Re: checkpoints taking much longer than expected

On 2019-06-14 16:01:40 +0200, Tiemen Ruiten wrote:
> FS is ZFS, the dataset with the PGDATA directory on it has the following
> properties (only non-default listed):
[...]
> My problem is that checkpoints are taking a long time. Even when I run a few
> manual checkpoints one after the other, they keep taking very long, up to 10
> minutes:

There was a discussion about ZFS' COW behaviour and PostgreSQL reusing
WAL files not being a good combination about a year ago:
https://www.postgresql.org/message-id/flat/CACukRjO7DJvub8e2AijOayj8BfKK3XXBTwu3KKARiTr67M3E3w%40mail.gmail.com

Maybe you have the same problem?

        hp

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   _  | Peter J. Holzer    | we build much bigger, better disasters now
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