diff --git a/C/agc.c b/C/agc.c
index cb43a65ba..8e4a97ed5 100644
--- a/C/agc.c
+++ b/C/agc.c
@@ -31,6 +31,14 @@ static char     SccsId[] = "@(#)agc.c	1.3 3/15/90";
 STATIC_PROTO(void  RestoreEntries, (PropEntry *));
 STATIC_PROTO(void  ConvDBList, (Term, char *,CELL));
 
+static int agc_calls;
+
+static Int agc_collected;
+
+static Int tot_agc_time = 0; /* total time spent in GC */
+
+static Int tot_agc_recovered = 0; /* number of heap objects in all garbage collections */
+
 #define AtomMarkedBit 1
 
 static inline void
@@ -335,6 +343,7 @@ clean_atoms(void)
 #endif
 	*patm = at->NextOfAE;
 	atm = at->NextOfAE;
+	agc_collected += SizeOfBlock((char *)at);
 	FreeCodeSpace((char *)at);
       }
     }
@@ -353,6 +362,7 @@ clean_atoms(void)
 #endif
       *patm = at->NextOfAE;
       atm = at->NextOfAE;
+      agc_collected += SizeOfBlock((char *)at);
       FreeCodeSpace((char *)at);
     }
   }
@@ -361,8 +371,59 @@ clean_atoms(void)
 void
 atom_gc(void)
 {
+  int		gc_verbose = is_gc_verbose();
+  int           gc_trace = 0;
+  
+
+  Int		time_start, agc_time;
+  if (GetValue(AtomGcTrace) != TermNil)
+    gc_trace = 1;
+  agc_calls++;
+  agc_collected = 0;
+  if (gc_trace) {
+    YP_fprintf(YP_stderr, "[agc]\n");
+  } else if (gc_verbose) {
+    YP_fprintf(YP_stderr, "[AGC] Start of atom garbage collection %d:\n", agc_calls);
+  }
+  time_start = cputime();
+  /* get the number of active registers */
+  YAPEnterCriticalSection();
   mark_stacks();
   mark_atoms();
   clean_atoms();
-  LookupAtom("!");
+  YAPLeaveCriticalSection();
+  agc_time = cputime()-time_start;
+  tot_agc_time += agc_time;
+  tot_agc_recovered += agc_collected;
+  if (gc_verbose) {
+    YP_fprintf(YP_stderr, "[AGC] collected %d bytes.\n", agc_collected);
+    YP_fprintf(YP_stderr, "[AGC] GC %d took %g sec, total of %g sec doing GC so far.\n", agc_calls, (double)agc_time/1000, (double)tot_agc_time/1000);
+  }
+}
+
+static Int
+p_atom_gc(void)
+{
+#ifndef FIXED_STACKS
+  atom_gc();
+#endif  /* FIXED_STACKS */
+  return(TRUE);
+}
+
+static Int
+p_inform_agc(void)
+{
+  Term tn = MkIntegerTerm(tot_agc_time);
+  Term tt = MkIntegerTerm(agc_calls);
+  Term ts = MkIntegerTerm(tot_agc_recovered);
+
+  return(unify(tn, ARG2) && unify(tt, ARG1) && unify(ts, ARG3));
+
+}
+
+void 
+init_agc(void)
+{
+  InitCPred("$atom_gc", 0, p_atom_gc, 0);
+  InitCPred("$inform_agc", 3, p_inform_agc, 0);
 }
diff --git a/C/grow.c b/C/grow.c
index fe55a50be..d4a621e43 100644
--- a/C/grow.c
+++ b/C/grow.c
@@ -963,4 +963,5 @@ InitGrowPreds(void)
 	InitCPred("$inform_heap_overflows", 2, p_inform_heap_overflows, SafePredFlag);
 	InitCPred("$inform_stack_overflows", 2, p_inform_stack_overflows, SafePredFlag);
 	init_gc();
+	init_agc();
 }
diff --git a/C/heapgc.c b/C/heapgc.c
index 512da34d1..3f1188aee 100644
--- a/C/heapgc.c
+++ b/C/heapgc.c
@@ -3096,19 +3096,9 @@ p_gc(void)
   return(TRUE);
 }
 
-static Int
-p_atom_gc(void)
-{
-#ifndef FIXED_STACKS
-  atom_gc();
-#endif  /* FIXED_STACKS */
-  return(TRUE);
-}
-
 void 
 init_gc(void)
 {
   InitCPred("$gc", 0, p_gc, 0);
   InitCPred("$inform_gc", 3, p_inform_gc, 0);
-  InitCPred("$atom_gc", 0, p_atom_gc, 0);
 }
diff --git a/H/Yapproto.h b/H/Yapproto.h
index eac0b2dd0..1934d2981 100644
--- a/H/Yapproto.h
+++ b/H/Yapproto.h
@@ -10,7 +10,7 @@
 * File:		Yap.proto						 *
 * mods:									 *
 * comments:	Function declarations for YAP				 *
-* version:      $Id: Yapproto.h,v 1.19 2002-06-04 18:21:55 vsc Exp $	 *
+* version:      $Id: Yapproto.h,v 1.20 2002-06-05 03:59:50 vsc Exp $	 *
 *************************************************************************/
 
 /* prototype file for Yap */
@@ -64,6 +64,7 @@ Term    STD_PROTO(Module_Name, (CODEADDR));
 
 /* agc.c */
 void    STD_PROTO(atom_gc, (void));
+void    STD_PROTO(init_agc, (void));
 
 /* alloc.c */
 int	STD_PROTO(SizeOfBlock,(CODEADDR));
diff --git a/pl/utils.yap b/pl/utils.yap
index 22f61b0c0..96a71fe71 100644
--- a/pl/utils.yap
+++ b/pl/utils.yap
@@ -397,9 +397,10 @@ statistics :-
 	'$inform_stack_overflows'(NOfSO,TotSOTime),
 	'$inform_trail_overflows'(NOfTO,TotTOTime),
 	'$inform_gc'(NOfGC,TotGCTime,TotGCSize),
-	'$statistics'(Runtime,CPUtime,Walltime,HpSpa,HpInUse,HpMax,TrlSpa, TrlInUse,TrlMax,StkSpa, GlobInU, LocInU,GlobMax,LocMax,NOfHO,TotHOTime,NOfSO,TotSOTime,NOfTO,TotTOTime,NOfGC,TotGCTime,TotGCSize).
+	'$inform_agc'(NOfAGC,TotAGCTime,TotAGCSize),
+	'$statistics'(Runtime,CPUtime,Walltime,HpSpa,HpInUse,HpMax,TrlSpa, TrlInUse,TrlMax,StkSpa, GlobInU, LocInU,GlobMax,LocMax,NOfHO,TotHOTime,NOfSO,TotSOTime,NOfTO,TotTOTime,NOfGC,TotGCTime,TotGCSize,NOfAGC,TotAGCTime,TotAGCSize).
 
-'$statistics'(Runtime,CPUtime,Walltime,HpSpa,HpInUse,_HpMax,TrlSpa, TrlInUse,_TrlMax,StkSpa, GlobInU, LocInU,GlobMax,LocMax,NOfHO,TotHOTime,NOfSO,TotSOTime,NOfTO,TotTOTime,NOfGC,TotGCTime,TotGCSize) :-
+'$statistics'(Runtime,CPUtime,Walltime,HpSpa,HpInUse,_HpMax,TrlSpa, TrlInUse,_TrlMax,StkSpa, GlobInU, LocInU,GlobMax,LocMax,NOfHO,TotHOTime,NOfSO,TotSOTime,NOfTO,TotTOTime,NOfGC,TotGCTime,TotGCSize,NOfAGC,TotAGCTime,TotAGCSize) :-
 	TotalMemory is HpSpa+StkSpa+TrlSpa,
 	'$format'(user_error,"memory (total)~t~d bytes~35+~n", [TotalMemory]),
 	'$format'(user_error,"   program space~t~d bytes~35+", [HpSpa]),
@@ -427,6 +428,9 @@ statistics :-
 	TotGCTimeF is float(TotGCTime)/1000,
 	'$format'(user_error,"~t~3f~12+ sec. for ~w garbage collections which collected ~d bytes~n",
 	       [TotGCTimeF,NOfGC,TotGCSize]),
+	TotAGCTimeF is float(TotAGCTime)/1000,
+	'$format'(user_error,"~t~3f~12+ sec. for ~w atom garbage collections which collected ~d bytes~n",
+	       [TotAGCTimeF,NOfAGC,TotAGCSize]),
 	RTime is float(Runtime)/1000,
 	'$format'(user_error,"~t~3f~12+ sec. runtime~n", [RTime]),
 	CPUTime is float(CPUtime)/1000,
@@ -434,7 +438,7 @@ statistics :-
 	WallTime is float(Walltime)/1000,
 	'$format'(user_error,"~t~3f~12+ sec. elapsed time~n~n", [WallTime]),
 	fail.
-'$statistics'(_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_).
+'$statistics'(_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_,_).
 
 statistics(runtime,[T,L]) :-
 	'$runtime'(T,L).