Excerpts from Heikki Linnakangas's message of dom jun 24 12:22:30 -0400 2012:
> Replace XLogRecPtr struct with a 64-bit integer.
>
> This simplifies code that needs to do arithmetic on XLogRecPtrs.
>
> To avoid changing on-disk format of data pages, the LSN on data pages is
> still stored in the old format. That should keep pg_upgrade happy. However,
> we have XLogRecPtrs embedded in the control file, and in the structs that
> are sent over the replication protocol, so this changes breaks compatibility
> of pg_basebackup and server. I didn't do anything about this in this patch,
> per discussion on -hackers, the right thing to do would to be to change the
> replication protocol to be architecture-independent, so that you could use
> a newer version of pg_receivexlog, for example, against an older server
> version.
One commit in this series broke pg_upgrade, which depended on
pg_resetxlog output: "First log file id after reset".
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Álvaro Herrera <alvherre@commandprompt.com>
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