Tom Lane wrote: > Zdenek Kotala <[EMAIL PROTECTED]> writes: >> Koichi Suzuki wrote: >>> I've once proposed a patch for 64bit transaction ID, but this causes >>> some overhead to each tuple (XMIN and XMAX). > >> Did you check performance on 32-bit or 64-bit systems and 64-bit binary >> version of PGSQL? I think that today is not problem to have 64-bit >> architecture and 64-bit ID should increase scalability of Postgres.
I checked the performance on 64-bit system and 64bit binary. > > The percentage increase in I/O demand is the main reason the patch was > rejected, not so much the arithmetic. That's right. I've also ovserved I/O demand increase. I remember we have to pay three to five percent performance decrease in pgbench. So I don't think we should apply this patch without further justification. I'm looking for other reasons for larger transaction ID. > > regards, tom lane > > ---------------------------(end of broadcast)--------------------------- > TIP 4: Have you searched our list archives? > > http://archives.postgresql.org > -- Koichi Suzuki ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend