On 09/11/2014 03:16 PM, George Neuner wrote:
>
> If the driver permits it and you [or your users] can be trusted to
> perform a safe unmount via the OS *before* disconnecting the device,
> then you can enable write caching for the device using the device
> manager. [Note that the device must be connected for it to be visible
> in the device manager.]
It shouldn't be living dangerously, actually.
While I haven't tested it myself, writeback caching on the external
drive should be safe so long as it continues to honour explicit disk
flush requests.
That's why we have the WAL and do periodic checkpoints. If you yank the
drive mid-write you'll lose uncommitted transactions and might have
slower startup next time around, but it should otherwise not be overly
problematic.
--
Craig Ringer http://www.2ndQuadrant.com/
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