diff --git a/src/runtime/mgc.go b/src/runtime/mgc.go
index 87b6a748e1..38f343164c 100644
--- a/src/runtime/mgc.go
+++ b/src/runtime/mgc.go
@@ -131,6 +131,7 @@ package runtime
 import (
 	"internal/cpu"
 	"internal/goarch"
+	"internal/goexperiment"
 	"internal/runtime/atomic"
 	"internal/runtime/gc"
 	"unsafe"
@@ -717,7 +718,7 @@ func gcStart(trigger gcTrigger) {
 			throw("p mcache not flushed")
 		}
 		// Initialize ptrBuf if necessary.
-		if p.gcw.ptrBuf == nil {
+		if goexperiment.GreenTeaGC && p.gcw.ptrBuf == nil {
 			p.gcw.ptrBuf = (*[gc.PageSize / goarch.PtrSize]uintptr)(persistentalloc(gc.PageSize, goarch.PtrSize, &memstats.gcMiscSys))
 		}
 	}
@@ -1233,14 +1234,7 @@ func gcMarkTermination(stw worldStop) {
 			})
 		}
 		if debug.gctrace > 1 {
-			for i := range pp.gcw.stats {
-				memstats.lastScanStats[i].spansDenseScanned += pp.gcw.stats[i].spansDenseScanned
-				memstats.lastScanStats[i].spanObjsDenseScanned += pp.gcw.stats[i].spanObjsDenseScanned
-				memstats.lastScanStats[i].spansSparseScanned += pp.gcw.stats[i].spansSparseScanned
-				memstats.lastScanStats[i].spanObjsSparseScanned += pp.gcw.stats[i].spanObjsSparseScanned
-				memstats.lastScanStats[i].sparseObjsScanned += pp.gcw.stats[i].sparseObjsScanned
-			}
-			clear(pp.gcw.stats[:])
+			pp.gcw.flushScanStats(&memstats.lastScanStats)
 		}
 		pp.pinnerCache = nil
 	})
@@ -1301,38 +1295,7 @@ func gcMarkTermination(stw worldStop) {
 		print("\n")
 
 		if debug.gctrace > 1 {
-			var (
-				spansDenseScanned     uint64
-				spanObjsDenseScanned  uint64
-				spansSparseScanned    uint64
-				spanObjsSparseScanned uint64
-				sparseObjsScanned     uint64
-			)
-			for _, stats := range memstats.lastScanStats {
-				spansDenseScanned += stats.spansDenseScanned
-				spanObjsDenseScanned += stats.spanObjsDenseScanned
-				spansSparseScanned += stats.spansSparseScanned
-				spanObjsSparseScanned += stats.spanObjsSparseScanned
-				sparseObjsScanned += stats.sparseObjsScanned
-			}
-			totalObjs := sparseObjsScanned + spanObjsSparseScanned + spanObjsDenseScanned
-			totalSpans := spansSparseScanned + spansDenseScanned
-			print("scan: total ", sparseObjsScanned, "+", spanObjsSparseScanned, "+", spanObjsDenseScanned, "=", totalObjs, " objs")
-			print(", ", spansSparseScanned, "+", spansDenseScanned, "=", totalSpans, " spans\n")
-			for i, stats := range memstats.lastScanStats {
-				if stats == (sizeClassScanStats{}) {
-					continue
-				}
-				totalObjs := stats.sparseObjsScanned + stats.spanObjsSparseScanned + stats.spanObjsDenseScanned
-				totalSpans := stats.spansSparseScanned + stats.spansDenseScanned
-				if i == 0 {
-					print("scan: class L ")
-				} else {
-					print("scan: class ", gc.SizeClassToSize[i], "B ")
-				}
-				print(stats.sparseObjsScanned, "+", stats.spanObjsSparseScanned, "+", stats.spanObjsDenseScanned, "=", totalObjs, " objs")
-				print(", ", stats.spansSparseScanned, "+", stats.spansDenseScanned, "=", totalSpans, " spans\n")
-			}
+			dumpScanStats()
 		}
 		printunlock()
 	}
diff --git a/src/runtime/mgcmark_greenteagc.go b/src/runtime/mgcmark_greenteagc.go
index 84cb6c99ab..75c347b9e9 100644
--- a/src/runtime/mgcmark_greenteagc.go
+++ b/src/runtime/mgcmark_greenteagc.go
@@ -763,3 +763,57 @@ func heapBitsSmallForAddrInline(spanBase, addr, elemsize uintptr) uintptr {
 	}
 	return read
 }
+
+type sizeClassScanStats struct {
+	spansDenseScanned     uint64
+	spanObjsDenseScanned  uint64
+	spansSparseScanned    uint64
+	spanObjsSparseScanned uint64
+	sparseObjsScanned     uint64
+}
+
+func dumpScanStats() {
+	var (
+		spansDenseScanned     uint64
+		spanObjsDenseScanned  uint64
+		spansSparseScanned    uint64
+		spanObjsSparseScanned uint64
+		sparseObjsScanned     uint64
+	)
+	for _, stats := range memstats.lastScanStats {
+		spansDenseScanned += stats.spansDenseScanned
+		spanObjsDenseScanned += stats.spanObjsDenseScanned
+		spansSparseScanned += stats.spansSparseScanned
+		spanObjsSparseScanned += stats.spanObjsSparseScanned
+		sparseObjsScanned += stats.sparseObjsScanned
+	}
+	totalObjs := sparseObjsScanned + spanObjsSparseScanned + spanObjsDenseScanned
+	totalSpans := spansSparseScanned + spansDenseScanned
+	print("scan: total ", sparseObjsScanned, "+", spanObjsSparseScanned, "+", spanObjsDenseScanned, "=", totalObjs, " objs")
+	print(", ", spansSparseScanned, "+", spansDenseScanned, "=", totalSpans, " spans\n")
+	for i, stats := range memstats.lastScanStats {
+		if stats == (sizeClassScanStats{}) {
+			continue
+		}
+		totalObjs := stats.sparseObjsScanned + stats.spanObjsSparseScanned + stats.spanObjsDenseScanned
+		totalSpans := stats.spansSparseScanned + stats.spansDenseScanned
+		if i == 0 {
+			print("scan: class L ")
+		} else {
+			print("scan: class ", gc.SizeClassToSize[i], "B ")
+		}
+		print(stats.sparseObjsScanned, "+", stats.spanObjsSparseScanned, "+", stats.spanObjsDenseScanned, "=", totalObjs, " objs")
+		print(", ", stats.spansSparseScanned, "+", stats.spansDenseScanned, "=", totalSpans, " spans\n")
+	}
+}
+
+func (w *gcWork) flushScanStats(dst *[gc.NumSizeClasses]sizeClassScanStats) {
+	for i := range w.stats {
+		dst[i].spansDenseScanned += w.stats[i].spansDenseScanned
+		dst[i].spanObjsDenseScanned += w.stats[i].spanObjsDenseScanned
+		dst[i].spansSparseScanned += w.stats[i].spansSparseScanned
+		dst[i].spanObjsSparseScanned += w.stats[i].spanObjsSparseScanned
+		dst[i].sparseObjsScanned += w.stats[i].sparseObjsScanned
+	}
+	clear(w.stats[:])
+}
diff --git a/src/runtime/mgcmark_nogreenteagc.go b/src/runtime/mgcmark_nogreenteagc.go
index 08f726a980..c0ca5c21ea 100644
--- a/src/runtime/mgcmark_nogreenteagc.go
+++ b/src/runtime/mgcmark_nogreenteagc.go
@@ -6,6 +6,8 @@
 
 package runtime
 
+import "internal/runtime/gc"
+
 func (s *mspan) markBitsForIndex(objIndex uintptr) markBits {
 	bytep, mask := s.gcmarkBits.bitp(objIndex)
 	return markBits{bytep, mask, objIndex}
@@ -78,3 +80,33 @@ func (w *gcWork) tryGetSpan(steal bool) objptr {
 func scanSpan(p objptr, gcw *gcWork) {
 	throw("unimplemented")
 }
+
+type sizeClassScanStats struct {
+	sparseObjsScanned uint64
+}
+
+func dumpScanStats() {
+	var sparseObjsScanned uint64
+	for _, stats := range memstats.lastScanStats {
+		sparseObjsScanned += stats.sparseObjsScanned
+	}
+	print("scan: total ", sparseObjsScanned, " objs\n")
+	for i, stats := range memstats.lastScanStats {
+		if stats == (sizeClassScanStats{}) {
+			continue
+		}
+		if i == 0 {
+			print("scan: class L ")
+		} else {
+			print("scan: class ", gc.SizeClassToSize[i], "B ")
+		}
+		print(stats.sparseObjsScanned, " objs\n")
+	}
+}
+
+func (w *gcWork) flushScanStats(dst *[gc.NumSizeClasses]sizeClassScanStats) {
+	for i := range w.stats {
+		dst[i].sparseObjsScanned += w.stats[i].sparseObjsScanned
+	}
+	clear(w.stats[:])
+}
diff --git a/src/runtime/mstats.go b/src/runtime/mstats.go
index 29ace5ec16..e34f0b10ea 100644
--- a/src/runtime/mstats.go
+++ b/src/runtime/mstats.go
@@ -49,14 +49,6 @@ type mstats struct {
 	enablegc bool
 }
 
-type sizeClassScanStats struct {
-	spansDenseScanned     uint64
-	spanObjsDenseScanned  uint64
-	spansSparseScanned    uint64
-	spanObjsSparseScanned uint64
-	sparseObjsScanned     uint64
-}
-
 var memstats mstats
 
 // A MemStats records statistics about the memory allocator.