Horton

Re: ERROR: invalid spinlock number: 0

Fujii Masao <masao.fujii@oss.nttdata.com>

View thread View on postgr.es
From: Fujii Masao <masao.fujii@oss.nttdata.com>
To: Michael Paquier <michael@paquier.xyz>
Cc: pgsql-hackers@postgresql.org
Date: 2021-02-11T14:30:13Z
Lists: pgsql-hackers

Attachments


On 2021/02/11 21:55, Michael Paquier wrote:
> Hi Fujii-san,
> 
> On Tue, Feb 09, 2021 at 11:17:04PM +0900, Fujii Masao wrote:
>> ISTM that the commit 2c8dd05d6c caused this issue. The commit changed
>> pg_stat_get_wal_receiver() so that it reads "writtenUpto" by using
>> pg_atomic_read_u64(). But since "writtenUpto" is initialized only when
>> walreceiver starts up, reading "writtenUpto" before the startup of
>> walreceiver can cause the error.
> 
> Indeed, that's a problem.  We should at least move that out of the
> spin lock area.

Yes, so what about the attached patch?

We didn't notice this issue long time because no regression test checks
pg_stat_wal_receiver. So I included such test in the patch.

Regards,

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

Commits

  1. Fix "invalid spinlock number: 0" error in pg_stat_wal_receiver.

  2. Display the time when the process started waiting for the lock, in pg_locks, take 2

  3. Display the time when the process started waiting for the lock, in pg_locks.

  4. Make pg_stat_wal_receiver consistent with the WAL receiver's shmem info