> 8 июня 2017 г., в 17:03, Amit Kapila <amit.kapil...@gmail.com> написал(а):
> On Thu, Jun 8, 2017 at 6:49 PM, Dmitriy Sarafannikov
> <dsarafanni...@yandex.ru> wrote:
>>> Why didn't rsync made the copies on master and replica same?
>> Because rsync was running with —size-only flag.
> IIUC the situation, the new WAL and updated pg_control file has been
> copied, but not updated data files due to which the WAL has not been
> replayed on replicas?  If so, why the pg_control file is copied, it's
> size shouldn't have changed?

Because on master pg_upgrade moves $prefix/9.5/data/global/pg_control to 
$prefix/9.5/data/global/pg_control.old and creates new 
$prefix/9.6/data/global/pg_control without making hardlink. When running rsync 
from master to replica rsync sees $prefix/9.6/data/global/pg_control on master 
and checks if it is a hardlink. Since it is not a hardlink and 
$prefix/9.6/data/global/pg_control does not exist on replica rsync copies it. 
For data files the logic is different since they are hardlinks, corresponding 
files exist on replica and they are the same size.

> -- 
> With Regards,
> Amit Kapila.
> EnterpriseDB: http://www.enterprisedb.com

May the force be with you…

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