Memory (macOS): Refines Memory usage detection on macOS to match Activity Monitor more closely

Author: CarterLi

CHANGELOG.md

@@ -4,8 +4,8 @@ Features:
 * Improves compatibility with KDE Plasma 6.5 (#2093, Display)
 * Adds a `tempSensor` option to specify the sensor name used for CPU temperature detection (CPU)
     * Example: `{ "type": "cpu", "tempSensor": "hwmon0" /* Use /sys/class/hwmon/hwmon0 for temperature detection */ }`
+* Refines Memory usage detection on macOS to match Activity Monitor more closely (Memory, macOS)
 * Minor optimizations
-* Reports usable RAM size to match other platforms (Memory, macOS)
 
 Bugfixes:
 * Fixes cache line size detection (CPU, macOS)

src/detection/memory/memory_apple.c

@@ -8,27 +8,25 @@
 const char* ffDetectMemory(FFMemoryResult* ram)
 {
     size_t length = sizeof(ram->bytesTotal);
-    if (sysctlbyname("hw.memsize_usable", &ram->bytesTotal, &length, NULL, 0) != 0)
-    {
-        if (sysctl((int[]){ CTL_HW, HW_MEMSIZE }, 2, &ram->bytesTotal, &length, NULL, 0) != 0)
-            return "Failed to read hw.memsize";
-    }
+    if (sysctl((int[]){ CTL_HW, HW_MEMSIZE }, 2, &ram->bytesTotal, &length, NULL, 0) != 0)
+        return "Failed to read hw.memsize";
+    uint64_t usableMemory = 0;
+    length = sizeof(usableMemory);
+    if (sysctlbyname("hw.memsize_usable", &usableMemory, &length, NULL, 0) != 0)
+        usableMemory = ram->bytesTotal;
 
     mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
     vm_statistics64_data_t vmstat;
     if(host_statistics64(mach_host_self(), HOST_VM_INFO64, (host_info64_t) (&vmstat), &count) != KERN_SUCCESS)
         return "Failed to read host_statistics64";
 
-    // https://github.com/exelban/stats/blob/master/Modules/RAM/readers.swift#L56
-    ram->bytesUsed = ((uint64_t)
-        + vmstat.active_count
-        + vmstat.inactive_count
-        + vmstat.speculative_count
-        + vmstat.wire_count
-        + vmstat.compressor_page_count
-        - vmstat.purgeable_count
-        - vmstat.external_page_count
-    ) * instance.state.platform.sysinfo.pageSize;
+    uint64_t pageSize = instance.state.platform.sysinfo.pageSize;
+    uint64_t appMemory = vmstat.internal_page_count * pageSize;
+    uint64_t wiredMemory = vmstat.wire_count * pageSize;
+    uint64_t compressed = vmstat.compressor_page_count * pageSize;
+    uint64_t reserved = ram->bytesTotal - usableMemory;
+
+    ram->bytesUsed = appMemory + wiredMemory + compressed + reserved;
 
     return NULL;
 }