Re: fsync and hardware write cache

pgsql@mohawksoft.com wrote:
> Something to think about:
> 
> if you run PostgreSQL with fsync on, but you use the hardware write cache
> on your disk drives, how likely are you to lose data? Obviously, this is a
> fairly limited problem, as it only applies to power down (which you can
> control) or power loss where the risks may be reduced but not eliminated
> with a UPS.
> 
> Does it make sense to add a platform specific call that will flush a write
> cache when fsync is enable?

We have discussed this in the past and just require hardware to honor
the operating system fsync.  If it doesn't honor that, how do we fix it
other than telling them to properly configure their hardware.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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