Thread: What happens if checkpoint haven't completed until the nextcheckpoint interval or max_wal_size?
What happens if checkpoint haven't completed until the nextcheckpoint interval or max_wal_size?
From
Mohammad Sherafat
Date:
In the name of god! Hi, What happens if checkpoint haven't completed until the next checkpoint interval or max_wal_size? thanks, regards, Mohammad Sherafat.
Re: What happens if checkpoint haven't completed until the nextcheckpoint interval or max_wal_size?
From
Laurenz Albe
Date:
Mohammad Sherafat wrote: > In the name of god! It is not considered good style to hurt people's religious feelings by using the name of god in vain. > What happens if checkpoint haven't completed until the next checkpoint > interval or max_wal_size? Then you have two checkpoints active at the same time. Yours, Laurenz Albe
Re: What happens if checkpoint haven't completed until the nextcheckpoint interval or max_wal_size?
From
Robert Haas
Date:
On Mon, Feb 4, 2019 at 2:50 PM Laurenz Albe <laurenz.albe@cybertec.at> wrote:
Mohammad Sherafat wrote:
> In the name of god!
It is not considered good style to hurt people's religious feelings
by using the name of god in vain.
I agree but...
> What happens if checkpoint haven't completed until the next checkpoint
> interval or max_wal_size?
Then you have two checkpoints active at the same time.
...not about this part. I think the next checkpoint just doesn't start until the one already in progress completes.
...Robert
Re: What happens if checkpoint haven't completed until the nextcheckpoint interval or max_wal_size?
From
Michael Paquier
Date:
On Tue, Feb 05, 2019 at 04:11:55PM +0530, Robert Haas wrote: > ...not about this part. I think the next checkpoint just doesn't start > until the one already in progress completes. Yes, the requests are communicated from any backends to the checkpointer with shared memory (see ckpt_flags in RequestCheckpoint), and the backend signals the checkpointer to do the work, still it won't do the work until the checkpoint currently running finishes. -- Michael
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Re: What happens if checkpoint haven't completed until the nextcheckpoint interval or max_wal_size?
From
Kyotaro HORIGUCHI
Date:
At Tue, 5 Feb 2019 20:42:59 +0900, Michael Paquier <michael@paquier.xyz> wrote in <20190205114259.GH1882@paquier.xyz> > On Tue, Feb 05, 2019 at 04:11:55PM +0530, Robert Haas wrote: > > ...not about this part. I think the next checkpoint just doesn't start > > until the one already in progress completes. > > Yes, the requests are communicated from any backends to the > checkpointer with shared memory (see ckpt_flags in RequestCheckpoint), > and the backend signals the checkpointer to do the work, still it > won't do the work until the checkpoint currently running finishes. And, requests for checkpoints are not queued. Multiple checkpoint requests (both automatically and manually) made during a checkpoint are finished at once at the end of the running checkpoint. regards. -- Kyotaro Horiguchi NTT Open Source Software Center