Re: Artificially increase TransactionID?

Works perfectly. I did need to artificially create pg_clog segments.

Tom: Thanks for the quick response.....

Bob.


On Oct 10, 2007, at 8:46 PM, Tom Lane wrote:

> "Robert A. Klahn" <robert@kint.org> writes:
>> I am interested in increasing the PostgreSQL TransactionID, as part
>> of testing a (yet another) replication system that I am working on.
>> (http://bruce.codehaus.org/ for the interested). I would like to test
>> what happens when the transactionID crosses 2^31 and when it wraps
>> around at 2^32-1. Other than running "select now()" 2^31 times, is
>> there a practical way to raise the transactionID by large amounts?
>
> Shut down postmaster, use pg_resetxlog to set NextXID to whatever you
> want, restart and test.  You might need to artificially create pg_clog
> and pg_subtrans segments matching the chosen starting point, but other
> than that there's not a lot of memory of latest XID in the system.
>
> Bumping it by more than 2G-less-reasonable-safety-margin is unfair of
> course ...
>
>             regards, tom lane