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<p style="margin: 0; padding: 0;">Hi Bruce -</p>
<p style="margin: 0; padding: 0;"> </p>
<p style="margin: 0; padding: 0;"> Thanks for this opportunity to look more
carefully at a crucial topic .. </p>
<p style="margin: 0; padding: 0;">Please document the BASE_OS,
PostgreSQL_VERSION, postgres conf settings, versions of dependent libs and</p>
<p style="margin: 0; padding: 0;">hardware involved .. tablespace physical disk,
RAM, CPU model.. Its a bit of work, but important !</p>
<p style="margin: 0; padding: 0;"> </p>
<p style="margin: 0; padding: 0;"> from that base, the PostGIS BRANCH and
VERSION can be varied. Perhaps PostgreSQL itself as well.</p>
<p style="margin: 0; padding: 0;">The values there might be recorded in some
tabular format, including the results -> per test suite.</p>
<p style="margin: 0; padding: 0;"> </p>
<p style="margin: 0; padding: 0;">You probably know about the fine site
https://explain.depesz.com/ which can add detail to your EXPLAIN
findings.</p>
<p style="margin: 0; padding: 0;"> </p>
<p style="margin: 0; padding: 0;"> best regards from Berkeley, California</p>
<p style="margin: 0; padding: 0;"> --Brian</p>
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<p style="margin: 0; padding: 0;"><br>On Tue, 19 Feb 2019 09:59:12 -0800, Bruce
Rindahl <bruce.rindahl@gmail.com> wrote:</p>
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<div>I now have my cluster setup for testing with multiple small
computers with a full PostgreSQL/PostGIS installation. Using this I ran some
quick tests to find what cost on the ST_Area function kicks into parallel
mode. Using data/queries by Paul Ramsey at:
<div><a href="http://blog.cleverelephant.ca/2017/11/parallel-postgis-2A.html" target="">http://blog.cleverelephant.ca/2017/11/parallel-postgis-2A.html</a>
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<div>It kicks into parallel mode at cost = 66. I can easily test other
functions/configuration.</div>
<div> If this can help, let me know
<div>Thanks</div>
<div>Bruce</div>
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<br><hr>
<br> _______________________________________________<br> postgis-devel mailing
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</blockquote>
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<p><br> --<br>Brian M Hamlin<br> OSGeo California<br> blog.light42.com<br></p>
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