On 9 December 2014 at 04:21, Andres Freund <and...@2ndquadrant.com> wrote: > On 2014-12-08 14:09:19 -0500, Robert Haas wrote: >> > records, just fpis. There is no evidence that we even want to compress >> > other record types, nor that our compression mechanism is effective at >> > doing so. Simple => keep name as compress_full_page_writes >> >> Quite right. > > I don't really agree with this. There's lots of records which can be > quite big where compression could help a fair bit. Most prominently > HEAP2_MULTI_INSERT + INIT_PAGE. During initial COPY that's the biggest > chunk of WAL. And these are big and repetitive enough that compression > is very likely to be beneficial.
Yes, you're right there. I was forgetting those aren't FPIs. However they are close enough that it wouldn't necessarily effect the naming of a parameter that controls such compression. > I still think that just compressing the whole record if it's above a > certain size is going to be better than compressing individual > parts. I think its OK to think it, but we should measure it. For now then, I remove my objection to a commit of this patch based upon parameter naming/rethinking. We have a fine tradition of changing the names after the release is mostly wrapped, so lets pick a name in a few months time when the dust has settled on what's in. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers