From: Gnanakumar <gnanam@zoniac.com>
To: 'Tomas Vondra' <tv@fuzzy.cz>
Cc: 'Merlin Moncure' <mmoncure@gmail.com>
Cc: 'Kevin Grittner' <kevin.grittner@wicourts.gov>
Cc: pgsql-performance@postgresql.org
Subject: Re: Write workload is causing severe slowdown in Production
Date: Fri, 23 Mar 2012 17:55:37 +0530
Message-ID: <00a501cd08f0$11385490$33a8fdb0$@com> (raw)
In-Reply-To: <6df55552430e183a729aa039ff729f06.squirrel@sq.gransy.com>
References: <006301cd07fd$358ebe40$a0ac3ac0$@com>
<4F6AFB5902000025000465C7@gw.wicourts.gov>
<CAHyXU0xyVixmLdiMaD2wUU6DgN2AiXi1_Avm+k7vB49BFYEPPA@mail.gmail.com>
<006c01cd08dd$205af940$6110ebc0$@com>
<6df55552430e183a729aa039ff729f06.squirrel@sq.gransy.com>
> Are those wrapped in a transaction or not? Each transaction forces a fsync
> when committing, and if each of those INSERT/UPDATE statements stands on
> it's own it may cause of lot of I/O.
Yes, it's wrapped inside a transaction. May be this could be a reason for slowdown, as you've highlighted here. Atleast, we've got some guidance here to troubleshoot in this aspect also.
> There are tools that claim to remove the object vs. relational discrepancy
> when accessing the database. They often generate queries on the fly, and
> some of the queries are pretty awful (depends on how well the ORM model is
> defined). There are various reasons why this may suck - loading too much
> data, using lazy fetch everywhere etc.
Thanks for the clarification.
> Are you using something like Hibernate, JPA, ... to handle persistence?
No, we're not using any persistence frameworks/libraries as such.
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To: pgsql-performance@postgresql.org
Cc: gnanam@zoniac.com, tv@fuzzy.cz, mmoncure@gmail.com, kevin.grittner@wicourts.gov
Subject: Re: Write workload is causing severe slowdown in Production
In-Reply-To: <00a501cd08f0$11385490$33a8fdb0$@com>
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