<p>The reference BLAS is "bad", but unless you are doing dense linear algebra or using a third party solver that uses BLAS level 3 internally (MUMPS), a tuned implementation will make little difference because relatively little time will be spent in BLAS, and those operations are memory bound (and can only be improved a modest amount by trickery).</p>
<p><blockquote type="cite">On Feb 6, 2011 9:11 AM, "Gaurish Telang" <<a href="mailto:gaurish108@gmail.com">gaurish108@gmail.com</a>> wrote:<br><br>How good is the BLAS library that PETSc downloads with the option <span style="background-color:rgb(255, 255, 255)"> </span><span style="color:rgb(255, 0, 0);background-color:rgb(0, 0, 0)"><span style="background-color:rgb(255, 255, 255);color:rgb(0, 0, 0)">"--download-f-blas-lapack=1 " during the installation step ? <br>
<br>Is it recommended to use this BLAS library with PETSc or libraries such as ATLAS or GOTO? <br></span><span><span style="background-color:rgb(255, 255, 255)"></span></span></span>
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