From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ayub Khan <ayub.hp@gmail.com>
cc: Pgsql Performance <pgsql-performance@lists.postgresql.org>
Subject: Re: slow performance with cursor
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Comments: In-reply-to Ayub Khan <ayub.hp@gmail.com>
	message dated "Fri, 25 Jun 2021 19:09:31 +0300"
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Date: Fri, 25 Jun 2021 14:04:21 -0400
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Ayub Khan <ayub.hp@gmail.com> writes:
> Is there any setting which needs to be modified to improve the performance
> of cursors. Also facing slow response with reading blobs (images) from db.
> Not an ideal way for storing images in db but this is a legacy application
> and wanted to check if there a quick tweak which can improve the
> performance while reading blob data from db.

Possibly twiddling cursor_tuple_fraction would help.  The default setting
tends to encourage fast-start plans, which might be counterproductive
if you're always fetching the entire result in one go.

			regards, tom lane