Re: Multicolumn index corruption on 8.4 beta 2

Alvaro, Kevin,

>> Yeah, AFAICT the writes are handed off to the operating system (just
>> not synced), so if it flushes its caches sanely at all there
>> shouldn't be a problem.
>
> I would certainly *hope* that's the case.  We sometimes use fsync=off
> for conversions, where we plan to just start over if the conversion
> crashes, and set it to on when the conversion is done.  It would be
> disturbing to discover that fsync=off also means "don't bother to
> write dirty buffers to the OS before shutdown."

It doesn't.  But what I don't trust, and the *first* place I'd look for 
problems, is whether the OS flushes *all* dirty buffers to disk in the 
event the application gets killed.

That's why I want more information on Floris' case.  Was 8.4 killed or 
shut down with -m immediate?  Or the os rebooted with 8.4 running?

-- 
Josh Berkus
PostgreSQL Experts Inc.
www.pgexperts.com