Обсуждение: Is it possible to change wal_level online
Hi,
restart, I'm not familiar with this stuff so far and I didn't get any good
information from searching the email archive. So I want to gather
some feedbacks from experts to see if it is possible and if not, why
it would be the key blocker for this. Basically I agree that changing
the wal_level online will be a good experience for users.
Best Regards
Andy Fan
On Thu, Sep 14, 2023, at 7:05 AM, Andy Fan wrote:
Currently it is complained that wal_level changes require an instancerestart, I'm not familiar with this stuff so far and I didn't get any goodinformation from searching the email archive. So I want to gathersome feedbacks from experts to see if it is possible and if not, whyit would be the key blocker for this. Basically I agree that changingthe wal_level online will be a good experience for users.
This topic was already discussed. See this thread [1] that was requesting to
change the wal_level default value. There might be other threads but I didn't
try hard to find them.
On Thu, Sep 14, 2023 at 9:22 PM Euler Taveira <euler@eulerto.com> wrote:
On Thu, Sep 14, 2023, at 7:05 AM, Andy Fan wrote:Currently it is complained that wal_level changes require an instancerestart, I'm not familiar with this stuff so far and I didn't get any goodinformation from searching the email archive. So I want to gathersome feedbacks from experts to see if it is possible and if not, whyit would be the key blocker for this. Basically I agree that changingthe wal_level online will be a good experience for users.This topic was already discussed. See this thread [1] that was requesting tochange the wal_level default value. There might be other threads but I didn'ttry hard to find them.
Thank you Euler, this one is already the best one I ever found.
Best Regards
Andy Fan
Hi, On September 14, 2023 6:21:59 AM PDT, Euler Taveira <euler@eulerto.com> wrote: >On Thu, Sep 14, 2023, at 7:05 AM, Andy Fan wrote: >> Currently it is complained that wal_level changes require an instance >> restart, I'm not familiar with this stuff so far and I didn't get any good >> information from searching the email archive. So I want to gather >> some feedbacks from experts to see if it is possible and if not, why >> it would be the key blocker for this. Basically I agree that changing >> the wal_level online will be a good experience for users. >> > >This topic was already discussed. See this thread [1] that was requesting to >change the wal_level default value. There might be other threads but I didn't >try hard to find them. > > >[1] https://www.postgresql.org/message-id/20200608213215.mgk3cctlzvfuaqm6%40alap3.anarazel.de I think it's gotten a bit easier since then, because we now have global barriers, to implement the waiting that's mentionedin the email. Possibly we should do the switch to logical dynamically, without a dedicated wal_level. Whenever a logical slot exists, automaticallyincrease the Wal level, whenever the last slot is dropped, lower it again. Plus some waiting to ensure everybackend has knows about the new value. Regards, Andres -- Sent from my Android device with K-9 Mail. Please excuse my brevity.