Re: Disable WAL backup pages when fsync is off - Mailing list pgsql-patches

Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > The following patch disables WAL backup pages when fsync is off.
>
> This is a good idea why?

There is no need to write backup pages if fsync is off.  Our TODO has:

    * Turn off after-change writes if fsync is disabled

      If fsync is off, there is no purpose in writing full pages to WAL

Basically, with fsync off, you are saying you don't care about crash
recovery, so why write those pages?

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