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<p class="MsoNormal">HI Kihang,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">“LD_PRELOAD” mainly is used to tell dynamic linker to pre-bind symbols rather than to cache the loading. I don’t think it can gain you the benefits as you described.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">As for tips for accelerating parallel programs, that is too broad a topic. Any tips I gave here would be just some random tips that may or may not be relevant to you. If you describe your actual applications, we may be able to give some
more specific tips.<o:p></o:p></p>
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<p class="MsoNormal">-- <br>
Hui Zhou<o:p></o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">Kihang Youn via discuss <discuss@mpich.org><br>
<b>Reply-To: </b>"discuss@mpich.org" <discuss@mpich.org><br>
<b>Date: </b>Tuesday, April 21, 2020 at 11:26 PM<br>
<b>To: </b>"discuss@mpich.org" <discuss@mpich.org><br>
<b>Cc: </b>Kihang Youn <kyoun@lenovo.com><br>
<b>Subject: </b>[mpich-discuss] Preloading the libraries "LD_PRELOAD" Effect<o:p></o:p></span></p>
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<p class="MsoNormal" style="background:white"><span style="font-size:12.0pt;color:black">Hi, everyone.<br>
<br>
I'd like to know about the MPICH mpirun environment option "LD_PRELOAD".<br>
Is the function of this option used to put the library on Cache (or RAM?) at startup and to gain benefits from multiple calls?<o:p></o:p></span></p>
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<pre style="background:white"><span style="color:black">3. For Fortran programs, you must also modify LD_PRELOAD<o:p></o:p></span></pre>
<pre style="background:white"><span style="color:black"> export LD_PRELOAD=/path/to/intel/lib/libmpi.so:/path/to/intel/lib/libmpigf.so:$LD_PRELOAD<o:p></o:p></span></pre>
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<p class="MsoNormal" style="background:white"><span style="font-size:12.0pt;color:black"><br>
Our team is looking for a way to load the library used by programs running through the "vmtouch" into the cache when performing the model, and we would like to know if it can be implemented through the "LD_PRELOAD" option.<br>
<br>
The second question may be a lazy one.<br>
Is there any options on tuning factor that can adjust parallel performance with MPICH?<br>
I'm actually only familiar with using MPI because I'm a newbie and I don't know much about performance enhancement, but I'm going to organize the list of recommendable performance-related options with MPICH and test them, so I'd like to know if there's anything
organized(PDF or URL or something).<br>
<br>
Thank you.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:#0C64C0">Kihang Youn(</span></b><b><span style="font-size:12.0pt;font-family:"Malgun Gothic",sans-serif;color:#0C64C0">윤기항</span></b><b><span style="font-size:12.0pt;color:#0C64C0">)</span></b><span style="font-size:12.0pt;color:black"> -
Application Analyst | Lenovo DCG Professional Services <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">Mobile: +82-10-9374-9396<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt;color:black">E-mail: kyoun@lenovo.com<o:p></o:p></span></p>
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