Re: win32 performance - fsync question - Mailing list pgsql-hackers

From Andrew Dunstan
Subject Re: win32 performance - fsync question
Date
Msg-id 4214B68C.8000901@dunslane.net
Whole thread Raw
In response to Re: win32 performance - fsync question  ("E.Rodichev" <er@sai.msu.su>)
Responses Re: win32 performance - fsync question  (lsunley@mb.sympatico.ca)
Re: win32 performance - fsync question  (Evgeny Rodichev <er@sai.msu.su>)
List pgsql-hackers

E.Rodichev wrote:

>
> This problem is addressed by file system (fsck, journalling etc.).
> Is it reasonable to handle it directly within application?
>
>

In the words of the Duke of Wellington, "If you believe that you'll 
believe anything."

Please review past discussions on the mailing lists on this point.

BTW, most journalling file systems do not guarantee file integrity, only 
file metadata integrity. In particular, I believe this is tru of NTFS 
(and whether it even does that has been debated).

So by all means turn off fsync if you want the performance gain *and* 
you accept the risk. But if you do, don't come crying later that your 
data has been lost or corrupted.

(the results are interesting, though - with fsync off Windows and Linux 
are in the same performance ballpark.)

cheers

andrew


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