Date: Thu, 12 Dec 2024 12:27:44 +0000 (UTC)
From: SASIKUMAR Devaraj <sashikumard@yahoo.com>
To: Laurenz Albe <laurenz.albe@cybertec.at>,
	"David G. Johnston" <david.g.johnston@gmail.com>
Cc: Pgsql-admin <pgsql-admin@lists.postgresql.org>
Message-ID: <2060427903.1621547.1734006464981@mail.yahoo.com>
In-Reply-To: <52122541702b838b870bbd239008625aacc042dd.camel@cybertec.at>
References: <155477463.1496353.1733983706261.ref@mail.yahoo.com>
 <155477463.1496353.1733983706261@mail.yahoo.com>
 <CAKFQuway7Ly58D_e8UBaDR4hCw9T-2yvWiJ3+EZNzbvXoRWjMQ@mail.gmail.com>
 <52122541702b838b870bbd239008625aacc042dd.camel@cybertec.at>
Subject: Re: VacuumDB generating huge WAL filed
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Hi
Since it is generating 60GB in few mins, my replication lag is increasing u=
pto 10Gb for around 10 mins, which may seen as possible=C2=A0data loss in c=
ase of primary node failure=C2=A0
RegardsSasi


Sent from Yahoo Mail for iPhone


On Thursday, December 12, 2024, 12:06 PM, Laurenz Albe <laurenz.albe@cybert=
ec.at> wrote:

On Wed, 2024-12-11 at 23:25 -0700, David G. Johnston wrote:
> On Wednesday, December 11, 2024, SASIKUMAR Devaraj <sashikumard@yahoo.com=
> wrote:
> > When we are running vacuumdb for our database of 1.5TB it is generating=
 approximately 60GB
> > of WAL files? Any way we can reduce this WAL file generation?
>=20
> Set a much more aggressive autovacuum so you don=E2=80=99t accumulate as =
much dead tuples between runs?

You can also activate "wal_compression" for smaller full-page images
and increase "max_wal_size" to get fewer of them.

But 60GB of WAL shouldn't be a problem.=C2=A0 Why are they a problem for yo=
u?

Yours,
Laurenz Albe


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dy>
Hi<div><br></div><div>Since it is generating 60GB in few mins, my replicati=
on lag is increasing upto 10Gb for around 10 mins, which may seen as possib=
le&nbsp;data loss in case of primary node failure&nbsp;</div><div><br></div=
><div>Regards</div><div>Sasi<br><br><br><div class=3D"yahoo-signature"><a s=
tyle=3D"font-size:12px" href=3D"https://mail.onelink.me/107872968?pid=3Dnat=
iveplacement&amp;c=3DGlobal_Acquisition_YMktg_315_Internal_EmailSignature&a=
mp;af_sub1=3DAcquisition&amp;af_sub2=3DGlobal_YMktg&amp;af_sub3=3D&amp;af_s=
ub4=3D100000604&amp;af_sub5=3DEmailSignature__Static_">Sent from Yahoo Mail=
 for iPhone</a><br></div><br><p class=3D"yahoo-quoted-begin" style=3D"font-=
size: 15px; color: rgb(132, 115, 255); padding-top: 15px; margin-top: 0px;"=
>On Thursday, December 12, 2024, 12:06 PM, Laurenz Albe &lt;laurenz.albe@cy=
bertec.at&gt; wrote:</p><blockquote class=3D"iosymail"><div dir=3D"ltr">On =
Wed, 2024-12-11 at 23:25 -0700, David G. Johnston wrote:<div class=3D"yqt58=
88205171" id=3D"yqtfd32729"><br clear=3D"none">&gt; On Wednesday, December =
11, 2024, SASIKUMAR Devaraj &lt;<a shape=3D"rect" ymailto=3D"mailto:sashiku=
mard@yahoo.com" href=3D"mailto:sashikumard@yahoo.com">sashikumard@yahoo.com=
</a>&gt; wrote:<br clear=3D"none">&gt; &gt; When we are running vacuumdb fo=
r our database of 1.5TB it is generating approximately 60GB<br clear=3D"non=
e">&gt; &gt; of WAL files? Any way we can reduce this WAL file generation?<=
br clear=3D"none">&gt; <br clear=3D"none">&gt; Set a much more aggressive a=
utovacuum so you don=E2=80=99t accumulate as much dead tuples between runs?=
</div><br clear=3D"none"><br clear=3D"none">You can also activate "wal_comp=
ression" for smaller full-page images<br clear=3D"none">and increase "max_w=
al_size" to get fewer of them.<br clear=3D"none"><br clear=3D"none">But 60G=
B of WAL shouldn't be a problem.&nbsp; Why are they a problem for you?<br c=
lear=3D"none"><br clear=3D"none">Yours,<br clear=3D"none">Laurenz Albe<div =
class=3D"yqt5888205171" id=3D"yqtfd22218"><br clear=3D"none"><br clear=3D"n=
one"><br clear=3D"none"></div></div><blockquote></blockquote></blockquote><=
/div>
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