Reply-To: <gnanam@zoniac.com>
From: "Gnanakumar" <gnanam@zoniac.com>
To: "'Tomas Vondra'" <tv@fuzzy.cz>
Cc: "'Merlin Moncure'" <mmoncure@gmail.com>,
	"'Kevin Grittner'" <kevin.grittner@wicourts.gov>,
	<pgsql-performance@postgresql.org>
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	<4F6AFB5902000025000465C7@gw.wicourts.gov>
	<CAHyXU0xyVixmLdiMaD2wUU6DgN2AiXi1_Avm+k7vB49BFYEPPA@mail.gmail.com>
	<006c01cd08dd$205af940$6110ebc0$@com>
	<6df55552430e183a729aa039ff729f06.squirrel@sq.gransy.com>
In-Reply-To: <6df55552430e183a729aa039ff729f06.squirrel@sq.gransy.com>
Subject: Re: Write workload is causing severe slowdown in Production
Date: Fri, 23 Mar 2012 17:55:37 +0530
Organization: Zoniac Software Private Limited
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> 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.