S1 #11: the System App: tasks, memory, network and system, live

Five views, Tab between them: Overview (each core's load, memory,
traffic, battery, two minutes of load), Tasks (share of a core over the
last second, lowest free stack, flagged under 512 bytes; `s` sorts),
Memory (free heap against the floors of Q86), Network (bytes per
service, and what's moving now), System (what `info` prints, plus
battery, card, radio, GNSS). It samples once a second and keeps history
only while open.

The arithmetic is host-tested, including the trap found on the device: a
task's run-time counter only moves when it's switched out, so the task
that samples (the main loop, alone on its core) gets what's left of its
core. `tasks` now samples across a second of normal running instead of
inside its own wait. The main loop uses 100 % of core 1 at rest (#40).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EhqxQ49eCju4CzKYNjZzwT

src/platform/system_info.cpp

@@ -7,6 +7,8 @@
 #include <freertos/FreeRTOS.h>
 #include <freertos/task.h>
 
+#include <algorithm>
+#include <cstdio>
 #include <string>
 #include <vector>
 
@@ -89,20 +91,40 @@ void printSlots(Print& out, KeyValueStore& store) {
     }
 }
 
-void printTasks(Print& out) {
+uint32_t sampleTasks(std::vector<TaskSample>& out) {
     UBaseType_t n = uxTaskGetNumberOfTasks();
     std::vector<TaskStatus_t> tasks(n + 4);
     uint32_t total = 0;
     n = uxTaskGetSystemState(tasks.data(), tasks.size(), &total);
-    out.printf("%-16s %-4s %3s %6s %5s %s\n", "task", "st", "pri", "stack", "cpu%", "core");
-    static const char kStates[] = "RrBSD";  // running, ready, blocked, suspended, deleted
+    out.clear();
+    out.reserve(n);
     for (UBaseType_t i = 0; i < n; i++) {
         const TaskStatus_t& t = tasks[i];
-        unsigned cpu = total ? (unsigned)((uint64_t)t.ulRunTimeCounter * 100 / total) : 0;
-        int core = t.xCoreID == tskNO_AFFINITY ? -1 : (int)t.xCoreID;
-        out.printf("%-16s %-4c %3u %6u %5u %d\n", t.pcTaskName, t.eCurrentState < 5 ? kStates[t.eCurrentState] : '?',
-                   (unsigned)t.uxCurrentPriority, (unsigned)t.usStackHighWaterMark, cpu, core);
+        TaskSample s;
+        s.id = t.xTaskNumber;
+        std::snprintf(s.name, sizeof s.name, "%s", t.pcTaskName);
+        s.runtime = t.ulRunTimeCounter;
+        s.stackFree = static_cast<uint16_t>(std::min<uint32_t>(t.usStackHighWaterMark, 0xFFFF));
+        s.core = t.xCoreID == tskNO_AFFINITY ? -1 : static_cast<int8_t>(t.xCoreID);
+        s.state = static_cast<uint8_t>(t.eCurrentState);
+        s.priority = static_cast<uint8_t>(t.uxCurrentPriority);
+        out.push_back(s);
     }
+    return total;
+}
+
+// Shares over the interval since `before`, not since boot: the counters wrap every 71 minutes.
+void printTasks(Print& out, const std::vector<TaskSample>& before, uint32_t beforeTotal) {
+    std::vector<TaskSample> now;
+    uint32_t t1 = sampleTasks(now);
+    std::vector<TaskRow> rows = taskRows(before, beforeTotal, now, t1);
+    sortTasks(rows, TaskSort::Share);
+    out.printf("%-16s %-4s %3s %6s %6s %s\n", "task", "st", "pri", "stack", "cpu%", "core");
+    static const char kStates[] = "RrBSD";  // running, ready, blocked, suspended, deleted
+    for (const TaskRow& r : rows)
+        out.printf("%-16s %-4c %3u %6u %4u.%u %d%s\n", r.name.c_str(), r.state < 5 ? kStates[r.state] : '?', r.priority,
+                   r.stackFree, r.permille / 10, r.permille % 10, r.core, r.lowStack ? "  low stack" : "");
+    out.printf("load: core 0 %d %%, core 1 %d %%\n", coreLoad(rows, 0), coreLoad(rows, 1));
 }
 
 const char* bootOtherSlot() {

src/platform/system_info.h

@@ -3,7 +3,10 @@
 #include <Print.h>
 #include <esp_partition.h>
 
+#include <vector>
+
 #include "key_value_store.h"
+#include "task_stats.h"
 
 namespace roro::system_info {
 
@@ -20,7 +23,12 @@ void printSlots(Print& out, KeyValueStore& store);
 // Remembers which version the running slot holds (call at boot), or the slot an update just wrote.
 void recordSlotVersion(KeyValueStore& store, const esp_partition_t* slot, const char* version);
 // FreeRTOS tasks: state, priority, lowest free stack, CPU share since boot.
-void printTasks(Print& out);
+// The tasks' shares since `before` was sampled (with its run-time clock). The caller lets the main
+// loop run in between: sampling twice inside one command would show the loop asleep.
+void printTasks(Print& out, const std::vector<TaskSample>& before, uint32_t beforeTotal);
+// Every task as FreeRTOS reports it now; returns the run-time clock (microseconds, 32 bits), to
+// pair with the samples. Two of these make the shares the System App and `tasks` show.
+uint32_t sampleTasks(std::vector<TaskSample>& out);
 
 // Boots the firmware in the other app slot if it holds a valid image (a manual Rollback).
 // Returns an error message; on success it restarts and doesn't return.