| From: | Andres Freund <andres(at)anarazel(dot)de> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>, Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com>, Magnus Hagander <magnus(at)hagander(dot)net>, Michael Paquier <michael(at)paquier(dot)xyz>, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>, David Fetter <david(at)fetter(dot)org>, PostgreSQL Development <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Bump default wal_level to logical |
| Date: | 2020-06-08 21:32:15 |
| Message-ID: | 20200608213215.mgk3cctlzvfuaqm6@alap3.anarazel.de |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Hi,
On 2020-06-08 13:27:50 -0400, Tom Lane wrote:
> If we can allow wal_level to be changed on the fly, I agree that would
> help reduce the pressure to make the default setting more expensive.
> I don't recall why it's PGC_POSTMASTER right now, but I suppose there
> was a reason for that ...
There's reasons, but IIRC they're all solvable with reasonable effort. I
think most of it boils down to only being able to rely on the new
wal_level after a while. For minimal->recovery we basically need a
checkpoint started after the change in configuration, and for
recovery->logical we need to wait until all sessions have a) read the
new config setting b) finished the transaction that used the old
setting.
Greetings,
Andres Freund
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Andres Freund | 2020-06-08 22:02:40 | Re: valgrind versus pg_atomic_init() |
| Previous Message | Justin Pryzby | 2020-06-08 21:29:57 | Re: proposal: possibility to read dumped table's name from file |