Subject: Re: backup manifests
To: Andres Freund <andres@anarazel.de>, Robert Haas <robertmhaas@gmail.com>
Cc: Noah Misch <noah@leadboat.com>, Stephen Frost <sfrost@snowman.net>,
 Amit Kapila <amit.kapila16@gmail.com>,
 Suraj Kharage <suraj.kharage@enterprisedb.com>,
 tushar <tushar.ahuja@enterprisedb.com>,
 Rajkumar Raghuwanshi <rajkumar.raghuwanshi@enterprisedb.com>,
 Rushabh Lathia <rushabh.lathia@gmail.com>,
 Tels <nospam-pg-abuse@bloodgate.com>,
 Andrew Dunstan <andrew.dunstan@2ndquadrant.com>,
 PostgreSQL Hackers <pgsql-hackers@postgresql.org>,
 Jeevan Chalke <jeevan.chalke@enterprisedb.com>,
 vignesh C <vignesh21@gmail.com>
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From: David Steele <david@pgmasters.net>
Message-ID: <ddbb128b-86e5-7ffb-b5dc-15a414dfde0e@pgmasters.net>
Date: Sun, 29 Mar 2020 21:23:06 -0400
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On 3/29/20 9:07 PM, Andres Freund wrote:
> On 2020-03-29 20:42:35 -0400, Robert Haas wrote:
>>> What do you think of having the verification process also call pg_waldump to
>>> validate the WAL CRCs (shown upthread)?  That looked helpful and simple.
>>
>> I don't love calls to external binaries, but I think the thing that
>> really bothers me is that pg_waldump is practically bound to terminate
>> with an error, because the last WAL segment will end with a partial
>> record.
> 
> I don't think that's the case here. You should know the last required
> record, which should allow to specify the precise end for pg_waldump. If
> it errors out reading to that point, we'd be in trouble.

Exactly. All WAL generated during the backup should read fine with 
pg_waldump or there is a problem.

-- 
-David
david@pgmasters.net