Re: transaction wraparound

Am 31.10.19 um 08:15 schrieb Павел Ерёмин:
> Hi.
> I apologize for my English.
> I have a question about transaction wraparound. As far as I know, 
> transaction numbers are 32 bit, which greatly limits their number. In 
> the tuple header there are now  t_xmin and  t_xmax fields - both 32 
> bits each. So why not replace them with a single field with a 
> transaction number of 64 bits length - this is the transaction number 
> that created the version ( this is exactly what the MS SQL server 
> does)? In this case, you do not have to lengthen header tuple. Of 
> course, this can result in increased I/O, so to compensate for it, you 
> can turn off buffered read (O_DIRECT) while reading.

and how to handle deleted/updated tuple?


Regards, Andreas

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