Re: crash-safe visibility map, take four

On Wed, Mar 23, 2011 at 2:16 AM, Jesper Krogh <jesper(at)krogh(dot)cc> wrote:
> On 2011-03-22 21:43, Robert Haas wrote:
>>
>> I took a crack at implementing the first approach described above,
>> which seems to be by far the simplest idea we've come up with to date.
>>  Patch attached.  It doesn't seem to be that complicated, which could
>> mean either that it's not that complicated or that I'm missing
>> something.  Feel free to point and snicker in the latter case.
>
> Looks simple, but there is now benefit on the usage side in the patch,
> so it isn't really "testable" yet? I would love to spend some time testing
> when its doable (even with rough corners.)

What it probably needs right now is some crash testing - insert a
database panic at various points in the code and then check whether
the state after recovery is still OK. Also some code review from
people who understand recovery better than me. *waves to Heikki*

There's a lot more work that will have to be done before this starts
to produce user-visible performance benefits, and then a lot more work
after that before we've exhausted all the possibilities. I can't cope
with all that right now. This is basic infrastructure, that will
eventually enable a variety of cool stuff, but isn't particularly sexy
by itself.

--
Robert Haas
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