Re: max_slot_wal_keep_size and wal_keep_segments

On 7/17/20 5:11 AM, Fujii Masao wrote:
>
>
> On 2020/07/14 20:30, David Steele wrote:
>> On 7/14/20 12:00 AM, Fujii Masao wrote:
>>>
>>> The patch was no longer applied cleanly because of recent commit.
>>> So I updated the patch. Attached.
>>>
>>> Barring any objection, I will commit this patch.
>>
>> This doesn't look right:
>>
>> +   the <xref linkend="guc-wal-keep-size"/> most recent megabytes
>> +   WAL files plus one WAL file are
>>
>> How about:
>>
>> +   <xref linkend="guc-wal-keep-size"/> megabytes of
>> +   WAL files plus one WAL file are
>
> Thanks for the comment! Isn't it better to keep "most recent" part?
> If so, what about either of the followings?
>
> 1. <xref linkend="guc-wal-keep-size"/> megabytes of WAL files plus
>     one WAL file that were most recently generated are kept all time.
>
> 2. <xref linkend="guc-wal-keep-size"/> megabytes + <xref
> linkend="guc-wal-segment-size"> bytes
>     of WAL files that were most recently generated are kept all time.

"most recent" seemed implied to me, but I see your point.

How about:

+ the most recent <xref linkend="guc-wal-keep-size"/> megabytes of
+ WAL files plus one additional WAL file are

Regards,
--
-David
david(at)pgmasters(dot)net