Re: Power outage borked things (8.1.10)...

Michael Monnerie wrote:
> On Mittwoch, 20. Februar 2008 Tom Lane wrote:
>> 5. Figure out why a simple power failure was able to do this to you,
>> and fix it. The most likely bet is that your disk drives are lying
>> about write completion ... see the PG archives for discussion.
>
> It could be a caching RAID controller without battery backup unit.
> Nothing help you in a power failure then, except a good backup.
> Had this with a customer - no more filesystem after reboot...

I hardly understand why such things still happen today. It's one of the
most important admin tasks to make sure fsync / fua behave as they should.

Wouldn't it be a good idea to add a chapter to the installation docs?

They cover SHM settings and vm.overcommit -- why not a short
introduction to fsync, write caches, write barriers and a few examples
of sane and problematic setups as well as links to tools to verify a setup?

--
Best regards,
Hannes Dorbath