Re: Load Distributed Checkpoints, final patch

Heikki Linnakangas wrote:
> For comparison, imola-328 has full_page_writes=off. Checkpoints last ~9
> minutes there, and the graphs look very smooth. That suggests that
> spreading the writes over a longer time wouldn't make a difference, but
> smoothing the rush at the beginning of checkpoint might. I'm going to
> try the algorithm I posted, that uses the WAL consumption rate from
> previous checkpoint interval in the calculations.

One thing that concerns me is that checkpoint smoothing happening just
after the checkpoint is causing I/O at the same time that
full_page_writes is causing additional I/O. Ideally we would do the
smoothing toward the end of the checkpoint cycle, but I realize that has
problems of its own.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://www.enterprisedb.com

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