From 574ba8ddd5753972305a2fc60f3cbad3f8085dda Mon Sep 17 00:00:00 2001
From: YC27 <76414902+YC27@users.noreply.github.com>
Date: Tue, 22 Oct 2024 18:03:36 +0800
Subject: [PATCH] Active Load: Adjust the default execution thread to match the
 number of CPU cores (#13865)

---
 .../org/apache/iotdb/db/conf/IoTDBConfig.java    |  2 +-
 .../apache/iotdb/db/conf/IoTDBDescriptor.java    | 16 ++++++----------
 .../conf/iotdb-system.properties.template        |  4 ++--
 3 files changed, 9 insertions(+), 13 deletions(-)

diff --git a/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/conf/IoTDBConfig.java b/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/conf/IoTDBConfig.java
index 2dddbd3318dd..eb046f03989d 100644
--- a/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/conf/IoTDBConfig.java
+++ b/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/conf/IoTDBConfig.java
@@ -1199,7 +1199,7 @@ public class IoTDBConfig {
 
   private long loadActiveListeningCheckIntervalSeconds = 5L;
 
-  private int loadActiveListeningMaxThreadNum = 8;
+  private int loadActiveListeningMaxThreadNum = Runtime.getRuntime().availableProcessors();
 
   /** Pipe related */
   /** initialized as empty, updated based on the latest `systemDir` during querying */
diff --git a/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/conf/IoTDBDescriptor.java b/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/conf/IoTDBDescriptor.java
index f45025a2ad01..3376a4132395 100644
--- a/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/conf/IoTDBDescriptor.java
+++ b/iotdb-core/datanode/src/main/java/org/apache/iotdb/db/conf/IoTDBDescriptor.java
@@ -2357,19 +2357,15 @@ private void loadLoadTsFileProps(Properties properties) {
             ? conf.getLoadActiveListeningCheckIntervalSeconds()
             : loadActiveListeningCheckIntervalSeconds);
 
-    final int defaultLoadActiveListeningMaxThreadNum =
-        Math.min(
-            conf.getLoadActiveListeningMaxThreadNum(),
-            Math.max(1, Runtime.getRuntime().availableProcessors() / 2));
-    final int loadActiveListeningMaxThreadNum =
+    conf.setLoadActiveListeningMaxThreadNum(
         Integer.parseInt(
             properties.getProperty(
                 "load_active_listening_max_thread_num",
-                Integer.toString(defaultLoadActiveListeningMaxThreadNum)));
-    conf.setLoadActiveListeningMaxThreadNum(
-        loadActiveListeningMaxThreadNum <= 0
-            ? defaultLoadActiveListeningMaxThreadNum
-            : loadActiveListeningMaxThreadNum);
+                Integer.toString(conf.getLoadActiveListeningMaxThreadNum()))));
+
+    if (conf.getLoadActiveListeningMaxThreadNum() <= 0) {
+      conf.setLoadActiveListeningMaxThreadNum(Runtime.getRuntime().availableProcessors());
+    }
   }
 
   private void loadLoadTsFileHotModifiedProp(Properties properties) throws IOException {
diff --git a/iotdb-core/node-commons/src/assembly/resources/conf/iotdb-system.properties.template b/iotdb-core/node-commons/src/assembly/resources/conf/iotdb-system.properties.template
index 5e61fa8926f3..531891e456da 100644
--- a/iotdb-core/node-commons/src/assembly/resources/conf/iotdb-system.properties.template
+++ b/iotdb-core/node-commons/src/assembly/resources/conf/iotdb-system.properties.template
@@ -1949,10 +1949,10 @@ load_active_listening_dirs=ext/load/pending
 load_active_listening_fail_dir=ext/load/failed
 
 # The maximum number of threads that can be used to load tsfile actively.
-# The default value, when this parameter is commented out, is the minimum of 8 or the number of CPU cores.
+# The default value, when this parameter is commented out or <= 0, use CPU core number.
 # effectiveMode: restart
 # Datatype: int
-load_active_listening_max_thread_num=8
+load_active_listening_max_thread_num=0
 
 # The interval specified in seconds for the active listening mode to check the directory specified in load_active_listening_dirs.
 # The active listening mode will check the directory every load_active_listening_check_interval_seconds seconds.