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<p>Dear Peter,<br>
about the speed of gfortran+OpenBLAS and ifort+mkl:<br>
<br>
In my previous message I used the 8-thread processors i7 and xeon, respectively. When the same test is repeated on the same xeon machine, computing time is 132 min and 138 min, respectively.<br>
<br>
An amazing and hopeful result for poor researchers.<br>
<br>
Most of the computing time is consumed in lapw0, lapw1, and lapw2. The following table shows the storage occupied by the corresponding binary files,<br>
<br>
binary gfortran+OpenBLAS ifort+mkl<br>
lapw0 568 kB 2.2 MB<br>
lapw1 344 kB 1.9 MB<br>
lapw2 490 kB 2.2 MB<br>
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The present test seems to indicate that the code refinement of ifort relative to gfortran is counterproductive for WIEN2k. But is the test result generally valid? More WIEN2k experience than mine is required for a response.<br>
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Best regards / John<br>
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<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" color="#000000" face="Calibri, sans-serif"><b>From:</b> Wien <wien-bounces@zeus.theochem.tuwien.ac.at> on behalf of "Niedermayr, Arthur" <a.niedermayr@protonmail.com><br>
<b>Sent:</b> Wednesday, December 7, 2016 2:34 PM<br>
<b>To:</b> A Mailing list for WIEN2k users<br>
<b>Subject:</b> Re: [Wien] WIEN2k and gfortran</font>
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<div>Hello Mr. Rundgren,<br>
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<div>I wanted to ask you, <b>why do I need</b> the link <b>/opt/OpenBLAS/include</b> in linker flags?<br>
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<div>And what about <b>-lgfortran</b>, <b>-lpthread</b> and "<b>-I</b>" option?<u> What are they doing?</u><br>
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<div>I am also using OpenBLAS with following options (without compilation errors):<br>
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<div>L Linker Flags: $(FOPT) -L../SRC_lib -L/opt/OpenBLAS/lib<br>
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<div>R R_LIB (LAPACK+BLAS): -llapack_lapw -lopenblas<br>
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<div><u><i>Could I improve the calculation time of my program if I use your options?</i></u><br>
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<div>Best regards<br>
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<div>Arthur Niedermayr<br>
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<div>Ps. I thought that the OpenBLAS library only replaces the BLAS library, but not the LAPACK library.<br>
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<div>-------- Original Message --------<br>
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<div>Subject: [Wien] WIEN2k and gfortran<br>
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<div>Local Time: 5. Dezember 2016 11:54 AM<br>
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<div>UTC Time: 5. Dezember 2016 10:54<br>
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<div>From: jru@kth.se<br>
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<div>To: wien@zeus.theochem.tuwien.ac.at <wien@zeus.theochem.tuwien.ac.at><br>
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<div>Dear WIEN2k team,<br>
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<div>siteconfig and User's Guide can be updated concerning gfortran and BLAS:<br>
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<div> L Linker Flags: $(FOPT) -I /opt/OpenBLAS/include -L/opt/OpenBLAS/lib<br>
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<div> R R_LIB (LAPACK+BLAS): -lopenblas -lpthread -lgfortran<br>
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<div>OpenBLAS being available from the sites<br>
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<div>www.openblas.net and https://github.com/xianyi/OpenBLAS/wiki/Installation-Guide<br>
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<div>In a test taking 2.5 h/iteration gfortran/ifort time was 1.3. A current test got interesting when one of my disks containing ifort crashed.<br>
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<div>Regards,<br>
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<div>John Rundgren <span class="size" style="font-size:13px"></span><br>
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