perf: stop rewriting unchanged sessions every pass and share one app snapshot per poll

internal/cli/app.go

@@ -7,6 +7,8 @@ import (
 	"io"
 	"log/slog"
 	"os"
+	"strings"
+	"time"
 
 	"github.com/labstack/driga/internal/cleanup"
 	"github.com/labstack/driga/internal/config"
@@ -21,8 +23,10 @@ import (
 
 // AppCmd opens the desktop app, or focuses the running one.
 type AppCmd struct {
-	NotificationStdin bool   `hidden:"" help:"Read a notification target from standard input."`
-	Notification      string `hidden:"" help:"Desktop notification event target."`
+	CPUProfile        string        `name:"cpu-profile" type:"path" help:"Write a CPU profile of the app to this file."`
+	ProfileFor        time.Duration `name:"profile-for" default:"2m" help:"How long --cpu-profile records before it stops."`
+	NotificationStdin bool          `hidden:"" help:"Read a notification target from standard input."`
+	Notification      string        `hidden:"" help:"Desktop notification event target."`
 }
 
 var (
@@ -47,16 +51,24 @@ var (
 func AppLaunch(args []string) bool {
 	login := len(args) == 0 && os.Getenv("DRIGA_APP") != "1" && openedAtLogin()
 	app := appLaunch(os.Getenv, login, args)
-	systemLaunch = app && (len(args) == 0 || len(args) > 1 && (args[1] == "--notification" || args[1] == "--notification-stdin") && os.Getenv("DRIGA_APP") == "1")
+	systemLaunch = app && (len(args) == 0 || os.Getenv("DRIGA_APP") == "1")
 	_ = os.Unsetenv("DRIGA_APP")
 	return app
 }
 
 // appLaunch decides app mode: `driga app`, or a bare launch by the system.
 func appLaunch(env func(string) string, openedAtLogin bool, args []string) bool {
-	if len(args) >= 1 && args[0] == "app" && (len(args) == 1 || (args[1] == "--notification" || args[1] == "--notification-stdin")) {
-		return true
+	if len(args) > 0 && args[0] == "app" {
+		if len(args) == 1 {
+			return true
+		}
+		flag, _, _ := strings.Cut(args[1], "=")
+		switch flag {
+		case "--notification", "--notification-stdin", "--cpu-profile", "--profile-for":
+			return true
+		}
 	}
+
 	return len(args) == 0 && (env("DRIGA_APP") == "1" || openedAtLogin)
 }
 
@@ -104,9 +116,23 @@ func (c AppCmd) Run(g *Globals) error {
 		}
 		args = []string{"app", "--notification", c.Notification}
 	}
+	if c.CPUProfile != "" {
+		if len(args) == 0 {
+			args = []string{"app"}
+		}
+		args = append(args, "--cpu-profile", c.CPUProfile, "--profile-for", c.ProfileFor.String())
+	}
 	if handed, err := handOffApp(systemLaunch || c.NotificationStdin, args...); handed || err != nil {
 		return err
 	}
+	if c.CPUProfile != "" {
+		stopProfile, err := startCPUProfile(c.CPUProfile, c.ProfileFor)
+		if err != nil {
+			return err
+		}
+		defer stopProfile()
+	}
+
 	restore := appLogging()
 	defer restore()
 	// Opened from Finder or at login, an error here would reach no one: the

internal/cli/app_test.go

@@ -37,6 +37,8 @@ func TestAppLaunch(t *testing.T) {
 		{"command", "1", false, []string{"top"}, false},
 		{"command at login", "", true, []string{"top"}, false},
 		{"app", "", false, []string{"app"}, true},
+		{"profile equals", "", false, []string{"app", "--cpu-profile=/tmp/app.pprof"}, true},
+		{"profile", "", false, []string{"app", "--cpu-profile", "/tmp/app.pprof"}, true},
 		{"app help", "", false, []string{"app", "--help"}, false},
 		{"notification", "", false, []string{"app", "--notification", `{}`}, true},
 		{"other value", "0", false, nil, false},

internal/cli/collect_profile.go

@@ -1,14 +1,17 @@
 package cli
 
 import (
+	"encoding/json"
 	"os"
+	"runtime"
 	"runtime/pprof"
 	"sync"
 	"time"
 )
 
-// startCPUProfile records the collector's CPU use into path for d and writes
-// allocations to path + ".alloc", so the live service can be measured in place.
+// startCPUProfile records CPU use into path for d, cumulative allocations to
+// path + ".alloc", a final collected heap to ".heap", and memory/goroutine
+// samples every five seconds to ".mem.jsonl".
 // The returned stop is idempotent and flushes early on shutdown.
 func startCPUProfile(path string, d time.Duration) (func(), error) {
 	f, err := os.Create(path)
@@ -25,13 +28,54 @@ func startCPUProfile(path string, d time.Duration) (func(), error) {
 		alloc.Close()
 		return nil, err
 	}
+	memory, err := os.Create(path + ".mem.jsonl")
+	if err != nil {
+		pprof.StopCPUProfile()
+		f.Close()
+		alloc.Close()
+		return nil, err
+	}
+	done, sampled := make(chan struct{}), make(chan struct{})
+	go func() {
+		defer close(sampled)
+		defer memory.Close()
+		ticker := time.NewTicker(5 * time.Second)
+		defer ticker.Stop()
+		sample := func() {
+			var m runtime.MemStats
+			runtime.ReadMemStats(&m)
+			_ = json.NewEncoder(memory).Encode(struct {
+				At                                      time.Time
+				HeapAlloc, HeapObjects, TotalAlloc, Sys uint64
+				NumGC                                   uint32
+				Goroutines                              int
+			}{time.Now(), m.HeapAlloc, m.HeapObjects, m.TotalAlloc, m.Sys, m.NumGC, runtime.NumGoroutine()})
+		}
+		sample()
+		for {
+			select {
+			case <-ticker.C:
+				sample()
+			case <-done:
+				sample()
+				return
+			}
+		}
+	}()
 	var once sync.Once
 	stop := func() {
 		once.Do(func() {
 			pprof.StopCPUProfile()
+			close(done)
+			<-sampled
 			f.Close()
 			pprof.Lookup("allocs").WriteTo(alloc, 0)
 			alloc.Close()
+			if heap, err := os.Create(path + ".heap"); err == nil {
+				runtime.GC()
+				_ = pprof.WriteHeapProfile(heap)
+				_ = heap.Close()
+			}
 		})
 	}
 	t := time.AfterFunc(d, stop)

internal/cli/collect_profile_test.go

@@ -33,6 +33,12 @@ func TestCPUProfileStopsAfterDuration(t *testing.T) {
 		}
 		time.Sleep(10 * time.Millisecond)
 	}
+	stop()
+	for _, suffix := range []string{".heap", ".mem.jsonl"} {
+		if fi, err := os.Stat(path + suffix); err != nil || fi.Size() == 0 {
+			t.Fatalf("missing %s: %v", suffix, err)
+		}
+	}
 	// A second profile can start, so the first one released the profiler.
 	again, err := startCPUProfile(filepath.Join(t.TempDir(), "again.pprof"), time.Hour)
 	if err != nil {

internal/cli/command_tree_test.go

@@ -22,7 +22,7 @@ func parseCommand(t *testing.T, args ...string) (*Root, *kong.Context, error) {
 }
 func TestCommandTree(t *testing.T) {
 	paths := []string{
-		"", "summary", "flow", "flow 12", "agents", "agents list", "agents show 12", "agents jump 12", "agents kill 12", "projects", "projects list", "projects show app", "projects summarize app other", "projects summarize --all", "inbox", "inbox list", "inbox ack item", "inbox ack --all", "inbox jump item", "orphans", "orphans list", "orphans kill item", "orphans kill --all", "machines", "machines list", "machines show", "machines show local", "machines reset-id", "cleanup", "cleanup list", "cleanup remove item", "cleanup remove --all --kind worktree", "top", "app", "ask what needs me", "mcp", "doctor", "init", "config path", "config show", "config edit", "service run", "service run --serve --listen 127.0.0.1:7411", "service run --scheduled --service-data-dir fixture --service-env DRIGA_CAPTURE_TEXT=titles", "service install", "service start", "service stop", "service restart", "service status", "service logs -f", "service uninstall", "hooks install", "hooks install claude", "hooks uninstall codex", "hooks status", "hooks status all", "fleet peers list", "fleet peers add host:7411 --device-id device -y", "fleet peers remove peer", "fleet viewers list", "fleet viewers revoke viewer", "fleet enroll --allow-viewer viewer --allow-ack -y", "fleet rekey", "fleet id", "fleet status", "version", "hook claude Stop", "feed tail --after-seq 1 -f", "dev agy-schema", "mcp --chat", "mcp --snapshot",
+		"", "summary", "flow", "flow 12", "agents", "agents list", "agents show 12", "agents jump 12", "agents kill 12", "projects", "projects list", "projects show app", "projects summarize app other", "projects summarize --all", "inbox", "inbox list", "inbox ack item", "inbox ack --all", "inbox jump item", "orphans", "orphans list", "orphans kill item", "orphans kill --all", "machines", "machines list", "machines show", "machines show local", "machines reset-id", "cleanup", "cleanup list", "cleanup remove item", "cleanup remove --all --kind worktree", "top", "app", "app --cpu-profile app.pprof --profile-for 1m", "dev serve --cpu-profile app.pprof --profile-for 1m", "ask what needs me", "mcp", "doctor", "init", "config path", "config show", "config edit", "service run", "service run --serve --listen 127.0.0.1:7411", "service run --scheduled --service-data-dir fixture --service-env DRIGA_CAPTURE_TEXT=titles", "service install", "service start", "service stop", "service restart", "service status", "service logs -f", "service uninstall", "hooks install", "hooks install claude", "hooks uninstall codex", "hooks status", "hooks status all", "fleet peers list", "fleet peers add host:7411 --device-id device -y", "fleet peers remove peer", "fleet viewers list", "fleet viewers revoke viewer", "fleet enroll --allow-viewer viewer --allow-ack -y", "fleet rekey", "fleet id", "fleet status", "version", "hook claude Stop", "feed tail --after-seq 1 -f", "dev agy-schema", "mcp --chat", "mcp --snapshot",
 	}
 	for _, path := range paths {
 		t.Run(path, func(t *testing.T) {

internal/cli/dev_serve.go

@@ -19,10 +19,20 @@ import (
 // dev). It is the app without its window: the same page, data, Chat and
 // actions, but no native dialogs, menus, tray or notifications.
 type DevServeCmd struct {
-	Addr string `default:"127.0.0.1:47801" help:"Loopback address to listen on."`
+	CPUProfile string        `name:"cpu-profile" type:"path" help:"Write a CPU profile of the app to this file."`
+	ProfileFor time.Duration `name:"profile-for" default:"2m" help:"How long --cpu-profile records before it stops."`
+	Addr       string        `default:"127.0.0.1:47801" help:"Loopback address to listen on."`
 }
 
 func (c DevServeCmd) Run(g *Globals) error {
+	if c.CPUProfile != "" {
+		stopProfile, err := startCPUProfile(c.CPUProfile, c.ProfileFor)
+		if err != nil {
+			return err
+		}
+		defer stopProfile()
+	}
+
 	host, _, err := net.SplitHostPort(c.Addr)
 	if err != nil {
 		return invalidUsage("--addr must be host:port")