Log Message:
-----------
Replace ReadBuffer to ReadBufferWithStrategy in all vacuum-involved places
to implement limited-size "ring" of buffers for VACUUM for GIN & GIST
Modified Files:
--------------
pgsql/src/backend/access/gin:
ginvacuum.c (r1.12 -> r1.13)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/ginvacuum.c.diff?r1=1.12&r2=1.13)
pgsql/src/backend/access/gist:
gistvacuum.c (r1.29 -> r1.30)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gist/gistvacuum.c.diff?r1=1.29&r2=1.30)