Subject: Re: A failure of standby to follow timeline switch
To: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Cc: pgsql-hackers@lists.postgresql.org
References: <a8bc5939-1c88-e35c-166a-6ef07f06dd83@oss.nttdata.com>
 <20210104.120610.767727791822348683.horikyota.ntt@gmail.com>
 <ac594c30-9907-343a-4111-796678b66d31@oss.nttdata.com>
 <20210105.172602.1507192651696938626.horikyota.ntt@gmail.com>
From: Fujii Masao <masao.fujii@oss.nttdata.com>
Message-ID: <e0b35dd8-90f3-b02a-9b6d-c6700080fd90@oss.nttdata.com>
Date: Thu, 7 Jan 2021 11:55:33 +0900
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On 2021/01/05 17:26, Kyotaro Horiguchi wrote:
> At Mon, 4 Jan 2021 19:00:21 +0900, Fujii Masao <masao.fujii@oss.nttdata.com> wrote in
>>
>>
>> On 2021/01/04 12:06, Kyotaro Horiguchi wrote:
>>> At Sat, 26 Dec 2020 02:15:06 +0900, Fujii Masao
>>> <masao.fujii@oss.nttdata.com> wrote in
>>>>
>>>> On 2020/12/25 12:03, Kyotaro Horiguchi wrote:
>>> The attached is the fixed version.
>>
>> Thanks for updating the patches!
>>
>>> In the first patch, the test added to 001_stream_rep.pl involves two
>>> copied functions related to server-log investigation from
>>> 019_repslot_limit.pl.
>>
>> So you're planning to define them commonly in TestLib.pm or elsewhere?
> 
> Yeah.. That's correct. Newly added as the first patch.
> 
> While making that change, I extended the interface of slurp_file to
> allow reading from arbitrary position.

Is this extension really helpful for current use case?
At least I'd like to avoid back-patching this since it's an exntesion...

  		OsFHandleOpen(my $fh = IO::Handle->new(), $fHandle, 'r')
  		  or croak "could not read \"$filename\": $^E\n";
+		seek($fh, $from, 0)
+		  or croak "could not seek \"$filename\" to $from: $^E\n";

I'm not familiar with this area, but SetFilePointer() is more suitable
rather than seek()?


> Thanks. The attached is the revised patchset.

Thanks!

Regards,

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