Re: Design proposal: fsync absorb linear slider

On Mon, Jul 22, 2013 at 11:48 PM, Greg Smith <greg@2ndquadrant.com> wrote:
> Recently I've been dismissing a lot of suggested changes to checkpoint fsync
> timing without suggesting an alternative.  I have a simple one in mind that
> captures the biggest problem I see:  that the number of backend and
> checkpoint writes to a file are not connected at all.
>
> We know that a 1GB relation segment can take a really long time to write
> out.  That could include up to 128 changed 8K pages, and we allow all of
> them to get dirty before any are forced to disk with fsync.

By my count, it can include up to 131,072 changed 8K pages.

-- 
Robert Haas
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