Re: Allow some recovery parameters to be changed with reload

On 2020/11/07 6:36, Sergei Kornilov wrote:
> Hello
> 
>> I'm wondering if it's safe to allow restore_command to be emptied during
>> archive recovery. Even when it's emptied, archive recovery can proceed
>> by reading WAL files from pg_wal directory. This is the same behavior as
>> when restore_command is set to, e.g., /bin/false.
> 
> I am always confused by this implementation detail. restore_command fails? Fine, let's just read file from pg_wal.
Butthis is different topic...
 
> 
> I do not know the history of this fatal ereport. It looks like "must specify restore_command when standby mode is not
enabled"check is only intended to protect the user from misconfiguration and the rest code will treat empty
restore_commandcorrectly, just like /bin/false.
 

Maybe.

Anyway, for now I think that your first patch would be enough, i.e.,
just change the context of restore_command to PGC_SIGHUP.

Regards,

-- 
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION