Re: [HACKERS] Creating backup history files for backups taken from standbys

On 19 September 2017 at 00:33, David Steele <david(at)pgmasters(dot)net> wrote:
> On 9/18/17 7:26 PM, Michael Paquier wrote:
>> On Tue, Sep 19, 2017 at 8:14 AM, David Steele <david(at)pgmasters(dot)net> wrote:
>>> On 8/31/17 11:56 PM, Michael Paquier wrote:
>>>> Here is an updated patch with refreshed documentation, as a result of
>>>> 449338c which was discussed in thread
>>>> https://www.postgresql.org/message-id/d4d951b9-89c0-6bc1-b6ff-d0b2dd5a8966@pgmasters.net.
>>>> I am just outlining the fact that a backup history file gets created
>>>> on standbys and that it is archived.
>>>
>>> The patch looks good overall. It applies cleanly and passes all tests.
>>>
>>> One question. Do we want to create this file all the time (as written),
>>> or only when archive_mode = always?
>>>
>>> It appears that CleanupBackupHistory() will immediately remove the
>>> history file when archive_mode != always so it seems useless to write
>>> it. On the other hand the code is a bit simpler this way. Thoughts?
>>
>> With archive_mode = off, the bytes of the backup history file are
>> still written to disk, so my take on the matter is to keep the code
>> simple.
>
> I'm OK with that.

I'm not.

If we want to do this why not only do it in the modes that have meaning?
i.e. put an if() test in for archive_mode == always

Which also makes it a smaller and clearer patch

--
Simon Riggs http://www.2ndQuadrant.com/
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