Introduce jemalloc-allocator feature flag (#6675)

* Introduce jemalloc-stats feature flag

* remove unneeded space

* Update node/overseer/src/lib.rs

Co-authored-by: Marcin S. <marcin@bytedude.com>

* Update Cargo.toml

Co-authored-by: Marcin S. <marcin@bytedude.com>

* revert making tikv-jemallocator depend on jemalloc-stats

* conditionally import memory_stats instead of using dead_code

* fix test via expllicit import

* Add jemalloc-stats feature to crates, propagate it from root

* Apply `jemalloc-stats` feature to prepare mem stats; small refactor

* effect changes recommended on PR

* Update node/overseer/src/metrics.rs

Co-authored-by: Marcin S. <marcin@bytedude.com>

* fix compile error on in pipeline for linux. missing import

* Update node/overseer/src/lib.rs

Co-authored-by: Bastian Köcher <git@kchr.de>

* revert to defining collect_memory_stats inline

---------

Co-authored-by: Marcin S. <marcin@bytedude.com>
Co-authored-by: Marcin S <marcin@realemail.net>
Co-authored-by: Bastian Köcher <git@kchr.de>

polkadot/node/overseer/src/lib.rs

@@ -117,14 +117,13 @@ pub const KNOWN_LEAVES_CACHE_SIZE: NonZeroUsize = match NonZeroUsize::new(2 * 24
 	None => panic!("Known leaves cache size must be non-zero"),
 };
 
+#[cfg(any(target_os = "linux", feature = "jemalloc-allocator"))]
 mod memory_stats;
 #[cfg(test)]
 mod tests;
 
 use sp_core::traits::SpawnNamed;
 
-use memory_stats::MemoryAllocationTracker;
-
 /// Glue to connect `trait orchestra::Spawner` and `SpawnNamed` from `substrate`.
 pub struct SpawnGlue<S>(pub S);
 
@@ -654,8 +653,9 @@ where
 	}
 	let subsystem_meters = overseer.map_subsystems(ExtractNameAndMeters);
 
+	#[cfg(any(target_os = "linux", feature = "jemalloc-allocator"))]
 	let collect_memory_stats: Box<dyn Fn(&OverseerMetrics) + Send> =
-		match MemoryAllocationTracker::new() {
+		match memory_stats::MemoryAllocationTracker::new() {
 			Ok(memory_stats) =>
 				Box::new(move |metrics: &OverseerMetrics| match memory_stats.snapshot() {
 					Ok(memory_stats_snapshot) => {
@@ -679,6 +679,9 @@ where
 			},
 		};
 
+	#[cfg(not(any(target_os = "linux", feature = "jemalloc-allocator")))]
+	let collect_memory_stats: Box<dyn Fn(&OverseerMetrics) + Send> = Box::new(|_| {});
+
 	let metronome = Metronome::new(std::time::Duration::from_millis(950)).for_each(move |_| {
 		collect_memory_stats(&metronome_metrics);
 

polkadot/node/overseer/src/memory_stats.rs

@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.
 
-use tikv_jemalloc_ctl::{epoch, stats, Error};
+use tikv_jemalloc_ctl::stats;
 
 #[derive(Clone)]
 pub struct MemoryAllocationTracker {
@@ -24,15 +24,15 @@ pub struct MemoryAllocationTracker {
 }
 
 impl MemoryAllocationTracker {
-	pub fn new() -> Result<Self, Error> {
+	pub fn new() -> Result<Self, tikv_jemalloc_ctl::Error> {
 		Ok(Self {
-			epoch: epoch::mib()?,
+			epoch: tikv_jemalloc_ctl::epoch::mib()?,
 			allocated: stats::allocated::mib()?,
 			resident: stats::resident::mib()?,
 		})
 	}
 
-	pub fn snapshot(&self) -> Result<MemoryAllocationSnapshot, Error> {
+	pub fn snapshot(&self) -> Result<MemoryAllocationSnapshot, tikv_jemalloc_ctl::Error> {
 		// update stats by advancing the allocation epoch
 		self.epoch.advance()?;
 

polkadot/node/overseer/src/metrics.rs

@@ -19,8 +19,6 @@
 use super::*;
 pub use polkadot_node_metrics::metrics::{self, prometheus, Metrics as MetricsTrait};
 
-use memory_stats::MemoryAllocationSnapshot;
-
 /// Overseer Prometheus metrics.
 #[derive(Clone)]
 struct MetricsInner {
@@ -40,7 +38,9 @@ struct MetricsInner {
 	signals_sent: prometheus::GaugeVec<prometheus::U64>,
 	signals_received: prometheus::GaugeVec<prometheus::U64>,
 
+	#[cfg(any(target_os = "linux", feature = "jemalloc-allocator"))]
 	memory_stats_resident: prometheus::Gauge<prometheus::U64>,
+	#[cfg(any(target_os = "linux", feature = "jemalloc-allocator"))]
 	memory_stats_allocated: prometheus::Gauge<prometheus::U64>,
 }
 
@@ -67,7 +67,11 @@ impl Metrics {
 		}
 	}
 
-	pub(crate) fn memory_stats_snapshot(&self, memory_stats: MemoryAllocationSnapshot) {
+	#[cfg(any(target_os = "linux", feature = "jemalloc-allocator"))]
+	pub(crate) fn memory_stats_snapshot(
+		&self,
+		memory_stats: memory_stats::MemoryAllocationSnapshot,
+	) {
 		if let Some(metrics) = &self.0 {
 			metrics.memory_stats_allocated.set(memory_stats.allocated as u64);
 			metrics.memory_stats_resident.set(memory_stats.resident as u64);
@@ -246,7 +250,7 @@ impl MetricsTrait for Metrics {
 				)?,
 				registry,
 			)?,
-
+			#[cfg(any(target_os = "linux", feature = "jemalloc-allocator"))]
 			memory_stats_allocated: prometheus::register(
 				prometheus::Gauge::<prometheus::U64>::new(
 					"polkadot_memory_allocated",
@@ -254,6 +258,7 @@ impl MetricsTrait for Metrics {
 				)?,
 				registry,
 			)?,
+			#[cfg(any(target_os = "linux", feature = "jemalloc-allocator"))]
 			memory_stats_resident: prometheus::register(
 				prometheus::Gauge::<prometheus::U64>::new(
 					"polkadot_memory_resident",