UNIX File buffering disable?

Hello

I have heard that UNIX I/O buffer sometimes causes problems during
system crash because it keeps files which, application thinks, are
already written to disk. And then this changes go lost during crash.
Therefore I heard a recommendation, that dba's should disabled UNIX file
buffering on mountpoints where rdbms are running.

What about this? Any hints? What about PostgreSQL? Do we bypass this OS
buffering (fsync?) or should a dba do anything else?

How do I disable this I/O buffering?

Thanks for comments
Oli

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Oli Sennhauser
Database-Engineer (Oracle & PostgreSQL)
Rebenweg 6
CH - 8610 Uster / Switzerland

Phone (+41) 1 940 24 82 or Mobile (+41) 79 450 49 14
e-Mail oli(dot)sennhauser(at)bluewin(dot)ch
Website http://mypage.bluewin.ch/shinguz/PostgreSQL/

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