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</o:shapelayout></xml><![endif]--></head><body lang=FR link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#1F497D'>Well, thanks, could be the explanation.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#1F497D'>I tried the query but I get SQLSTATE 53200, out of memory after a few seconds.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>De :</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> postgis-users [mailto:postgis-users-bounces@lists.osgeo.org] <b>De la part de</b> Marcone<br><b>Envoyé :</b> lundi 9 janvier 2017 15:31<br><b>À :</b> PostGIS Users Discussion<br><b>Objet :</b> Re: [postgis-users] CPU tuning<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>2017-01-09 12:21 GMT-02:00 Rémi Cura <<a href="mailto:remi.cura@gmail.com" target="_blank">remi.cura@gmail.com</a>>:<o:p></o:p></p><div><p class=MsoNormal><span style='font-family:"Courier New"'>postgres 9.4 is non-parallelised, what you see is that postgres use 100% of a core, but the core beig used is rotated,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'>which mean the average usage of your cpu is 100% / 4 (your number of core),<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-family:"Courier New"'>which might be the explaination for your 30%.<o:p></o:p></span></p></div></div><p class=MsoNormal><br>Exactly! I was write something like this.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Please, try the query:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal>FOR row in<o:p></o:p></p></div><div><p class=MsoNormal><span class=gmail-apple-tab-span> </span>SELECT DISTINCT ON (t_x.code, t_y.code)<o:p></o:p></p></div><div><p class=MsoNormal><span class=gmail-apple-tab-span> </span>t_x.code,<o:p></o:p></p></div><div><p class=MsoNormal><span class=gmail-apple-tab-span> </span>t_y.code,<o:p></o:p></p></div><div><p class=MsoNormal><span class=gmail-apple-tab-span> </span>ST_Distance(t_x.geom, t_y.geom)<o:p></o:p></p></div><div><p class=MsoNormal><span class=gmail-apple-tab-span> </span>FROM t_x, t_y<o:p></o:p></p></div><div><p class=MsoNormal><span class=gmail-apple-tab-span> </span>ORDER BY t_x.code,<o:p></o:p></p></div><div><p class=MsoNormal><span class=gmail-apple-tab-span> </span>t_y.code,<o:p></o:p></p></div><div><p class=MsoNormal><span class=gmail-apple-tab-span> </span>ST_Distance(t_x.geom, t_y.geom)<o:p></o:p></p></div><div><p class=MsoNormal>LOOP<o:p></o:p></p></div><div><p class=MsoNormal><span class=gmail-apple-tab-span> </span>-- Do something here<o:p></o:p></p></div><div><p class=MsoNormal>END LOOP;<o:p></o:p></p></div></div><div><p class=MsoNormal><br>The query above use less conversions, may be more efficient.<br clear=all><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></div>
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