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Date: Wed, 29 Jan 2020 17:58:57 +0800
From: "movead.li@highgo.ca" <movead.li@highgo.ca>
To: "Kyotaro Horiguchi" <horikyota.ntt@gmail.com>
Cc: bruce <bruce@momjian.us>,
	ahsan.hadi <ahsan.hadi@highgo.ca>,
	robertmhaas <robertmhaas@gmail.com>,
	thomas.munro <thomas.munro@gmail.com>,
	pgsql-hackers <pgsql-hackers@postgresql.org>,
	sfrost <sfrost@snowman.net>
Subject: Re: Append with naive multiplexing of FDWs
References: <20200115204104.GC7201@momjian.us>,
	<20200116.155002.263144408387928025.horikyota.ntt@gmail.com>,
	<16ff008362d.edad0e7a133214.1991835179355654367@highgo.ca>,
	<20200129.173935.1752784195747118665.horikyota.ntt@gmail.com>
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<html><head><meta http-equiv=3D"content-type" content=3D"text/html; charse=
t=3DGB2312"><style>body { line-height: 1.5; }blockquote { margin-top: 0px;=
 margin-bottom: 0px; margin-left: 0.5em; }body { font-size: 10.5pt; font-f=
amily: =CE=A2=C8=ED=D1=C5=BA=DA; color: rgb(0, 0, 0); line-height: 1.5; }<=
/style></head><body>=0A<div><span></span>Hello,</div><div><br></div>=0A<bl=
ockquote style=3D"margin-Top: 0px; margin-Bottom: 0px; margin-Left: 0.5em"=
><div><span style=3D"font-size: 10.5pt; line-height: 1.5; background-color=
: transparent;">&gt;It is "asynchronous append on async-capable'd postgres=
-fdw scans". It</span></div>=0A&gt;<span style=3D"font-size: 10.5pt; line-=
height: 1.5; background-color: transparent;">could be called as such in th=
e sense that it is intended to be used</span>=0A<div>&gt;with sharding.</d=
iv>=0A<div>&nbsp;Yes that's it.</div>=0A<div><br></div>=0A<div>&nbsp;</div=
>=0A<div>&gt;Did you looked at my benchmarking result upthread?&nbsp; Even=
 it gives</div>=0A<div>&gt;significant gain even when gathering large numb=
er of tuples from</div>=0A<div>&gt;multiple servers or even from a single =
server.&nbsp; It is because of its</div>=0A<div>&gt;asynchronous nature.</=
div><div>I mean it gain performance at first, but it mets bottleneck while=
</div><div>increase&nbsp;<span style=3D"font-size: 10.5pt; line-height: 1.=
5; background-color: transparent;">the number of the nodes.</span></div><d=
iv><span style=3D"font-size: 10.5pt; line-height: 1.5; background-color: t=
ransparent;">For example:</span></div><div><span style=3D"color: rgb(0, 0,=
 0); background-color: rgba(0, 0, 0, 0);">&nbsp; &nbsp;It has 2 nodes, it =
will gain 200% performance.</span></div><div><span style=3D"color: rgb(0, =
0, 0); background-color: rgba(0, 0, 0, 0);">&nbsp; &nbsp;It has 3 nodes,&n=
bsp;</span><span style=3D"font-size: 10.5pt; line-height: 1.5; background-=
color: transparent;">it will gain 300% performance.</span></div><div><span=
 style=3D"color: rgb(0, 0, 0); background-color: rgba(0, 0, 0, 0);">&nbsp;=
 &nbsp;However,</span></div><div><span style=3D"color: rgb(0, 0, 0); backg=
round-color: rgba(0, 0, 0, 0);">&nbsp; &nbsp;It has 4 nodes, it gain 300% =
performance.</span></div><span style=3D"color: rgb(0, 0, 0); background-co=
lor: rgba(0, 0, 0, 0);">&nbsp; &nbsp;</span><span style=3D"font-size: 10.5=
pt; line-height: 1.5; background-color: transparent;">It has 5 nodes, it g=
ain 300% performance.</span><div><span style=3D"color: rgb(0, 0, 0); backg=
round-color: rgba(0, 0, 0, 0);">&nbsp; &nbsp;...</span></div><div><span st=
yle=3D"color: rgb(0, 0, 0); background-color: rgba(0, 0, 0, 0);">&nbsp; &n=
bsp;&nbsp;</span></div>=0A<div>&nbsp;</div>=0A<div>----</div>=0A<div><span=
 style=3D"font-variant-ligatures: normal; orphans: 2; widows: 2; color: rg=
b(13, 10, 11); font-family: monospace, monospace; font-size: 10.7333px; wh=
ite-space: pre-wrap;">Highgo Software (Canada/China/Pakistan) </span><br s=
tyle=3D"font-variant-ligatures: normal; orphans: 2; widows: 2; box-sizing:=
 border-box; color: rgb(13, 10, 11); font-family: monospace, monospace; fo=
nt-size: 10.7333px; white-space: pre-wrap;"><span style=3D"font-variant-li=
gatures: normal; orphans: 2; widows: 2; color: rgb(13, 10, 11); font-famil=
y: monospace, monospace; font-size: 10.7333px; white-space: pre-wrap;">URL=
 : </span><a href=3D"http://www.highgo.ca/" rel=3D"nofollow" target=3D"_bl=
ank" style=3D"color: rgb(132, 0, 50); cursor: pointer; font-variant-ligatu=
res: normal; orphans: 2; widows: 2; box-sizing: border-box; text-decoratio=
n: none; font-weight: 600; font-family: monospace, monospace; font-size: 1=
0.7333px; white-space: pre-wrap;">www.highgo.ca</a><span style=3D"font-var=
iant-ligatures: normal; orphans: 2; widows: 2; color: rgb(13, 10, 11); fon=
t-family: monospace, monospace; font-size: 10.7333px; white-space: pre-wra=
p;"> </span><br style=3D"font-variant-ligatures: normal; orphans: 2; widow=
s: 2; box-sizing: border-box; color: rgb(13, 10, 11); font-family: monospa=
ce, monospace; font-size: 10.7333px; white-space: pre-wrap;"><span style=
=3D"font-variant-ligatures: normal; orphans: 2; widows: 2; color: rgb(13, =
10, 11); font-family: monospace, monospace; font-size: 10.7333px; white-sp=
ace: pre-wrap;">EMAIL: mailto:movead(dot)li(at)highgo(dot)ca</span></div>=
=0A</blockquote>=0A</body></html>
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