From 49d4b81d97c7c75778eab09a58a10bcd71f0fde1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Aur=C3=A9lien=20Boquet?= <aurelien.boquet.web@gmail.com>
Date: Thu, 24 Aug 2023 12:19:38 +0200
Subject: [PATCH 1/3] Improve ObjectId serialization by around 10%

---
 etc/benchmarks/main.mjs  | 20 +++++++++++++++++++-
 src/parser/serializer.ts | 10 +++++++---
 2 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/etc/benchmarks/main.mjs b/etc/benchmarks/main.mjs
index 6f48cb1f..6635efc1 100644
--- a/etc/benchmarks/main.mjs
+++ b/etc/benchmarks/main.mjs
@@ -25,6 +25,24 @@ await runner({
     bson.lib.deserialize(documents[i], { validation: { utf8: false } });
   }
 });
+
+await runner({
+  skip: false,
+  name: 'serialize an ObjectId',
+  iterations,
+  setup(libs) {
+    const bson = getCurrentLocalBSON(libs);
+    return Array.from({ length: 100000 }, () => ({
+      _id: new bson.lib.ObjectId()
+    }));
+  },
+  run(i, bson, documents) {
+    bson.lib.serialize({
+      nextBatch: documents
+    });
+  }
+});
+
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 await runner({
   skip: true,
@@ -102,7 +120,7 @@ await runner({
 /// nextBatch simulate
 /// nextBatch: [ { string * 20 } * 1000 ] /// Garbage call
 await runner({
-  skip: false,
+  skip: true,
   name: 'deserialize a large batch of documents each with an array of many strings',
   iterations,
   setup(libs) {
diff --git a/src/parser/serializer.ts b/src/parser/serializer.ts
index 6f75cb0a..f5f56226 100644
--- a/src/parser/serializer.ts
+++ b/src/parser/serializer.ts
@@ -257,14 +257,18 @@ function serializeObjectId(buffer: Uint8Array, key: string, value: ObjectId, ind
   buffer[index++] = 0;
 
   // Write the objectId into the shared buffer
-  if (isUint8Array(value.id)) {
-    buffer.set(value.id.subarray(0, 12), index);
+  const idValue = value.id;
+
+  if (isUint8Array(idValue)) {
+    for (let i = 0; i < 12; i++) {
+      buffer[index++] = idValue[i];
+    }
   } else {
     throw new BSONError('object [' + JSON.stringify(value) + '] is not a valid ObjectId');
   }
 
   // Adjust index
-  return index + 12;
+  return index;
 }
 
 function serializeBuffer(buffer: Uint8Array, key: string, value: Uint8Array, index: number) {

From 488cacc9083bde54d918dfb0ded12fdb48474b47 Mon Sep 17 00:00:00 2001
From: Warren James <warren.james@mongodb.com>
Date: Tue, 5 Sep 2023 13:24:26 -0400
Subject: [PATCH 2/3] test(NODE-5577): Migrate benchmark to new format

---
 test/bench/src/index.ts                       |  3 ++-
 .../src/suites/objectid_serialization.ts      | 24 +++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)
 create mode 100644 test/bench/src/suites/objectid_serialization.ts

diff --git a/test/bench/src/index.ts b/test/bench/src/index.ts
index 2de638aa..81103404 100644
--- a/test/bench/src/index.ts
+++ b/test/bench/src/index.ts
@@ -1,4 +1,5 @@
 import { getStringDeserializationSuite } from './suites/string_deserialization';
+import { getObjectIdSerializationSuite } from './suites/objectid_serialization';
 import { type PerfSendData } from './util';
 import { writeFile } from 'fs';
 import { cpus, totalmem } from 'os';
@@ -17,7 +18,7 @@ console.log(
   ].join('\n')
 );
 
-for (const suite of [getStringDeserializationSuite()]) {
+for (const suite of [getStringDeserializationSuite(), getObjectIdSerializationSuite()]) {
   suite.run();
   results.push(suite.results);
 }
diff --git a/test/bench/src/suites/objectid_serialization.ts b/test/bench/src/suites/objectid_serialization.ts
new file mode 100644
index 00000000..ef62301e
--- /dev/null
+++ b/test/bench/src/suites/objectid_serialization.ts
@@ -0,0 +1,24 @@
+import { Suite } from '../suite';
+import * as BSON from '../../../../';
+
+export function getObjectIdSerializationSuite(): Suite {
+  const suite = new Suite('objectid serialization');
+  const data = {
+    docs: Array.from({ length: 1_000 }, () => new BSON.ObjectId())
+  };
+
+  suite.task({
+    name: 'ObjectId serialization',
+    data,
+    fn: objectIds => {
+      BSON.serialize(objectIds);
+    },
+    iterations: 10_000,
+    resultUnit: 'megabytes_per_second',
+    transform: (runtimeMS: number) => {
+      return BSON.calculateObjectSize(data) / 1024 ** 2 / (runtimeMS / 1000);
+    }
+  });
+
+  return suite;
+}

From 414745f26b06fc325d9559832efb075738a1ec6f Mon Sep 17 00:00:00 2001
From: Warren James <warren.james@mongodb.com>
Date: Tue, 5 Sep 2023 13:31:05 -0400
Subject: [PATCH 3/3] test(NODE-5577): remove user benchmark

---
 etc/benchmarks/main.mjs | 20 +-------------------
 1 file changed, 1 insertion(+), 19 deletions(-)

diff --git a/etc/benchmarks/main.mjs b/etc/benchmarks/main.mjs
index 6635efc1..6f48cb1f 100644
--- a/etc/benchmarks/main.mjs
+++ b/etc/benchmarks/main.mjs
@@ -25,24 +25,6 @@ await runner({
     bson.lib.deserialize(documents[i], { validation: { utf8: false } });
   }
 });
-
-await runner({
-  skip: false,
-  name: 'serialize an ObjectId',
-  iterations,
-  setup(libs) {
-    const bson = getCurrentLocalBSON(libs);
-    return Array.from({ length: 100000 }, () => ({
-      _id: new bson.lib.ObjectId()
-    }));
-  },
-  run(i, bson, documents) {
-    bson.lib.serialize({
-      nextBatch: documents
-    });
-  }
-});
-
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 await runner({
   skip: true,
@@ -120,7 +102,7 @@ await runner({
 /// nextBatch simulate
 /// nextBatch: [ { string * 20 } * 1000 ] /// Garbage call
 await runner({
-  skip: true,
+  skip: false,
   name: 'deserialize a large batch of documents each with an array of many strings',
   iterations,
   setup(libs) {