<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 15 (filtered medium)"><style><!--
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</o:shapelayout></xml><![endif]--></head><body lang=ES link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>After installed Pgpool with 2 postgresql nodes with streaming replication, I have noticed that access directly to postgresql is more efficient than through pgpool.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I supposed that load balance could increase the transactions per second executed because each node could receive more load, but the results shown below are not expected.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This is the setup:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Pgpool 3.6.1 whit connection pooling, streaming replication mode and load balancing mode.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>2 PostgreSQL server 9.6.1 whit streaming replication.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>For the tests I used sysbench and pgbench.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The results of sysbench:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><table class=MsoTableGrid border=1 cellspacing=0 cellpadding=0 width=543 style='width:407.0pt;border-collapse:collapse;border:none'><tr style='height:15.0pt'><td width=223 nowrap valign=top style='width:167.0pt;border:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal><span style='color:black;mso-fareast-language:ES'>Concurrent Users<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border:solid windowtext 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>1<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border:solid windowtext 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>20<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border:solid windowtext 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>50<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border:solid windowtext 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>100<o:p></o:p></span></p></td></tr><tr style='height:15.0pt'><td width=223 nowrap valign=top style='width:167.0pt;border:solid windowtext 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal><span style='color:black;mso-fareast-language:ES'>PostgreSQL (TPS) Direct<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>1166<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>20936<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>25743<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>27344<o:p></o:p></span></p></td></tr><tr style='height:15.0pt'><td width=223 nowrap valign=top style='width:167.0pt;border:solid windowtext 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal><span style='color:black;mso-fareast-language:ES'>Pgpool (TPS)<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>2240<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>7628<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>7013<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>6135<o:p></o:p></span></p></td></tr></table><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The results of pgbench<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><table class=MsoTableGrid border=1 cellspacing=0 cellpadding=0 width=457 style='width:343.0pt;border-collapse:collapse;border:none'><tr style='height:15.0pt'><td width=137 nowrap valign=top style='width:103.0pt;border:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'></td><td width=80 nowrap valign=top style='width:60.0pt;border:solid windowtext 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>1<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border:solid windowtext 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>20<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border:solid windowtext 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>50<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border:solid windowtext 1.0pt;border-left:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>100<o:p></o:p></span></p></td></tr><tr style='height:15.0pt'><td width=137 nowrap valign=top style='width:103.0pt;border:solid windowtext 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal><span style='color:black;mso-fareast-language:ES'>PostgreSQL (TPS) Direct<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>1403<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>6805<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>6194<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>5726<o:p></o:p></span></p></td></tr><tr style='height:15.0pt'><td width=137 nowrap valign=top style='width:103.0pt;border:solid windowtext 1.0pt;border-top:none;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal><span style='color:black;mso-fareast-language:ES'>Pgpool (TPS)<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>511<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>5430<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>5528<o:p></o:p></span></p></td><td width=80 nowrap valign=top style='width:60.0pt;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0cm 5.4pt 0cm 5.4pt;height:15.0pt'><p class=MsoNormal align=right style='text-align:right'><span style='color:black;mso-fareast-language:ES'>4705<o:p></o:p></span></p></td></tr></table><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>As you can see in both cases even with load balance, the total transactions per second are lower.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is this the expected behavior. Is there any way to allow more TPS when pgpool is used?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>There are other publications with similar results:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><a href="https://www.os3.nl/_media/2011-2012/courses/lia/rory_breuk_gerrie_veerman_-_report.pdf">https://www.os3.nl/_media/2011-2012/courses/lia/rory_breuk_gerrie_veerman_-_report.pdf</a> (page 28)<o:p></o:p></p><p class=MsoNormal><a href="http://www.mail-archive.com/pgpool-general@pgfoundry.org/msg03326.html">http://www.mail-archive.com/pgpool-general@pgfoundry.org/msg03326.html</a><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Regards<o:p></o:p></p></div></body></html>