Compare file sync methods with one 8k write:Odd. Which filesystem, which kernel? It seems fdatasync is broken and syncs the inode, too.
(o_dsync unavailable) open o_sync, write 6.270724
write, fdatasync 13.275225
write, fsync, 13.359847
-- Manfred
---------------------------(end of broadcast)--------------------------- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match