Log Message:
-----------
Add:
> * Improve the background writer
>
> Allow the background writer to more efficiently write dirty buffers
> from the end of the LRU cache and use a clock sweep algorithm to
> write other dirty buffers to reduced checkpoint I/O
Modified Files:
--------------
pgsql/doc:
TODO (r1.1426 -> r1.1427)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/TODO.diff?r1=1.1426&r2=1.1427)