Re: [PATCH] Revert default wal_sync_method to fdatasync on Linux 2.6.33+

On Friday 05 November 2010 22:53:37 Greg Smith wrote:
> > If open_dsync is so bad for performance on Linux, maybe it's bad
> > everywhere?  Should we be rethinking the default preference order?
> >
> >   
> 
> And I've seen the expected sync write performance gain over fdatasync on 
> a system with a battery-backed cache running VxFS on Linux, because 
> working open_[d]sync means O_DIRECT writes bypassing the OS cache, and 
> therefore reducing cache pollution from WAL writes.
Which looks like a setup where you definitely need to know what you do. I.e. 
don't need support from wal_sync_method by default being open_fdatasync...

Andres