diff --git a/src/runtime/mcentral.go b/src/runtime/mcentral.go
index be3820a9a5..8f9c529539 100644
--- a/src/runtime/mcentral.go
+++ b/src/runtime/mcentral.go
@@ -43,6 +43,10 @@ func (c *mcentral) cacheSpan() *mspan {
 	deductSweepCredit(spanBytes, 0)
 
 	lock(&c.lock)
+	traceDone := false
+	if trace.enabled {
+		traceGCSweepStart()
+	}
 	sg := mheap_.sweepgen
 retry:
 	var s *mspan
@@ -92,6 +96,10 @@ retry:
 		// all subsequent ones must also be either swept or in process of sweeping
 		break
 	}
+	if trace.enabled {
+		traceGCSweepDone()
+		traceDone = true
+	}
 	unlock(&c.lock)
 
 	// Replenish central list if empty.
@@ -106,6 +114,9 @@ retry:
 	// At this point s is a non-empty span, queued at the end of the empty list,
 	// c is unlocked.
 havespan:
+	if trace.enabled && !traceDone {
+		traceGCSweepDone()
+	}
 	cap := int32((s.npages << _PageShift) / s.elemsize)
 	n := cap - int32(s.allocCount)
 	if n == 0 || s.freeindex == s.nelems || uintptr(s.allocCount) == s.nelems {
diff --git a/src/runtime/mgcsweep.go b/src/runtime/mgcsweep.go
index bdd9e517d4..0c4a7ccc02 100644
--- a/src/runtime/mgcsweep.go
+++ b/src/runtime/mgcsweep.go
@@ -190,7 +190,7 @@ func (s *mspan) sweep(preserve bool) bool {
 	}
 
 	if trace.enabled {
-		traceGCSweepStart()
+		traceGCSweepSpan()
 	}
 
 	atomic.Xadd64(&mheap_.pagesSwept, int64(s.npages))
@@ -364,9 +364,6 @@ func (s *mspan) sweep(preserve bool) bool {
 		// it on the swept in-use list.
 		mheap_.sweepSpans[sweepgen/2%2].push(s)
 	}
-	if trace.enabled {
-		traceGCSweepDone()
-	}
 	return res
 }
 
@@ -394,6 +391,10 @@ func deductSweepCredit(spanBytes uintptr, callerSweepPages uintptr) {
 		return
 	}
 
+	if trace.enabled {
+		traceGCSweepStart()
+	}
+
 	// Account for this span allocation.
 	spanBytesAlloc := atomic.Xadd64(&mheap_.spanBytesAlloc, int64(spanBytes))
 
@@ -405,6 +406,10 @@ func deductSweepCredit(spanBytes uintptr, callerSweepPages uintptr) {
 			break
 		}
 	}
+
+	if trace.enabled {
+		traceGCSweepDone()
+	}
 }
 
 // reimburseSweepCredit records that unusableBytes bytes of a
diff --git a/src/runtime/mheap.go b/src/runtime/mheap.go
index 80d925cac6..e1b3b184e8 100644
--- a/src/runtime/mheap.go
+++ b/src/runtime/mheap.go
@@ -576,7 +576,13 @@ func (h *mheap) alloc_m(npage uintptr, sizeclass int32, large bool) *mspan {
 		// If GC kept a bit for whether there were any marks
 		// in a span, we could release these free spans
 		// at the end of GC and eliminate this entirely.
+		if trace.enabled {
+			traceGCSweepStart()
+		}
 		h.reclaim(npage)
+		if trace.enabled {
+			traceGCSweepDone()
+		}
 	}
 
 	// transfer stats from cache to global
diff --git a/src/runtime/runtime2.go b/src/runtime/runtime2.go
index 50e39acaa5..b16735ac46 100644
--- a/src/runtime/runtime2.go
+++ b/src/runtime/runtime2.go
@@ -490,6 +490,11 @@ type p struct {
 
 	tracebuf traceBufPtr
 
+	// traceSweep indicates the next traceGCSweepSpan should emit
+	// a sweep start event. This is used to defer the sweep start
+	// event until a span has actually been swept.
+	traceSweep bool
+
 	palloc persistentAlloc // per-P to avoid mutex
 
 	// Per-P GC state
diff --git a/src/runtime/trace.go b/src/runtime/trace.go
index 93d52a9844..375f0b76b7 100644
--- a/src/runtime/trace.go
+++ b/src/runtime/trace.go
@@ -932,12 +932,39 @@ func traceGCScanDone() {
 	traceEvent(traceEvGCScanDone, -1)
 }
 
+// traceGCSweepStart prepares to trace a sweep loop. This does not
+// emit any events until traceGCSweepSpan is called.
+//
+// traceGCSweepStart must be paired with traceGCSweepDone and there
+// must be no preemption points between these two calls.
 func traceGCSweepStart() {
-	traceEvent(traceEvGCSweepStart, 1)
+	// Delay the actual GCSweepStart event until the first span
+	// sweep. If we don't sweep anything, don't emit any events.
+	_p_ := getg().m.p.ptr()
+	if _p_.traceSweep {
+		throw("double traceGCSweepStart")
+	}
+	_p_.traceSweep = true
+}
+
+// traceGCSweepSpan traces the sweep of a single page.
+//
+// This may be called outside a traceGCSweepStart/traceGCSweepDone
+// pair; however, it will not emit any trace events in this case.
+func traceGCSweepSpan() {
+	_p_ := getg().m.p.ptr()
+	if _p_.traceSweep {
+		traceEvent(traceEvGCSweepStart, 1)
+		_p_.traceSweep = false
+	}
 }
 
 func traceGCSweepDone() {
-	traceEvent(traceEvGCSweepDone, -1)
+	_p_ := getg().m.p.ptr()
+	if !_p_.traceSweep {
+		traceEvent(traceEvGCSweepDone, -1)
+	}
+	_p_.traceSweep = false
 }
 
 func traceGCMarkAssistStart() {