#2640 (#2641)

Signed-off-by: Ngroot <yihua.mo@zilliz.com>

core/src/config/Config.cpp

@@ -863,6 +863,7 @@ Status
 Config::RegisterCallBack(const std::string& node, const std::string& sub_node, const std::string& key,
                          ConfigCallBackF& cb) {
     std::string cb_node = node + "." + sub_node;
+    std::lock_guard<std::mutex> lock(callback_mutex_);
     if (config_callback_.find(cb_node) == config_callback_.end()) {
         return Status(SERVER_UNEXPECTED_ERROR, cb_node + " is not supported changed in mem");
     }
@@ -875,6 +876,7 @@ Config::RegisterCallBack(const std::string& node, const std::string& sub_node, c
 
 Status
 Config::CancelCallBack(const std::string& node, const std::string& sub_node, const std::string& key) {
+    std::lock_guard<std::mutex> lock(callback_mutex_);
     if (config_callback_.empty() || key.empty()) {
         return Status::OK();
     }
@@ -1950,7 +1952,7 @@ Config::GetConfigVersion(std::string& value) {
 Status
 Config::ExecCallBacks(const std::string& node, const std::string& sub_node, const std::string& value) {
     auto status = Status::OK();
-
+    std::lock_guard<std::mutex> lock(callback_mutex_);
     if (config_callback_.empty()) {
         return Status(SERVER_UNEXPECTED_ERROR, "Callback map is empty. Cannot take effect in-service");
     }

core/src/config/Config.h

@@ -548,6 +548,7 @@ class Config {
     std::string config_file_;
     std::unordered_map<std::string, std::unordered_map<std::string, std::string>> config_map_;
     std::unordered_map<std::string, std::unordered_map<std::string, ConfigCallBackF>> config_callback_;
+    std::mutex callback_mutex_;
     std::mutex mutex_;
 };
 

core/unittest/server/test_config.cpp

@@ -11,6 +11,7 @@
 
 #include <cmath>
 #include <limits>
+#include <thread>
 
 #include <fiu-control.h>
 #include <fiu-local.h>
@@ -19,6 +20,7 @@
 
 #include "config/Config.h"
 #include "config/YamlConfigMgr.h"
+#include "config/handler/CacheConfigHandler.h"
 #include "server/utils.h"
 #include "utils/CommonUtil.h"
 #include "utils/StringHelpFunctions.h"
@@ -30,10 +32,42 @@ static constexpr uint64_t KB = 1024;
 static constexpr uint64_t MB = KB * 1024;
 static constexpr uint64_t GB = MB * 1024;
 
+class TestConfigHandler : public milvus::server::CacheConfigHandler {
+ public:
+    TestConfigHandler() {
+        SetIdentity("MemTableFile");
+        AddInsertBufferSizeListener();
+    }
+};
+
 }  // namespace
 
 namespace ms = milvus::server;
 
+TEST_F(ConfigTest, CONFIG_HANDLER_TEST) {
+    auto test_func = [&]() {
+        uint64_t count = 10000, index = 0;
+        while (true) {
+            if (index++ == count) {
+                break;
+            }
+
+            // register callback
+            TestConfigHandler ttt;
+
+            // trigger callback
+            auto& config = milvus::server::Config::GetInstance();
+            config.SetCacheConfigInsertBufferSize("1GB");
+        }
+    };
+
+    using ThreadPtr = std::shared_ptr<std::thread>;
+    ThreadPtr thread_1 = std::make_shared<std::thread>(test_func);
+    ThreadPtr thread_2 = std::make_shared<std::thread>(test_func);
+    thread_1->join();
+    thread_2->join();
+}
+
 TEST_F(ConfigTest, CONFIG_TEST) {
     milvus::server::ConfigMgr* config_mgr = milvus::server::YamlConfigMgr::GetInstance();
 
@@ -1256,7 +1290,7 @@ TEST_F(ConfigTest, SERVER_CONFIG_UPDATE_TEST) {
 
     auto lambda = [&conf_file](const std::string& key, const std::string& child_key,
                                const std::string& default_value, std::string& value) {
-        auto * ymgr = milvus::server::YamlConfigMgr::GetInstance();
+        auto* ymgr = milvus::server::YamlConfigMgr::GetInstance();
         auto status = ymgr->LoadConfigFile(conf_file);
 
         if (status.ok())