Date: Wed, 9 Oct 2019 01:42:26 +0200 (CEST)
From: Andreas Joseph Krogh <andreas@visena.com>
To: pgsql-performance@lists.postgresql.org
Message-ID: <VisenaEmail.0.be1ddf58563b9542.16dadbe454a@tc7-visena>
In-Reply-To: 
 <CAFoK1axtgKBb-K4ssJ5fiAZgX=abX2Eq-e0m+zXfFifNyg0P5g@mail.gmail.com>
Subject: Sv: Would SSD improve Index Only Scan performance by a lot?
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P=C3=A5 onsdag 09. oktober 2019 kl. 01:37:06, skrev Arya F <arya6000@gmail.=
com=20
<mailto:arya6000@gmail.com>>: As my table has gotten bigger, it takes longe=
r to=20
get a single row back when querying a row by its btree index. Right now the=
=20
database is running on a traditional HDD. SSDs have a much faster seek time=
=20
than traditional HDDs. Would switching to an SSD improve "Index Only Scan" =
time=20
greatly? by at least 3-4 times? It depends on whether the index is accessed=
=20
often or not (wrt. caching), and (of course) the size of the index, but yes=
 -=20
"cold access" to the index (or persistent data in general) ismuch faster wi=
th=20
SSD. -- Andreas Joseph Krogh CTO / Partner - Visena AS Mobile: +47 909 56 9=
63=20
andreas@visena.com <mailto:andreas@visena.com> www.visena.com=20
<https://www.visena.com>  <https://www.visena.com>
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<div>P=C3=A5 onsdag 09. oktober 2019 kl. 01:37:06, skrev Arya F &lt;<a href=
=3D"mailto:arya6000@gmail.com">arya6000@gmail.com</a>&gt;:</div>

<blockquote style=3D"border-left: 1px solid rgb(204, 204, 204); margin: 0pt=
 0pt 0pt 0.8ex; padding-left: 1ex;">
<div dir=3D"ltr">As my table has gotten bigger, it takes longer to get a si=
ngle row back when querying=C2=A0a row by its btree index.
<div>=C2=A0</div>

<div>Right now the database is running on a traditional HDD. SSDs have a mu=
ch faster seek time than traditional HDDs.=C2=A0</div>

<div>=C2=A0</div>

<div>Would switching to an SSD improve &quot;Index Only Scan&quot; time gre=
atly? by at least 3-4 times?</div>
</div>
</blockquote>

<div>=C2=A0</div>

<div>It depends on whether the index is accessed often or not (wrt. caching=
), and (of course) the size of the index, but yes - &quot;cold access&quot;=
 to the index (or persistent data in general)=C2=A0is=C2=A0<em>much</em>=C2=
=A0faster with SSD.</div>

<div>=C2=A0</div>

<div class=3D"visena-email-signature" data-visena-message-id=3D"&lt;VisenaE=
mail.0.be1ddf58563b9542.16dadbe454a@tc7-visena>">
<div>--
<div><span style=3D"font-family:arial,helvetica,sans-serif;"><strong>Andrea=
s Joseph Krogh</strong></span></div>

<div><span style=3D"font-family:arial,helvetica,sans-serif;">CTO / Partner<=
/span> - Visena AS</div>

<div><span style=3D"font-family:arial,helvetica,sans-serif;">Mobile: +47 90=
9 56 963</span></div>

<div><a href=3D"mailto:andreas@visena.com">andreas@visena.com</a></div>

<div><a href=3D"https://www.visena.com">www.visena.com</a></div>

<div style=3D"padding-top: 5px"><a href=3D"https://www.visena.com"><img alt=
=3D"" src=3D"cid:part_F1325119785510JDD0SJ"></a></div>
</div>
</div>

<div>=C2=A0</div>
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