Re: Hard limit on WAL space used (because PANIC sucks)

On 2013-06-06 17:00:30 +0300, Heikki Linnakangas wrote:
> A more workable idea is to sprinkle checks in higher-level code, before you
> hold any critical locks, to check that there is enough preallocated WAL.
> Like, at the beginning of heap_insert, heap_update, etc., and all similar
> indexam entry points. I propose that we maintain a WAL reservation system in
> shared memory.

I am rather doubtful that this won't end up with a bunch of complex code
that won't prevent the situation in all circumstances but which will
provide bugs/performance problems for some time.
Obviously that's just gut feeling since I haven't see the code...

I am much more excited about getting the soft limit case right and then
seeing how many problems remain in reality.

Greetings,

Andres Freund

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