fsync vs open_sync

I did a little test on the various options of fsync.

I'm not sure my tests are scientific enough for general publication or
evaluation, all I am doing is performaing a loop that inserts a value into
a table 1 million times.
create table testndx (value integer, name varchar);
create index testndx_val on testndx (value);

for(int i=0; i < 1000000; i++)
{  insert into testndx (value, name) values ('%d', 'test')