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From: Justin <zzzzz.graf@gmail.com>
Date: Tue, 9 Sep 2025 15:42:30 -0400
Message-ID: <CALL-XeNqwTVJpjadqqL_ws965C_1EuP0wxrEu78AFTK+Tx5rRA@mail.gmail.com>
Subject: Re: LWLock SerializableFinishedList
To: Alec Cozens <acozens@pixelpower.com>
Cc: "pgsql-general@postgresql.org" <pgsql-general@postgresql.org>
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Also reviewing if we really need SERIALIZED and could instead use READ
COMMITTED. Would that be likely to mitigate against this happening?

PostgreSQL can NOT  go below READ COMMITTED in transaction isolation
levels.  Read Committed is the default mode for all transactions in
PostgreSQL

https://www.postgresql.org/docs/17/transaction-iso.html

Unless there is a very specific need for serializing transactions such as
financial calculations or updating and calculating  the remaining number of
tickets to sell for a concert,  Serialization adds a lot of overhead for
not much gain..

thanks

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<div dir=3D"ltr"><div dir=3D"ltr">Also reviewing if we really need SERIALIZ=
ED and could instead use READ COMMITTED. Would that be likely to mitigate a=
gainst this happening?<br><br>PostgreSQL can NOT=C2=A0 go below READ COMMIT=
TED in transaction isolation levels.=C2=A0 Read Committed is the default mo=
de for all transactions in PostgreSQL=C2=A0<br><br><a href=3D"https://www.p=
ostgresql.org/docs/17/transaction-iso.html">https://www.postgresql.org/docs=
/17/transaction-iso.html</a>=C2=A0=C2=A0<br><br>Unless there is a very spec=
ific need for serializing=C2=A0transactions=C2=A0such as financial=C2=A0cal=
culations or updating and calculating=C2=A0 the remaining number of tickets=
 to sell for a concert,=C2=A0 Serialization adds a lot=C2=A0of overhead for=
 not much gain..=C2=A0<br><br>thanks=C2=A0</div></div>

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