From: Jorge Rodriguez <jrodr196@fiu.edu>
To: Bruce Momjian <bruce@momjian.us>,
        Frits Hoogland
	<frits.hoogland@gmail.com>
CC: Joe Conway <mail@joeconway.com>, Priya V <mailme0216@gmail.com>,
        "pgsql-performance@lists.postgresql.org"
	<pgsql-performance@lists.postgresql.org>
Subject: Re: Safe vm.overcommit_ratio for Large Multi-Instance PostgreSQL
 Fleet
Thread-Topic: Safe vm.overcommit_ratio for Large Multi-Instance PostgreSQL
 Fleet
Thread-Index: 
 AQHcBiqfbm5eBC7J1kKBy0FYhtQY/rRUZ9WAgADpUYCAAHZ2gIAAC9SAgABOcQCACTStAIAEi68/
Date: Fri, 15 Aug 2025 15:14:32 +0000
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References: <f35cdf25-411f-4cbc-a877-85569cf78061@joeconway.com>
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________________________________
From: Bruce Momjian <bruce@momjian.us>
Sent: Tuesday, August 12, 2025 1:49:26 PM
To: Frits Hoogland <frits.hoogland@gmail.com>
Cc: Joe Conway <mail@joeconway.com>; Priya V <mailme0216@gmail.com>; pgsql-=
performance@lists.postgresql.org <pgsql-performance@lists.postgresql.org>
Subject: Re: Safe vm.overcommit_ratio for Large Multi-Instance PostgreSQL F=
leet

Note: This message originated from outside the FIU Faculty/Staff email syst=
em.


On Wed, Aug  6, 2025 at 11:14:34PM +0200, Frits Hoogland wrote:
> > As I said, do not disable swap. You don't need a huge amount, but maybe=
 16 GB or so would do it.
>
> Joe, please, can you state a technical reason for saying this?
> All you are saying is =91don=92t do this=92.
>
> I=92ve stated my reasons for why this doesn=92t make sense, and you don=
=92t give any reason.
>
> The article you cite does seem to point to general usage, not database us=
age.

Here is a blog entry about it from 2012:

        https://urldefense.com/v3/__https://momjian.us/main/blogs/pgblog/20=
12.html*July_25_2012__;Iw!!FjuHKAHQs5udqho!KYC_U3_OpOjplPgrQZatREvJ8Ft3U7O3=
0Lh6SH0uGMsTcYagWyupQLofwkNLDhhxgmzWzl6blB1HpFk0oj4$

--
  Bruce Momjian  <bruce@momjian.us>        https://urldefense.com/v3/__http=
s://momjian.us__;!!FjuHKAHQs5udqho!KYC_U3_OpOjplPgrQZatREvJ8Ft3U7O30Lh6SH0u=
GMsTcYagWyupQLofwkNLDhhxgmzWzl6blB1H1-eyJ3I$
  EDB                                      https://urldefense.com/v3/__http=
s://enterprisedb.com__;!!FjuHKAHQs5udqho!KYC_U3_OpOjplPgrQZatREvJ8Ft3U7O30L=
h6SH0uGMsTcYagWyupQLofwkNLDhhxgmzWzl6blB1HJNHkhfc$

  Do not let urgent matters crowd out time for investment in the future.


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<div id=3D"divRplyFwdMsg" dir=3D"ltr"><font face=3D"Calibri, sans-serif" st=
yle=3D"font-size:11pt" color=3D"#000000"><b>From:</b> Bruce Momjian &lt;bru=
ce@momjian.us&gt;<br>
<b>Sent:</b> Tuesday, August 12, 2025 1:49:26 PM<br>
<b>To:</b> Frits Hoogland &lt;frits.hoogland@gmail.com&gt;<br>
<b>Cc:</b> Joe Conway &lt;mail@joeconway.com&gt;; Priya V &lt;mailme0216@gm=
ail.com&gt;; pgsql-performance@lists.postgresql.org &lt;pgsql-performance@l=
ists.postgresql.org&gt;<br>
<b>Subject:</b> Re: Safe vm.overcommit_ratio for Large Multi-Instance Postg=
reSQL Fleet</font>
<div>&nbsp;</div>
</div>
<div class=3D"BodyFragment"><font size=3D"2"><span style=3D"font-size:11pt;=
">
<div class=3D"PlainText">Note: This message originated from outside the FIU=
 Faculty/Staff email system.<br>
<br>
<br>
On Wed, Aug&nbsp; 6, 2025 at 11:14:34PM +0200, Frits Hoogland wrote:<br>
&gt; &gt; As I said, do not disable swap. You don't need a huge amount, but=
 maybe 16 GB or so would do it.<br>
&gt;<br>
&gt; Joe, please, can you state a technical reason for saying this?<br>
&gt; All you are saying is =91don=92t do this=92.<br>
&gt;<br>
&gt; I=92ve stated my reasons for why this doesn=92t make sense, and you do=
n=92t give any reason.<br>
&gt;<br>
&gt; The article you cite does seem to point to general usage, not database=
 usage.<br>
<br>
Here is a blog entry about it from 2012:<br>
<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <a href=3D"https://urldefense.co=
m/v3/__https://momjian.us/main/blogs/pgblog/2012.html*July_25_2012__;Iw!!Fj=
uHKAHQs5udqho!KYC_U3_OpOjplPgrQZatREvJ8Ft3U7O30Lh6SH0uGMsTcYagWyupQLofwkNLD=
hhxgmzWzl6blB1HpFk0oj4$">
https://urldefense.com/v3/__https://momjian.us/main/blogs/pgblog/2012.html*=
July_25_2012__;Iw!!FjuHKAHQs5udqho!KYC_U3_OpOjplPgrQZatREvJ8Ft3U7O30Lh6SH0u=
GMsTcYagWyupQLofwkNLDhhxgmzWzl6blB1HpFk0oj4$</a><br>
<br>
--<br>
&nbsp; Bruce Momjian&nbsp; &lt;bruce@momjian.us&gt;&nbsp;&nbsp;&nbsp;&nbsp;=
&nbsp;&nbsp;&nbsp; <a href=3D"https://urldefense.com/v3/__https://momjian.u=
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LofwkNLDhhxgmzWzl6blB1H1-eyJ3I$">
https://urldefense.com/v3/__https://momjian.us__;!!FjuHKAHQs5udqho!KYC_U3_O=
pOjplPgrQZatREvJ8Ft3U7O30Lh6SH0uGMsTcYagWyupQLofwkNLDhhxgmzWzl6blB1H1-eyJ3I=
$</a><br>
&nbsp; EDB&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&n=
bsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp=
;&nbsp; <a href=3D"https://urldefense.com/v3/__https://enterprisedb.com__;!=
!FjuHKAHQs5udqho!KYC_U3_OpOjplPgrQZatREvJ8Ft3U7O30Lh6SH0uGMsTcYagWyupQLofwk=
NLDhhxgmzWzl6blB1HJNHkhfc$">
https://urldefense.com/v3/__https://enterprisedb.com__;!!FjuHKAHQs5udqho!KY=
C_U3_OpOjplPgrQZatREvJ8Ft3U7O30Lh6SH0uGMsTcYagWyupQLofwkNLDhhxgmzWzl6blB1HJ=
NHkhfc$</a><br>
<br>
&nbsp; Do not let urgent matters crowd out time for investment in the futur=
e.<br>
<br>
<br>
</div>
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