Toast all the system-table columns that seem to need it. It turns out

that giving pg_proc a toast table required solving the same problems
we'd have to solve for pg_class --- pg_proc is one of the relations
that gets bootstrapped in relcache.c.  Solution is to go back at the
end of initialization and read in the *real* pg_class row to replace
the phony entry created by formrdesc().  This should work as long as
there's no need to touch any toasted values during initialization,
which seems a reasonable assumption.
Although I did not add a toast-table for every single system table
with a varlena attribute, I believe that it would work to just do
ALTER TABLE pg_class CREATE TOAST TABLE.  So anyone who's really
intent on having several thousand ACL entries for a rel could do it.
NOTE: I didn't force initdb, but you must do one to see the effects
of this patch.

src/include/utils/relcache.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: relcache.h,v 1.20 2000/06/17 21:49:04 tgl Exp $
+ * $Id: relcache.h,v 1.21 2000/08/06 04:39:55 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -33,6 +33,12 @@ extern void RelationForgetRelation(Oid rid);
  */
 extern List *RelationGetIndexList(Relation relation);
 
+/*
+ * Routines for backend startup
+ */
+extern void RelationCacheInitialize(void);
+extern void RelationCacheInitializePhase2(void);
+
 /*
  * Routines for flushing/rebuilding relcache entries in various scenarios
  */
@@ -42,7 +48,6 @@ extern void RelationCacheInvalidate(void);
 
 extern void RelationRegisterRelation(Relation relation);
 extern void RelationPurgeLocalRelation(bool xactComitted);
-extern void RelationInitialize(void);
 
 extern void RelationCacheAbort(void);