From 1a774eb76c1fdb613bc1af8bf70e96a98e85ba79 Mon Sep 17 00:00:00 2001
From: Geoffroy Couprie <apollo@geoffroycouprie.com>
Date: Tue, 6 Aug 2024 16:41:15 +0200
Subject: [PATCH] get heap statistics from deno

---
 router-bridge/js-src/plan_worker.ts | 53 ++++++++++++++++++++++++++++-
 router-bridge/src/planner.rs        | 31 +++++++++++++++++
 2 files changed, 83 insertions(+), 1 deletion(-)

diff --git a/router-bridge/js-src/plan_worker.ts b/router-bridge/js-src/plan_worker.ts
index 23b72407e..0be826b8c 100644
--- a/router-bridge/js-src/plan_worker.ts
+++ b/router-bridge/js-src/plan_worker.ts
@@ -24,6 +24,19 @@ declare let logger: {
   error: typeof logFunction;
 };
 
+export interface MemoryUsage {
+  /** The number of bytes of the current Deno's process resident set size,
+   * which is the amount of memory occupied in main memory (RAM). */
+  rss: number;
+  /** The total size of the heap for V8, in bytes. */
+  heapTotal: number;
+  /** The amount of the heap used for V8, in bytes. */
+  heapUsed: number;
+  /** Memory, in bytes, associated with JavaScript objects outside of the
+   * JavaScript isolate. */
+  external: number;
+}
+
 enum PlannerEventKind {
   UpdateSchema = "UpdateSchema",
   Plan = "Plan",
@@ -32,6 +45,7 @@ enum PlannerEventKind {
   Introspect = "Introspect",
   Signature = "Signature",
   Subgraphs = "Subgraphs",
+  GetHeapStatistics = "GetHeapStatistics",
 }
 
 interface UpdateSchemaEvent {
@@ -75,6 +89,11 @@ interface Exit {
   kind: PlannerEventKind.Exit;
   schemaId: number;
 }
+
+interface GetHeapStatisticsEvent {
+  kind: PlannerEventKind.GetHeapStatistics;
+}
+
 type PlannerEvent =
   | UpdateSchemaEvent
   | PlanEvent
@@ -82,6 +101,7 @@ type PlannerEvent =
   | IntrospectEvent
   | SignatureEvent
   | SubgraphsEvent
+  | GetHeapStatisticsEvent
   | Exit;
 type PlannerEventWithId = {
   id: string;
@@ -92,12 +112,14 @@ type WorkerResultWithId = {
   id?: string;
   payload: WorkerResult;
 };
+
 type WorkerResult =
   | PlanResult
   | ApiSchemaResult
   | ExecutionResult
   | Map<string, string>
-  | String;
+  | String
+  | MemoryUsageResult;
 // Plan result
 type PlanResult =
   | ExecutionResultWithUsageReporting<QueryPlanResult>
@@ -105,6 +127,12 @@ type PlanResult =
 type ApiSchemaResult = {
   schema: string;
 };
+type MemoryUsageResult = {
+  rss: number;
+  heapTotal: number;
+  heapUsed: number;
+  external: number;
+};
 
 type FatalError = {
   errors: (JsError | WorkerGraphQLError)[];
@@ -290,6 +318,29 @@ async function run() {
 
             await send({ id, payload: subgraphs });
             break;
+          case PlannerEventKind.GetHeapStatistics:
+            logger.info(`received event: ${JSON.stringify(event)}`);
+
+            const mem = Deno.memoryUsage();
+            //const mem = memoryUsage();
+
+            logger.info(`got memoryUsage`);
+            const result: MemoryUsageResult = {
+              rss: mem.rss,
+              heapTotal: mem.heapTotal,
+              heapUsed: mem.heapUsed,
+              external: mem.external,
+            };
+            /*const result: MemoryUsageResult = {
+              rss: 1,
+              heapTotal: 2,
+              heapUsed: 3,
+              external: 4,
+            };*/
+            logger.info(`memoryUsage: ${JSON.stringify(result)}`);
+
+            await send({ id, payload: result });
+            break;
           case PlannerEventKind.Exit:
             planners.delete(event.schemaId);
             if (planners.size == 0) {
diff --git a/router-bridge/src/planner.rs b/router-bridge/src/planner.rs
index 5bdc08fbc..941acae3f 100644
--- a/router-bridge/src/planner.rs
+++ b/router-bridge/src/planner.rs
@@ -398,6 +398,15 @@ where
     }
 }
 
+#[derive(Deserialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct HeapStatistics {
+    pub rss: u64,
+    pub heap_total: u64,
+    pub heap_used: u64,
+    pub external: u64,
+}
+
 /// A Deno worker backed query Planner.
 
 pub struct Planner<T>
@@ -586,6 +595,11 @@ where
             })
             .await
     }
+
+    /// Get deno's heap statistics
+    pub async fn get_heap_statistics(&self) -> Result<HeapStatistics, crate::error::Error> {
+        self.worker.request(PlanCmd::GetHeapStatistics).await
+    }
 }
 
 impl<T> Drop for Planner<T>
@@ -647,7 +661,10 @@ enum PlanCmd {
     Subgraphs { schema_id: u64 },
     #[serde(rename_all = "camelCase")]
     Exit { schema_id: u64 },
+    #[serde(rename_all = "camelCase")]
+    GetHeapStatistics,
 }
+
 #[derive(Serialize, Debug, Clone, PartialEq, Eq, Hash)]
 #[serde(rename_all = "camelCase")]
 /// Query planner configuration
@@ -1871,6 +1888,20 @@ ofType {
             insta::assert_snapshot!(schema);
         }
     }
+
+    #[tokio::test]
+    async fn heap_statistics() {
+        let planner =
+            Planner::<serde_json::Value>::new(SCHEMA.to_string(), QueryPlannerConfig::default())
+                .await
+                .unwrap();
+
+        let _subgraphs = planner.subgraphs().await.unwrap();
+        let statistics = planner.get_heap_statistics().await.unwrap();
+
+        println!("statistics: {statistics:?}");
+        panic!()
+    }
 }
 
 #[cfg(test)]