fix(perf): review findings in the service and the panel

- The panel loads only while open. Its models are fresh arrays every
  sample, so a hidden instance rebuilt its rows every 2s for the whole
  session.
- The public IP fetch never kills one already running, and waits 30
  minutes from the last attempt, not the last success: a rate-limited
  or offline fetch was retried every minute.
- curl -4, so an IPv6 answer cannot silently stall the VPN check.
- CPU load sums only the first eight /proc/stat fields. guest and
  guest_nice are already inside user and nice, and counting them again
  read high while VMs ran.
- df gets timeout -k; the VRAM scan is not restarted over itself.
- The GPU name joins the host constants in Perf.qml.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

5 files changed, 26 insertions, 16 deletions

diff --git a/desktop/island/StatusPill.qml b/desktop/island/StatusPill.qml
index dd97855..d62b87f 100644
--- a/desktop/island/StatusPill.qml
+++ b/desktop/island/StatusPill.qml
@@ -42,7 +42,7 @@ Capsule {
     restWidth: restRow.implicitWidth + 24
     panelWidth: panel === "perf" ? 600 : 320
     panelHeight: (panel === "controls" ? controlsPanel.implicitHeight
-                : panel === "perf" ? perfPanel.implicitHeight
+                : panel === "perf" ? (perfPanel.item ? perfPanel.item.implicitHeight : 0)
                 : soundPanel.implicitHeight) + 28
 
     // The detailed sampling (per-core, network, VRAM) runs only while the
@@ -191,13 +191,14 @@ Capsule {
         onOpenDrawer: page => pill.openPage(page)
     }
 
-    PerfPanel {
+    // Loaded only while open: its models are fresh arrays every sample, and
+    // a hidden instance would rebuild its rows every 2s for the whole session.
+    Loader {
         id: perfPanel
         x: 14
         y: 14
         width: 600 - 28
-        opacity: pill.panel === "perf" ? 1 : 0
-        visible: opacity > 0
-        Behavior on opacity { NumberAnimation { duration: 160 } }
+        active: pill.panel === "perf"
+        sourceComponent: PerfPanel { width: 600 - 28 }
     }
 }
diff --git a/desktop/island/perf/Perf.js b/desktop/island/perf/Perf.js
index d23d900..b853f50 100644
--- a/desktop/island/perf/Perf.js
+++ b/desktop/island/perf/Perf.js
@@ -23,7 +23,9 @@ const UNITS = { "": 1, B: 1, KiB: 1024, MiB: 1024 ** 2, GiB: 1024 ** 3 };
 const STALE = 4 * 3600;
 
 // One {total, idle} per cpu line of /proc/stat; index 0 is the aggregate,
-// then the cores in file order. idle counts iowait, as conky did.
+// then the cores in file order. idle counts iowait, as conky did. Only the
+// first eight fields are summed: guest and guest_nice are already inside
+// user and nice, and adding them again overstates load while VMs run.
 function cpuTimes(stat) {
     const out = [];
     for (const line of stat.split("\n")) {
@@ -31,7 +33,7 @@ function cpuTimes(stat) {
         if (!m) continue;
         const v = m[1].trim().split(/\s+/).map(Number);
         if (v.length < 5) continue;
-        out.push({ total: v.reduce((a, b) => a + b, 0), idle: v[3] + v[4] });
+        out.push({ total: v.slice(0, 8).reduce((a, b) => a + b, 0), idle: v[3] + v[4] });
     }
     return out;
 }
diff --git a/desktop/island/perf/Perf.qml b/desktop/island/perf/Perf.qml
index c2843f6..3153cec 100644
--- a/desktop/island/perf/Perf.qml
+++ b/desktop/island/perf/Perf.qml
@@ -36,6 +36,7 @@ Singleton {
     readonly property var mounts: ["/", "/home", "/data", "/mnt/nfs/Library", "/mnt/nfs/shared"]
     readonly property string iface: "br0"
     readonly property real vramTotal: 12 * 1024 * 1024 * 1024
+    readonly property string gpuName: "ARC B580"
 
     // Conky's table. Ceilings are per sensor: 70C is unremarkable on a CPU
     // package and alarming on an NVMe. GPU and VRAM are the GPU card's; the
@@ -86,15 +87,21 @@ Singleton {
         return isNaN(v) ? null : v;
     }
 
+    // Measured from the last attempt, not the last success, so a failing
+    // fetch (rate limited, offline) still waits 30 minutes; and never over
+    // one already running, which would kill it before it could answer.
+    property real pubAttempt: 0
     function fetchPubip() {
-        pubProc.running = false;
+        const now = Date.now() / 1000;
+        if (pubProc.running || !P.due(root.pub, now, 1800) || now - root.pubAttempt < 1800) return;
+        root.pubAttempt = now;
         pubProc.running = true;
     }
 
     onDetailedChanged: {
         if (detailed) {
             if (!root.lan) lanProc.running = true;
-            if (P.due(root.pub, Date.now() / 1000, 1800)) root.fetchPubip();
+            root.fetchPubip();
         } else {
             root.cores = [];
             root.rx = [];
@@ -189,8 +196,7 @@ Singleton {
 
             if (root.detailed) {
                 if (fanView.path) { fanView.reload(); root.fan = root.num(fanView); }
-                vramProc.running = false;
-                vramProc.running = true;
+                if (!vramProc.running) vramProc.running = true;
             }
         }
     }
@@ -247,7 +253,7 @@ Singleton {
 
     Process {
         id: dfProc
-        command: ["timeout", "5", "/usr/bin/df", "-P", "-B1"].concat(root.mounts)
+        command: ["timeout", "-k", "2", "5", "/usr/bin/df", "-P", "-B1"].concat(root.mounts)
         stdout: StdioCollector {
             onStreamFinished: {
                 const rows = P.df(text);
@@ -274,14 +280,14 @@ Singleton {
         interval: 60000
         running: true
         repeat: true
-        onTriggered: if (P.due(root.pub, Date.now() / 1000, 1800)) root.fetchPubip()
+        onTriggered: root.fetchPubip()
     }
 
     // Anything but an IPv4 address (a failure, an error page) leaves the
     // cache alone: the old value then goes stale rather than mismatching.
     Process {
         id: pubProc
-        command: ["curl", "-fsS", "--max-time", "10", "https://ipinfo.io/ip"]
+        command: ["curl", "-4fsS", "--max-time", "10", "https://ipinfo.io/ip"]
         stdout: StdioCollector {
             onStreamFinished: {
                 const ip = text.trim();
diff --git a/desktop/island/perf/PerfPanel.qml b/desktop/island/perf/PerfPanel.qml
index 5d3f6ff..5aad9b6 100644
--- a/desktop/island/perf/PerfPanel.qml
+++ b/desktop/island/perf/PerfPanel.qml
@@ -102,7 +102,6 @@ GridLayout {
         color: Qt.alpha(Theme.surface, 0.6)
         implicitHeight: body.implicitHeight + 20
         Layout.fillHeight: true
-        Layout.alignment: Qt.AlignTop
 
         Column {
             id: body
@@ -200,7 +199,7 @@ GridLayout {
         Layout.row: 0
         Layout.column: 1
         Layout.preferredWidth: panel.col
-        title: "GPU · ARC B580"
+        title: "GPU · " + Perf.gpuName
         headline: panel.deg(panel.gpuTemp.value)
         headlineColor: panel.tone(panel.gpuTemp.value, panel.gpuTemp.warn, panel.gpuTemp.crit)
 
diff --git a/desktop/island/perf/test_perf.js b/desktop/island/perf/test_perf.js
index c336cf0..5f39f5d 100644
--- a/desktop/island/perf/test_perf.js
+++ b/desktop/island/perf/test_perf.js
@@ -35,6 +35,8 @@ assert.strictEqual(t.length, 3);
 assert.deepStrictEqual(t[0], { total: 1000, idle: 850 });
 assert.deepStrictEqual(t[1], { total: 500, idle: 425 });
 assert.deepStrictEqual(P.cpuTimes(""), []);
+// guest and guest_nice are already inside user and nice: not added twice.
+assert.deepStrictEqual(P.cpuTimes("cpu  100 0 0 100 0 0 0 0 80 0"), [{ total: 200, idle: 100 }]);
 
 // load: busy share of the delta; no prev, or no time passed, is null.
 assert.strictEqual(P.load({ total: 1000, idle: 850 }, { total: 1100, idle: 925 }), 25);