Horton

Re: [HACKERS] getting rid of SnapshotNow

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Alvaro Herrera <alvherre@2ndquadrant.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Noah Misch <noah@leadboat.com>, pgsql-hackers@postgresql.org, pgsql-odbc@postgresql.org
Date: 2013-07-22T20:23:14Z
Lists: pgsql-hackers 
On Fri, Jul 19, 2013 at 1:20 PM, Alvaro Herrera
<alvherre@2ndquadrant.com> wrote:
>> 4. If we use GetActiveSnapshot, all the comments about about a fresh
>> MVCC snapshot still apply.  However, the snapshot in question could be
>> even more stale, especially in repeatable read or serializable mode.
>> However, this might be thought a more consistent behavior than what we
>> have now.  And I'm guessing that this function is typically run as its
>> own transaction, so in practice this doesn't seem much different from
>> an MVCC snapshot, only cheaper.
>>
>> At the moment, I dislike #2 and slightly prefer #4 to #3.
>
> +1 for #4, and if we ever need more then we can provide a non-default
> way to get at #2.

OK, done.

-- 
Robert Haas
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