Re: pg_dump --snapshot - Mailing list pgsql-hackers

From Joe Conway
Subject Re: pg_dump --snapshot
Date
Msg-id 518830A0.7010403@joeconway.com
Whole thread Raw
In response to Re: pg_dump --snapshot  (Stephen Frost <sfrost@snowman.net>)
Responses Re: pg_dump --snapshot  (Craig Ringer <craig@2ndquadrant.com>)
List pgsql-hackers
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On 05/06/2013 03:00 PM, Stephen Frost wrote:
> For example, I'm not sure that we need more information in the
> WAL.. What we need is a way to tell VACUUM to skip over 'recently
> modified' records and not mark them as dead until some time has
> passed.  This is essentially what we're already doing with the
> feedback mechanism in replication, isn't it?  Would it be possible
> to make that a simple timer instead of requiring a replication
> system which is feeding back that information based on queries
> which are running on the replica?

This sounds a lot like having an "idle in transaction" session hanging
around. Could we use something akin to a prepared transaction to
preserve the ability to use the snapshot? Maybe with an (optional)
expiration timestamp?

Joe


- -- 
Joe Conway
credativ LLC: http://www.credativ.us
Linux, PostgreSQL, and general Open Source
Training, Service, Consulting, & 24x7 Support
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