On Fri, 2 Jul 2021 at 00:19, Simon Riggs <simon.ri...@enterprisedb.com> wrote:
> > So yeah. I think it'd be better to log the info you want at start-of-txn > unless there's a compelling reason not so, and I don't see one yet. > > AFAIK, XLOG_XACT_ASSIGNMENT does not occur for normal top-level > transactions, only for subxids. > > I don't really want to add an extra record just for this because it > will slow down applications and it won't get turned on as often. > OK, that makes sense - I was indeed operating on an incorrect assumption. I wouldn't want to add a new record either. I thought we could piggyback on XLOG_XACT_ASSIGNMENT with a new chunk that's only added when the feature is required, much like we do for replication origin info on commit records. Is it worth considering forcing XLOG_XACT_ASSIGNMENT to be logged if this feature is enabled? If you don't think the sorts of use cases I presented are worth the trouble that's fair enough. I'm not against adding it on the commit record. It's just that with logical decoding moving toward a streaming model I suspect only having it at commit time may cause us some pain later.
