feat(host_metrics source): Add additional cgroup memory metrics

changelog.d/add_active_and_inactive_cgroup_memory_metrics.feature.md

@@ -0,0 +1,3 @@
+Add active and inactive metrics for anon and file memory to the cgroup collector. These additional metrics allow you to better understand the existing cgroup memory metrics.
+
+authors: nionata

src/sources/host_metrics/cgroups.rs

@@ -177,6 +177,26 @@ impl<'a> CGroupRecurser<'a> {
                 .gauge("cgroup_memory_anon_bytes", stat.anon as f64, tags.clone());
             self.output
                 .gauge("cgroup_memory_file_bytes", stat.file as f64, tags.clone());
+            self.output.gauge(
+                "cgroup_memory_anon_active_bytes",
+                stat.active_anon as f64,
+                tags.clone(),
+            );
+            self.output.gauge(
+                "cgroup_memory_anon_inactive_bytes",
+                stat.inactive_anon as f64,
+                tags.clone(),
+            );
+            self.output.gauge(
+                "cgroup_memory_file_active_bytes",
+                stat.active_file as f64,
+                tags.clone(),
+            );
+            self.output.gauge(
+                "cgroup_memory_file_inactive_bytes",
+                stat.inactive_file as f64,
+                tags.clone(),
+            );
         }
     }
 }
@@ -389,6 +409,10 @@ define_stat_struct! { MemoryStat(
     // for more details.
     anon,
     file,
+    active_anon,
+    inactive_anon,
+    active_file,
+    inactive_file,
 )}
 
 fn is_dir(path: impl AsRef<Path>) -> bool {
@@ -469,6 +493,10 @@ mod tests {
         assert_ne!(count_name(&metrics, "cgroup_cpu_system_seconds_total"), 0);
         assert_ne!(count_name(&metrics, "cgroup_memory_anon_bytes"), 0);
         assert_ne!(count_name(&metrics, "cgroup_memory_file_bytes"), 0);
+        assert_ne!(count_name(&metrics, "cgroup_memory_anon_active_bytes"), 0);
+        assert_ne!(count_name(&metrics, "cgroup_memory_anon_inactive_bytes"), 0);
+        assert_ne!(count_name(&metrics, "cgroup_memory_file_active_bytes"), 0);
+        assert_ne!(count_name(&metrics, "cgroup_memory_file_inactive_bytes"), 0);
     }
 
     #[tokio::test]
@@ -601,6 +629,22 @@ mod tests {
                 count_name(&metrics, "cgroup_memory_file_bytes"),
                 SUBDIRS.len()
             );
+            assert_eq!(
+                count_name(&metrics, "cgroup_memory_anon_active_bytes"),
+                SUBDIRS.len()
+            );
+            assert_eq!(
+                count_name(&metrics, "cgroup_memory_anon_inactive_bytes"),
+                SUBDIRS.len()
+            );
+            assert_eq!(
+                count_name(&metrics, "cgroup_memory_file_active_bytes"),
+                SUBDIRS.len()
+            );
+            assert_eq!(
+                count_name(&metrics, "cgroup_memory_file_inactive_bytes"),
+                SUBDIRS.len()
+            );
         }
 
         fn group(&mut self, subdir: &str, flags: usize, controllers: Option<&str>) {

website/cue/reference/components/sources/host_metrics.cue

@@ -120,6 +120,10 @@ components: sources: host_metrics: {
 		cgroup_memory_current_bytes: _host & _cgroup_memory & {description: "The total amount of memory currently being used by this cgroup and its descendants, in bytes."}
 		cgroup_memory_anon_bytes: _host & _cgroup_memory & {description: "The total amount of memory used by this cgroup in anonymous mappings (normal program allocation), in bytes."}
 		cgroup_memory_file_bytes: _host & _cgroup_memory & {description: "The total amount of memory used by this cgroup to cache filesystem data, including tmpfs and shared memory, in bytes."}
+		cgroup_memory_anon_active_bytes: _host & _cgroup_memory & {description: "Amount of memory, swap-backed, on the internal memory management active lists used by the page reclaim algorithm, in bytes."}
+		cgroup_memory_anon_inactive_bytes: _host & _cgroup_memory & {description: "Amount of memory, swap-backed, on the internal memory management inactive lists used by the page reclaim algorithm, in bytes."}
+		cgroup_memory_file_active_bytes: _host & _cgroup_memory & {description: "Amount of memory, filesystem-backed, on the internal memory management active lists used by the page reclaim algorithm, in bytes."}
+		cgroup_memory_file_inactive_bytes: _host & _cgroup_memory & {description: "Amount of memory, filesystem-backed, on the internal memory management inactive lists used by the page reclaim algorithm, in bytes."}
 
 		// Host disk
 		disk_read_bytes_total: _host & _disk_counter & {description: "The accumulated number of bytes read in."}