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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Robert Haas <robertmhaas@gmail.com>,
 Thomas Munro <thomas.munro@gmail.com>,
        Alvaro Herrera <alvherre@2ndquadrant.com>,
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        Peter Geoghegan <pg@bowt.ie>, Bruce Momjian <bruce@momjian.us>,
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Subject: Re: Improving connection scalability: GetSnapshotData()
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
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Andres Freund <andres@anarazel.de> writes:
> For the first, one issue is that there's no obviously good candidate for
> an uninitialized xid. We could use something like FrozenTransactionId,
> which may never be in the procarray. But it's not exactly pretty.

Huh?  What's wrong with using InvalidTransactionId?

			regards, tom lane