On Mon, Nov 10, 2014 at 8:40 AM, Alvaro Herrera
<alvherre@2ndquadrant.com> wrote:
> Ah, right. So AFAIK we don't need to keep anything older than
> RecentXmin or something like that -- which is not too old. If I recall
> correctly Josh Berkus was saying in a thread about pg_multixact that it
> used about 128kB or so in <= 9.2 for his customers; that one was also
> limited to RecentXmin AFAIR. I think a similar volume of commit_ts data
> would be pretty acceptable. Moreso considering that it's turned off by
> default.
I'm not sure whether keeping it just back to RecentXmin will be enough
for everybody's needs. But we certainly don't need to keep the last
2^32 records as someone-or-other was suggesting.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company