Re: [HACKERS] Remove secondary checkpoint - Mailing list pgsql-hackers

From Michael Paquier
Subject Re: [HACKERS] Remove secondary checkpoint
Date
Msg-id CAB7nPqSMvoWecgjSkcFXXbNbrVuFDkBo08SRMKP2tvWEuACHcA@mail.gmail.com
Whole thread Raw
In response to Re: [HACKERS] Remove secondary checkpoint  ("Tsunakawa, Takayuki" <tsunakawa.takay@jp.fujitsu.com>)
Responses Re: [HACKERS] Remove secondary checkpoint
List pgsql-hackers
On Tue, Oct 24, 2017 at 5:58 PM, Tsunakawa, Takayuki
<tsunakawa.takay@jp.fujitsu.com> wrote:
> If the latest checkpoint record is unreadable (the WAL segment/block/record is corrupt?), recovery from the previous
checkpointwould also stop at the latest checkpoint.  And we don't need to replay the WAL records between the previous
checkpointand the latest one, because their changes are already persisted when the latest checkpoint was taken.  So,
theuser should just do pg_resetxlog and start the database server when the recovery cannot find the latest checkpoint
recordand PANICs? 

Not necessarily. If a failure is detected when reading the last
checkpoint, as you say recovery would begin at the checkpoint prior
that and would stop when reading the record of last checkpoint, still
one could use a recovery.conf with restore_command to fetch segments
from a different source, like a static archive, as only the local
segment may be corrupted.
--
Michael


--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers

pgsql-hackers by date:

Previous
From: "Tsunakawa, Takayuki"
Date:
Subject: Re: [HACKERS] Remove secondary checkpoint
Next
From: "Tsunakawa, Takayuki"
Date:
Subject: Re: [HACKERS] Remove secondary checkpoint