Message-ID: <fa0f1057-923e-ad61-e6f4-ba5fc29135ec@oss.nttdata.com>
Date: Wed, 6 Jul 2022 23:27:58 +0900
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Subject: Re: Backup command and functions can cause assertion failure and
 segmentation fault
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To: Michael Paquier <michael@paquier.xyz>
Cc: Masahiko Sawada <sawada.mshk@gmail.com>,
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 <Yr6XJg2QDT1aHYyJ@paquier.xyz>
From: Fujii Masao <masao.fujii@oss.nttdata.com>
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On 2022/07/01 15:41, Michael Paquier wrote:
> On Fri, Jul 01, 2022 at 03:32:50PM +0900, Fujii Masao wrote:
>> Sounds good idea to me. I updated the patch in that way. Attached.
> 
> Skimming quickly through the thread, this failure requires a
> termination of a backend running BASE_BACKUP.  This is basically
> something done by the TAP test added in 0475a97f with a WAL sender
> killed, and MAX_RATE being used to make sure that we have enough time
> to kill the WAL sender even on fast machines.  So you could add a
> regression test, no?

For the test, BASE_BACKUP needs to be canceled after it finishes do_pg_backup_start(), i.e., checkpointing, and before it calls do_pg_backup_stop(). So the timing to cancel that seems more severe than the test added in 0475a97f. I'm afraid that some tests can easily cancel the BASE_BACKUP while it's performing a checkpoint in do_pg_backup_start(). So for now I'm thinking to avoid such an unstable test.

Regards,

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