>> There are actually no "real" data changes being made on your master
>> for some reason. So every time archive_timeout is reached a log full
>> of no changes is shipped to your slave and applied - and no checkpoint
>> times are changed for reasons I mentioned above.
>>
>>
>
> thanks, but we have not set archive_timeout, and we have a lot of real
> data changes.
>
> That's why i don't understand why checkpoint never happen on the slave.
>
What about the other values in pg_controldata output, do they change at
all? If they remain constant, maybe the logs are just not applied. Also,
are there any "restored log file xxx from archive" entries in postgres
log?
regards,
Martin