Vivek Khera wrote:
> >>>>> "BM" == Bruce Momjian <pgman@candle.pha.pa.us> writes:
>
> >> Sounds reasonable to me. Are there many / any scenarios where a plain
> >> fsync would be faster than open_sync?
>
> BM> Yes. If you were doing multiple WAL writes before transaction fsync,
> BM> you would be fsyncing every write, rather than doing two writes and
> BM> fsync'ing them both. I wonder if larger transactions would find
> BM> open_sync slower?
>
> consider loading a large database from a backup dump. one big
> transaction during the COPY. I don't know the implications it has on
> this scenario, though.
COPY only does fsync on COPY completion, so I am not sure there are
enough fsync's there to make a difference.
--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073