Re: Allowing WAL fsync to be done via O_SYNC

I was wondering if the multiple writes performed to the XLOG could be
grouped into one write().  Seems everyone agrees:
	
	fdatasync/O_DSYNC is better then plain fsync/O_SYNC

and the O_* flags are better than fsync() if we are doing only one write
before every fsync.  It seems the only open question is now often we do
multiple writes before fsync, and if that is ever faster than putting
the O_* on the file for all writes.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
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