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From: Soni M <diptatapa@gmail.com>
Date: Wed, 6 Sep 2017 15:12:26 +0700
Message-ID: 
 <CAAMgDXkDgmnnzdDtk1pOX473eLK=eQN+MnccncGHiNBAtiRnTw@mail.gmail.com>
Subject: OS cache management
To: "pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>
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Hello All, I would like to know about how OS cache works for postgres table
and index file.

Let's say I have 10 year data, and commonly used data only the last 1 year.
This data is quite big, so each table and index file is divided into
several file in PGDATA/base

Let's say 1 index named order_by_date has relfilenode = 1870772348, and
it's file consist of 1870772348, 1870772348.1, and 1870772348.2

And for oftenly queried 1 year data, do ALL files for the order_by_date
pushed to OS cache ? or it's just 1 file that contains index to this 1 year
data.

How about index named order_by_customer, will ALL the index files pushed to
OS cache ?

Can someone please explain about how OS cache works for this condition.

Thanks very much for the explanation.

-- 
Regards,

Soni Maula Harriz

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<div dir=3D"ltr">Hello All, I would like to know about how OS cache works f=
or postgres table and index file.<div><br></div><div>Let&#39;s say I have 1=
0 year data, and commonly used data only the last 1 year. This data is quit=
e big, so each table and index file is divided into several file in PGDATA/=
base</div><div><br></div><div>Let&#39;s say 1 index named order_by_date has=
 relfilenode =3D=C2=A01870772348, and it&#39;s file consist of=C2=A01870772=
348, 1870772348.1, and 1870772348.2</div><div><br></div><div>And for oftenl=
y queried 1 year data, do ALL files for the order_by_date pushed to OS cach=
e ? or it&#39;s just 1 file that contains index to this 1 year data.</div><=
div><br></div><div>How about index named order_by_customer, will ALL the in=
dex files pushed to OS cache ?</div><div><br></div><div>Can someone please =
explain about how OS cache works for this condition.</div><div><br></div><d=
iv>Thanks very much for the explanation.</div><div><br></div><div>-- <br><d=
iv class=3D"gmail_signature"><div dir=3D"ltr"><div>Regards,</div><div><br><=
/div>Soni Maula Harriz</div></div>
</div></div>

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