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help / color / mirror / Atom feedFrom: johannes graën <johannes@selfnet.de>
To: Pavel Stehule <pavel.stehule@gmail.com>
Cc: pgsql-performance@postgresql.org <pgsql-performance@postgresql.org>
Subject: Re: performance drop after upgrade (9.6 > 10)
Date: Tue, 24 Oct 2017 16:15:59 +0200
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Hi Pavel, *,
you were right with ANALYZing the DB first. However, even after doing
so, I frequently see Seq Scans where an index was used before. This
usually cooccurs with parallelization and looked different before
upgrading to 10. I can provide an example for 10 [1], but I cannot
generate a query plan for 9.6 anymore.
Any ideas what makes the new version more seqscanny?
[1] https://explain.depesz.com/s/gXD3
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To: pgsql-performance@postgresql.org
Cc: johannes@selfnet.de, pavel.stehule@gmail.com
Subject: Re: performance drop after upgrade (9.6 > 10)
In-Reply-To: <CA++JNSfTEifSiBq73zpGCQuDNGr9yYcjmkx_=LtAbnadKLY_vg@mail.gmail.com>
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