Re: PostgreSQL 64 Bit XIDs - Transaction IDs

On 23.03.2012 06:45, Gerhard Wiesinger wrote:

> With a database admin of a commercial database system I've discussed
> that they have to provide and they also achieve 2^31 transactions per
> SECOND!
> As PostgreSQL uses transaction IDs (XIDs) in the range of 2^31 they
> would turn around in about one second.

Wow. What application issues that much transactions? And what is the
database system that can handle that? I can't think of a single machine
capable of this - and hardy believe postgresql can came close. 2^31
transactions mean that a single one lasts 0.5ns. Even the fastest
DDR3-2133 has cycle times of 4ns.

I have seen a database monster in action - 43 trillion (academic)
transactions per day, but that's only 5*10^8 transactions per second,
under a quarter of 2^31 per second.

So, I can't answer your question - but you triggered my curiosity :-)

Cheers,
Jan