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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 have several questions regarding SIMD implementation in GROMACS and the future plans for it.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">First, I am wondering if there is any project being carried on about porting GROMACS to SVE for ARM architecture.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="margin-left:20.5pt;text-indent:-.25in;mso-list:l0 level1 lfo1">
<![if !supportLists]><span style="mso-list:Ignore">1)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Are the current plans to include SVE in GROMACS for SIMD acceleration in CPU?<o:p></o:p></p>
<p class="MsoListParagraph" style="margin-left:20.5pt;text-indent:-.25in;mso-list:l0 level1 lfo1">
<![if !supportLists]><span style="mso-list:Ignore">2)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Is there any free development branch where this is made?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Currently I am trying to extract the main kernels from GROMACS where SIMD instructions are performed in order to run them with SVE, reading the documentation and some articles I found that most of the SIMDs features are used in the force
computation (bonded, non-bonded and PME). By looking inside the code I identified that the function “do_nb_verlet” is consuming around 70 – 80% of the time in sequential and parallel executions. I am using an Arm-based processor and running the “ion_channel”
benchmark (Test Case A from the UEABS). I compiled GROMACS with Advanced NEON SIMD enabled.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoListParagraph" style="margin-left:20.5pt;text-indent:-.25in;mso-list:l0 level1 lfo1">
<![if !supportLists]><span style="mso-list:Ignore">3)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Is this routine responsible only of the non-bonded forces? Does the “nb” prefix indicate “non-bonded”?<o:p></o:p></p>
<p class="MsoListParagraph" style="margin-left:20.5pt;text-indent:-.25in;mso-list:l0 level1 lfo1">
<![if !supportLists]><span style="mso-list:Ignore">4)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Is this same effect (“do_nb_verlet” the most expensive) measured for others benchmarks?<o:p></o:p></p>
<p class="MsoListParagraph" style="margin-left:20.5pt;text-indent:-.25in;mso-list:l0 level1 lfo1">
<![if !supportLists]><span style="mso-list:Ignore">5)<span style="font:7.0pt "Times New Roman"">
</span></span><![endif]>Are there others ready-to-use and small benchmarks like the “ion_channel.tpr” available (<150K atoms)? Test Case B from UEABS (3.3 M atoms) is not suitable for my hardware resources.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks a lot, Guido.<b><span style="font-size:10.0pt;color:#666666"><o:p></o:p></span></b></p>
<p class="MsoNormal"><o:p> </o:p></p>
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