+10 max 2.4836e+10 min 2.4835e+10<o:p></o:p></p>
<p class="MsoNormal">
<o:p></o:p></p>
<p class="MsoNormal">Am I right in understanding that the memory limiting factor is ‘max 2.4836e+10’ as it is the maximum memory used at any given time?<o:p></o:p></p>
<p class="MsoNormal">I have attached the -log_view output of both the preconditioners.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Best regards,<o:p></o:p></p>
<p class="MsoNormal">Karthik.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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