Daniel Henrique Debonzi <debonzi@gwyddion.com> writes:
> Does anybody knows how can I change the size (something about 4Mb) of
> the files inside the pg_xlog directory
You can't, short of hacking the source code (and I'm not sure it's a
one-line change if you do...)
> and how can I have no more than one file inside it.
Can't do that either. In a low-traffic database you could reasonably
expect to have no more than two xlog files most of the time. Set
checkpoint_segments to 1 to minimize the space usage.
regards, tom lane