Thread: maximum amount of data to be written during checkpoint?

hi,
what is the maximum amount of data to be written in checkpoint?

i always assumed this to be <shared_buffers>.

but some last tests show it to be much more. what am i missing?

best regards,

depesz

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On Thu, 2008-01-24 at 11:21 +0100, hubert depesz lubaczewski wrote:

> what is the maximum amount of data to be written in checkpoint?
>
> i always assumed this to be <shared_buffers>.
>
> but some last tests show it to be much more. what am i missing?

Fsync will flush all outstanding writes, so you probably have some
writes that weren't yet flushed before the checkpoint started. If you
don't do any intermediate writing then this could be *all* of the data
you've written since the last checkpoint. If you want to reduce this,
set parameters to perform more regular writes from filesystem to disk.

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  Simon Riggs
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