On Oct 13, 2006, at 14:36 , Joshua D. Drake wrote:
> Stephen Frost wrote:
>> * Alexander Staubo (alex@purefiction.net) wrote:
>>> What formula did you use to get to that number? Is there a generic
>>> way on Linux to turn off (controller-based?) write caching?
>>
>> Just a side-note, but if you've got a pretty good expectation that
>> you
>> won't be without power for 24 consecutive hours ever you can get a
>> controller with a battery-backed write cache (some will do better
>> than
>> 24 hours too). For the performance concerned... :)
>
> No to mention if you are *that* concerned you could buy a generator
> for
> 500 bucks that will keep the machine alive if you absolutely have to.
>
> There is nothing wrong with write back cache as long as you have the
> infrastructure to support it.
Why does the battery have to be at that level? It's seems like a
reasonable poor man's solution would be to have a standard $50 UPS
plugged in and have the UPS signal postgresql to shut down and sync.
Then, theoretically, it would be safe to run with fsync=off. The
level of risk seems the same no?
-M