Re: Proposal for CSN based snapshots

On Fri, Jun 7, 2013 at 3:47 PM, Greg Stark <stark(at)mit(dot)edu> wrote:
> On Thu, Jun 6, 2013 at 11:42 PM, Ants Aasma <ants(at)cybertec(dot)at> wrote:
>> To refresh your memory the basic idea is to change visibility
>> determination to be based on a commit sequence number (CSN for short)
>> - a 8 byte number incremented on every commit representing the total
>> ordering of commits
>
> I think we would just use the LSN of the commit record which is
> effectively the same but doesn't require a new counter.
> I don't think this changes anything though.

I briefly touched on that point in the Hot Standby section. This has
some consequences for locking in CommitTransaction, but otherwise LSN
is as good as any other monotonically increasing value.

Regards,
Ants Aasma
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