Re: [patch] Fix checksum verification in base backups for zero page headers - Mailing list pgsql-hackers

From Anastasia Lubennikova
Subject Re: [patch] Fix checksum verification in base backups for zero page headers
Date
Msg-id 9489c221-e2ef-e7ad-d921-5ccad71b14de@postgrespro.ru
Whole thread Raw
In response to Re: [patch] Fix checksum verification in base backups for zero page headers  (Michael Banck <michael.banck@credativ.de>)
Responses Re: [patch] Fix checksum verification in base backups for zero page headers  (Michael Banck <michael.banck@credativ.de>)
List pgsql-hackers
On 22.09.2020 17:30, Michael Banck wrote:
> Hi,
>
> Am Dienstag, den 22.09.2020, 16:26 +0200 schrieb Michael Banck:
>> Am Mittwoch, den 02.09.2020, 16:50 +0300 schrieb Anastasia Lubennikova:
>>> I've looked through the previous discussion. As far as I got it, most of
>>> the controversy was about online checksums improvements.
>>>
>>> The warning about pd_upper inconsistency that you've added is a good
>>> addition. The patch is a bit messy, though, because a huge code block
>>> was shifted.
>>>
>>> Will it be different, if you just leave
>>>       "if (!PageIsNew(page) && PageGetLSN(page) < startptr)"
>>> block as it was, and add
>>>       "else if (PageIsNew(page) && !PageIsZero(page))" ?
>> Thanks, that does indeed look better as a patch and I think it's fine
>> as-is for the code as well, I've attached a v2.
> Sorry, forgot to add you as reviewer in the proposed commit message,
> I've fixed that up now in V3.
>
>
> Michael
>
Great. This version looks good to me.
Thank you for answering my questions, I agree, that we can work on them 
in separate threads.

So I mark this one as ReadyForCommitter.

The only minor problem is a typo (?) in the proposed commit message.
"If a page is all zero, consider that a checksum failure." It should be 
"If a page is NOT all zero...".

-- 
Anastasia Lubennikova
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company




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