<html>#2882: Running BBH with CarpetX with CPUs: High memory consumption and low performance
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<tr><td style='text-align:right'> Reporter:</td><td>Alejandra Gonzalez</td></tr>
<tr><td style='text-align:right'> Status:</td><td>new</td></tr>
<tr><td style='text-align:right'>Milestone:</td><td></td></tr>
<tr><td style='text-align:right'> Version:</td><td></td></tr>
<tr><td style='text-align:right'> Type:</td><td>bug</td></tr>
<tr><td style='text-align:right'> Priority:</td><td>major</td></tr>
<tr><td style='text-align:right'>Component:</td><td>CarpetX</td></tr>
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<p>Hello,<br>
This ticket is due to concerns regarding the performance of CarpetX running <strong>with CPUs</strong> in the new machine MareNostrum 5.</p>
<p>The first issue I had was the memory needed to run a q=1 configuration, coming across several out-of-memory errors (regardless of the number of nodes requested). The standard nodes in MN5 have 2GB per core (112 cores per node), so I had to switch to the high memory ones to be able to make it run (this is the line `#SBATCH --constraint=highmem` in the attached batch file). Is this also the case for other machines? </p>
<p>The second issue is that now that is running (<code>ncells=128</code> and 1 node) it’s going awfully slow ~0.07 M/hr, less than I would expect from using one node. These type of binary configurations we have been running them in 2~4 nodes reaching speeds of around 4~7 M/hr with Carpet and at higher resolution. </p>
<p>Attached you find the parfile, batch file, and output.</p>
<p><table><tr><td>attachment:</td><td><a href="https://api.bitbucket.org/2.0/repositories/einsteintoolkit/tickets/issues/2882/attachments/q1.__0._0._0.8__0._0._0.8__e0.5.par">q1.__0._0._0.8__0._0._0.8__e0.5.par</a></td></tr>
<tr><td>attachment:</td><td><a href="https://api.bitbucket.org/2.0/repositories/einsteintoolkit/tickets/issues/2882/attachments/output.log">output.log</a></td></tr>
<tr><td>attachment:</td><td><a href="https://api.bitbucket.org/2.0/repositories/einsteintoolkit/tickets/issues/2882/attachments/run_cactus.sh">run_cactus.sh</a></td></tr>
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<p>--<br/>
Ticket URL: <a href='https://bitbucket.org/einsteintoolkit/tickets/issues/2882/running-bbh-with-carpetx-with-cpus-high'>https://bitbucket.org/einsteintoolkit/tickets/issues/2882/running-bbh-with-carpetx-with-cpus-high</a></p>
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