perf(core): filter empty named rows once and cover the named overview budget

overviewWorkspaces drops empty, non-current named rows before grouping instead of on every numbered row, clears its named scratch after use, and documents that the result keeps the last rows reachable. overviewSlots.at moves to the tests. TestPublishOverviewAllocations gains a named case with the boundary divider (5 allocs).

commit: 7898c05b558b33395f2980fc8ef72679dd898f55
author: brice · 6d ago · 2026-10-16 14:08 UTC
parent: 08c5e16
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

3 files · +50 -20

M internal/core/overview.go +7 -14


@@ -328,7 +328,8 @@ func restoreRow(w *Workspace, s rowSnapshot) {
328	328		// other empty rows are skipped unless current.
329	329		//
330	330		// The result is the monitor's scratch, rebuilt by the next call: callers
331		-	// read it and drop it before calling again (Clone it to keep it).
	331	+	// read it and drop it before calling again (Clone it to keep it). It keeps
	332	+	// the last result's workspaces reachable until then.
332	333		func (m Monitor) overviewWorkspaces() []Workspace {
333	334		fallback := m.Workspaces[0]
334	335		for _, w := range m.Workspaces {

@@ -344,10 +345,11 @@ func (m Monitor) overviewWorkspaces() []Workspace {
344	345		}
345	346		return len(m.named)
346	347		}
	348	+	cur := m.Current()
347	349		named := append(m.ovNamed[:0], m.hidden...)
	350	+	named = slices.DeleteFunc(named, func(n *Workspace) bool { return n.empty() && n != cur })
348	351		m.ovNamed = named
349	352		slices.SortStableFunc(named, func(a, b *Workspace) int { return rank(a) - rank(b) })
350		-	cur := m.Current()
351	353		rows := m.ovList[:0]
352	354		for _, w := range m.Workspaces {
353	355		// The row is kept when occupied, current or anchoring a named

@@ -355,9 +357,6 @@ func (m Monitor) overviewWorkspaces() []Workspace {
355	357		at := len(rows)
356	358		rows = append(rows, w)
357	359		for _, n := range named {
358		-	if n.empty() && n != cur {
359		-	continue
360		-	}
361	360		anchor := n.overviewAfter
362	361		if indexOf(m.Workspaces, anchor) < 0 {
363	362		anchor = fallback

@@ -370,9 +369,9 @@ func (m Monitor) overviewWorkspaces() []Workspace {
370	369		rows = rows[:at]
371	370		}
372	371		}
373		-	// Clear the unused tails so a workspace gone from this monitor is not
374		-	// kept reachable by the scratch.
375		-	clear(named[len(named):cap(named)])
	372	+	// named is only needed here; the rows' tail is cleared so the scratch
	373	+	// holds no more than the last result.
	374	+	clear(named[:cap(named)])
376	375		clear(rows[len(rows):cap(rows)])
377	376		m.ovList = rows
378	377		return rows

@@ -701,12 +700,6 @@ func (s overviewSlots) add(w Workspace, r Rect) {
701	700		s.n++
702	701		}
703	702
704		-	// at is the slot of w, the zero Rect if it has none.
705		-	func (s overviewSlots) at(w Workspace) Rect {
706		-	r, _ := s.lookup(w)
707		-	return r
708		-	}
709		-
710	703		// lookup is the slot of w, if it has one.
711	704		func (s overviewSlots) lookup(w Workspace) (Rect, bool) {
712	705		for i := range s.n {

 // other empty rows are skipped unless current.
 //
 // The result is the monitor's scratch, rebuilt by the next call: callers
-// read it and drop it before calling again (Clone it to keep it).
+// read it and drop it before calling again (Clone it to keep it). It keeps
+// the last result's workspaces reachable until then.
 func (m *Monitor) overviewWorkspaces() []*Workspace {
 	fallback := m.Workspaces[0]
 	for _, w := range m.Workspaces {
 		}
 		return len(m.named)
 	}
+	cur := m.Current()
 	named := append(m.ovNamed[:0], m.hidden...)
+	named = slices.DeleteFunc(named, func(n *Workspace) bool { return n.empty() && n != cur })
 	m.ovNamed = named
 	slices.SortStableFunc(named, func(a, b *Workspace) int { return rank(a) - rank(b) })
-	cur := m.Current()
 	rows := m.ovList[:0]
 	for _, w := range m.Workspaces {
 		// The row is kept when occupied, current or anchoring a named
 		at := len(rows)
 		rows = append(rows, w)
 		for _, n := range named {
-			if n.empty() && n != cur {
-				continue
-			}
 			anchor := n.overviewAfter
 			if indexOf(m.Workspaces, anchor) < 0 {
 				anchor = fallback
 			rows = rows[:at]
 		}
 	}
-	// Clear the unused tails so a workspace gone from this monitor is not
+	// named is only needed here; the rows' tail is cleared so the scratch
-	// kept reachable by the scratch.
+	// holds no more than the last result.
-	clear(named[len(named):cap(named)])
+	clear(named[:cap(named)])
 	clear(rows[len(rows):cap(rows)])
 	m.ovList = rows
 	return rows
 	s.n++
 }
-// at is the slot of w, the zero Rect if it has none.
-func (s *overviewSlots) at(w *Workspace) Rect {
-	r, _ := s.lookup(w)
-	return r
-}
 // lookup is the slot of w, if it has one.
 func (s *overviewSlots) lookup(w *Workspace) (Rect, bool) {
 	for i := range s.n {

M internal/core/overview_test.go +6 -0


@@ -763,3 +763,9 @@ func TestOverviewFingerScroll(t *testing.T) {
763	763		t.Fatal("continuous scroll held by the finger scroll")
764	764		}
765	765		}
	766	+
	767	+	// at is the slot of w, the zero Rect if it has none.
	768	+	func (s overviewSlots) at(w Workspace) Rect {
	769	+	r, _ := s.lookup(w)
	770	+	return r
	771	+	}


@@ -763,3 +763,9 @@ func TestOverviewFingerScroll(t *testing.T) {
763	t.Fatal("continuous scroll held by the finger scroll")	763		t.Fatal("continuous scroll held by the finger scroll")
764	}	764		}
765	}	765		}
		766	+
		767	+	// at is the slot of w, the zero Rect if it has none.
		768	+	func (s overviewSlots) at(w Workspace) Rect {
		769	+	r, _ := s.lookup(w)
		770	+	return r
		771	+	}

M internal/core/publish_alloc_test.go +37 -6


@@ -24,12 +24,13 @@ import (
24	24		// (copied only when it changed). What is left is the scenes themselves
25	25		// (windows, separators, the scene set). Leaving entries (a closed window
26	26		// still fading) add none: 3, less than a frame with six moving windows
27		-	// (fewer configure targets). The opening overview costs 6 (7 under -race),
28		-	// 4 alone: it was 11 and 13 when it rebuilt the row map, the neighbor list,
29		-	// the workspace order (groups map, hidden clone) and the outline slice
30		-	// (appended onto the dividers) every frame; the rows are now a fixed array,
31		-	// the order and dividers monitor scratch, and the scene's separators one
32		-	// slice. What is left is the scene, the stack items and the preview rows.
	27	+	// (fewer configure targets). The opening overview costs 4 alone and 6 with
	28	+	// neighbors (5 and 7 under -race); it was 11 and 13 when it rebuilt the row
	29	+	// map, the neighbor list, the workspace order (groups map, hidden clone) and
	30	+	// the outline slice (appended onto the dividers) every frame. The rows are
	31	+	// now a fixed array, the order and dividers monitor scratch, and the scene's
	32	+	// separators one slice. What is left is the scene, the stack items and the
	33	+	// preview rows.
33	34		const (
34	35		publishAllocBudget = 5
35	36		publishLeavingAllocBudget = 3

@@ -254,6 +255,36 @@ func TestPublishOverviewAllocations(t *testing.T) {
254	255		})
255	256		}
256	257		}
	258	+	// A named row below its anchor adds the boundary divider: the scene
	259	+	// copies it into its own separators, one slice like the outline alone.
	260	+	t.Run("named", func(t *testing.T) {
	261	+	c := publishRig(t, 1)
	262	+	sc := c.cur()
	263	+	m := sc.mon
	264	+	m.SetNamed([]NamedWorkspace{{Name: "dev"}})
	265	+	m.ToggleNamed("dev")
	266	+	m.AddWindow(30)
	267	+	m.ToggleNamed("dev")
	268	+	sc.arrange()
	269	+	c.refreshShown()
	270	+	now := time.Now()
	271	+	shots := c.snapshot(now)
	272	+	m.ToggleOverview()
	273	+	c.transition(shots, now)
	274	+	step := publishStep(t, c, nil)
	275	+	step()
	276	+	if _, dividers := m.overviewRows(); len(dividers) != 1 \|\| !m.ov.open \|\| len(sc.rects) == 0 {
	277	+	t.Fatalf("setup: %d dividers, overview %v, rects %d", len(dividers), m.ov.open, len(sc.rects))
	278	+	}
	279	+	n := testing.AllocsPerRun(50, step)
	280	+	t.Logf("named overview allocs per step = %v", n)
	281	+	if len(sc.rects) == 0 {
	282	+	t.Fatal("card motions settled during the measure")
	283	+	}
	284	+	if n > publishOverviewAllocBudget {
	285	+	t.Errorf("named overview publish allocs per frame = %v, budget %d", n, publishOverviewAllocBudget)
	286	+	}
	287	+	})
257	288		// The column switcher's cards are previews too: a held switch shows
258	289		// them, and a publish while their motions run costs a plain frame.
259	290		t.Run("switcher", func(t *testing.T) {


@@ -24,12 +24,13 @@ import (
24		// (copied only when it changed). What is left is the scenes themselves	24		// (copied only when it changed). What is left is the scenes themselves
25		// (windows, separators, the scene set). Leaving entries (a closed window	25		// (windows, separators, the scene set). Leaving entries (a closed window
26		// still fading) add none: 3, less than a frame with six moving windows	26		// still fading) add none: 3, less than a frame with six moving windows
27	-	// (fewer configure targets). The opening overview costs 6 (7 under -race),	27	+	// (fewer configure targets). The opening overview costs 4 alone and 6 with
28	-	// 4 alone: it was 11 and 13 when it rebuilt the row map, the neighbor list,	28	+	// neighbors (5 and 7 under -race); it was 11 and 13 when it rebuilt the row
29	-	// the workspace order (groups map, hidden clone) and the outline slice	29	+	// map, the neighbor list, the workspace order (groups map, hidden clone) and
30	-	// (appended onto the dividers) every frame; the rows are now a fixed array,	30	+	// the outline slice (appended onto the dividers) every frame. The rows are
31	-	// the order and dividers monitor scratch, and the scene's separators one	31	+	// now a fixed array, the order and dividers monitor scratch, and the scene's
32	-	// slice. What is left is the scene, the stack items and the preview rows.	32	+	// separators one slice. What is left is the scene, the stack items and the
			33	+	// preview rows.
33		const (	34		const (
34		publishAllocBudget = 5	35		publishAllocBudget = 5
35		publishLeavingAllocBudget = 3	36		publishLeavingAllocBudget = 3

@@ -254,6 +255,36 @@ func TestPublishOverviewAllocations(t *testing.T) {
254		})	255		})
255		}	256		}
256		}	257		}
			258	+	// A named row below its anchor adds the boundary divider: the scene
			259	+	// copies it into its own separators, one slice like the outline alone.
			260	+	t.Run("named", func(t *testing.T) {
			261	+	c := publishRig(t, 1)
			262	+	sc := c.cur()
			263	+	m := sc.mon
			264	+	m.SetNamed([]NamedWorkspace{{Name: "dev"}})
			265	+	m.ToggleNamed("dev")
			266	+	m.AddWindow(30)
			267	+	m.ToggleNamed("dev")
			268	+	sc.arrange()
			269	+	c.refreshShown()
			270	+	now := time.Now()
			271	+	shots := c.snapshot(now)
			272	+	m.ToggleOverview()
			273	+	c.transition(shots, now)
			274	+	step := publishStep(t, c, nil)
			275	+	step()
			276	+	if _, dividers := m.overviewRows(); len(dividers) != 1 \|\| !m.ov.open \|\| len(sc.rects) == 0 {
			277	+	t.Fatalf("setup: %d dividers, overview %v, rects %d", len(dividers), m.ov.open, len(sc.rects))
			278	+	}
			279	+	n := testing.AllocsPerRun(50, step)
			280	+	t.Logf("named overview allocs per step = %v", n)
			281	+	if len(sc.rects) == 0 {
			282	+	t.Fatal("card motions settled during the measure")
			283	+	}
			284	+	if n > publishOverviewAllocBudget {
			285	+	t.Errorf("named overview publish allocs per frame = %v, budget %d", n, publishOverviewAllocBudget)
			286	+	}
			287	+	})
257		// The column switcher's cards are previews too: a held switch shows	288		// The column switcher's cards are previews too: a held switch shows
258		// them, and a publish while their motions run costs a plain frame.	289		// them, and a publish while their motions run costs a plain frame.
259		t.Run("switcher", func(t *testing.T) {	290		t.Run("switcher", func(t *testing.T) {