Re: HOT is applied - Mailing list pgsql-hackers

From Pavan Deolasee
Subject Re: HOT is applied
Date
Msg-id 2e78013d0709210119p360f94d0y26c0986e969ec479@mail.gmail.com
Whole thread Raw
In response to Re: HOT is applied  (Bruce Momjian <bruce@momjian.us>)
List pgsql-hackers


On 9/21/07, Bruce Momjian <bruce@momjian.us> wrote:

This might be a simplistic question but if the page is +90% full and
there is a long-lived transaction, isn't Postgres going to try pruning
on each page read access?


The way it stands today, yes. Thats one reason why we are seeing
the performance drop in this particular case.

I liked the earlier proposed idea of storing the xid in the page header
to quickly tell us whether its worth pruning the page.

Thanks,
Pavan

--
Pavan Deolasee
EnterpriseDB     http://www.enterprisedb.com

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