Skip site navigation (1) Skip section navigation (2)

Re: Replication Syatem

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: "Pavan Deolasee" <pavan(dot)deolasee(at)gmail(dot)com>
Cc: "Gauri Kanekar" <meetgaurikanekar(at)gmail(dot)com>, "Shane Ambler" <pgsql(at)sheeky(dot)biz>, "Alvaro Herrera" <alvherre(at)commandprompt(dot)com>, "Greg Smith" <gsmith(at)gregsmith(dot)com>, pgsql-performance(at)postgresql(dot)org
Subject: Re: Replication Syatem
Date: 2008-04-30 14:46:28
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-performance
"Pavan Deolasee" <pavan(dot)deolasee(at)gmail(dot)com> writes:
> That's weird. With that fillfactor, you should have a very high
> percentage of HOT update ratio. It could be a very special case that
> we might be looking at.

He's testing

>> update table1 set delta1 = 100 where code/1000000 =999;

so all the rows being updated fall into a contiguous range of "code"
values.  If the table was loaded in such a way that those rows were
also physically contiguous, then the updates would be localized and
would very soon run out of freespace on those pages.

			regards, tom lane

In response to


pgsql-performance by date

Next:From: Tom LaneDate: 2008-04-30 15:02:39
Subject: Re: Replication Syatem
Previous:From: Tom LaneDate: 2008-04-30 14:43:11
Subject: Re: Understanding histograms

Privacy Policy | About PostgreSQL
Copyright © 1996-2017 The PostgreSQL Global Development Group