Re: Usage of epoch in txid_current - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Usage of epoch in txid_current
Date
Msg-id 14670.1512500136@sss.pgh.pa.us
Whole thread Raw
In response to Re: Usage of epoch in txid_current  (Stephen Frost <sfrost@snowman.net>)
List pgsql-hackers
Stephen Frost <sfrost@snowman.net> writes:
> * Andres Freund (andres@anarazel.de) wrote:
>> I kinda wonder if we shouldn't just track nextXid as a 64bit integer
>> internally, instead of bothering with tracking the epoch
>> separately. Then we can "just" truncate it in the cases where it's
>> stored in space constrained places etc.

> This sounds reasonable to me, at least, but I've not been in these
> depths much.

+1 ... I think the reason it's like that is simply that nobody's revisited
the XID generator since we decided to require 64-bit integer support.

We'd need this for support of true 64-bit XIDs, too, though I'm unsure
whether that project is going anywhere anytime soon.  In any case it
seems like a separable subset of that work.

            regards, tom lane


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