Re: 9.3: load path to mitigate load penalty for checksums - Mailing list pgsql-hackers

From Tom Lane
Subject Re: 9.3: load path to mitigate load penalty for checksums
Date
Msg-id 18085.1339517520@sss.pgh.pa.us
Whole thread Raw
In response to Re: 9.3: load path to mitigate load penalty for checksums  (Merlin Moncure <mmoncure@gmail.com>)
Responses Re: 9.3: load path to mitigate load penalty for checksums  ("Kevin Grittner" <Kevin.Grittner@wicourts.gov>)
Re: 9.3: load path to mitigate load penalty for checksums  (Merlin Moncure <mmoncure@gmail.com>)
List pgsql-hackers
Merlin Moncure <mmoncure@gmail.com> writes:
> On Tue, Jun 12, 2012 at 7:42 AM, Robert Haas <robertmhaas@gmail.com> wrote:
>> Instead of trying to maintain MVCC semantics, maybe we should just
>> have something like COPY (FROZEN) that just writes frozen tuples into
>> the table and throws MVCC out the window. �Seems like that would be a
>> lot easier to implement and satisfy basically the same use cases.

> -1: The situation with hint bit i/o patterns on many workloads is
> untenable but it's not safe to assume MVCC can be ditched in those
> workloads.  Also, COPY does nothing about deletes.  Neither does the
> proposal as stated but I think it's easier to generalize into 'I want
> to put hint bits in now so I don't have to deal with them later'.

Dunno, I think Robert's idea has a fair amount of merit: mainly because
it will probably satisfy 90% of use cases for 1% of the work.
        regards, tom lane


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