enhance: make segcore params effective without restarting milvus (#43231)

#43230

Signed-off-by: luzhang <luzhang@zilliz.com>
Co-authored-by: luzhang <luzhang@zilliz.com>

internal/core/src/common/Common.cpp

@@ -19,83 +19,104 @@
 
 namespace milvus {
 
-int64_t FILE_SLICE_SIZE = DEFAULT_INDEX_FILE_SLICE_SIZE;
-float HIGH_PRIORITY_THREAD_CORE_COEFFICIENT =
-    DEFAULT_HIGH_PRIORITY_THREAD_CORE_COEFFICIENT;
-float MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT =
-    DEFAULT_MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT;
-float LOW_PRIORITY_THREAD_CORE_COEFFICIENT =
-    DEFAULT_LOW_PRIORITY_THREAD_CORE_COEFFICIENT;
 int CPU_NUM = DEFAULT_CPU_NUM;
-int64_t EXEC_EVAL_EXPR_BATCH_SIZE = DEFAULT_EXEC_EVAL_EXPR_BATCH_SIZE;
-bool OPTIMIZE_EXPR_ENABLED = DEFAULT_OPTIMIZE_EXPR_ENABLED;
 
-int64_t JSON_KEY_STATS_COMMIT_INTERVAL = DEFAULT_JSON_KEY_STATS_COMMIT_INTERVAL;
+std::atomic<int64_t> FILE_SLICE_SIZE(DEFAULT_INDEX_FILE_SLICE_SIZE);
-bool GROWING_JSON_KEY_STATS_ENABLED = DEFAULT_GROWING_JSON_KEY_STATS_ENABLED;
+std::atomic<float> HIGH_PRIORITY_THREAD_CORE_COEFFICIENT(
-bool CONFIG_PARAM_TYPE_CHECK_ENABLED = DEFAULT_CONFIG_PARAM_TYPE_CHECK_ENABLED;
+    DEFAULT_HIGH_PRIORITY_THREAD_CORE_COEFFICIENT);
+std::atomic<float> MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT(
+    DEFAULT_MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT);
+std::atomic<float> LOW_PRIORITY_THREAD_CORE_COEFFICIENT(
+    DEFAULT_LOW_PRIORITY_THREAD_CORE_COEFFICIENT);
+std::atomic<int64_t> EXEC_EVAL_EXPR_BATCH_SIZE(
+    DEFAULT_EXEC_EVAL_EXPR_BATCH_SIZE);
+std::atomic<bool> OPTIMIZE_EXPR_ENABLED(DEFAULT_OPTIMIZE_EXPR_ENABLED);
+
+std::atomic<int64_t> JSON_KEY_STATS_COMMIT_INTERVAL(
+    DEFAULT_JSON_KEY_STATS_COMMIT_INTERVAL);
+std::atomic<bool> GROWING_JSON_KEY_STATS_ENABLED(
+    DEFAULT_GROWING_JSON_KEY_STATS_ENABLED);
+std::atomic<bool> CONFIG_PARAM_TYPE_CHECK_ENABLED(
+    DEFAULT_CONFIG_PARAM_TYPE_CHECK_ENABLED);
+
+void
+InitCpuNum(const int num) {
+    CPU_NUM = num;
+    LOG_INFO("set cpu num: {}", CPU_NUM);
+}
 
 void
 SetIndexSliceSize(const int64_t size) {
-    FILE_SLICE_SIZE = size << 20;
+    FILE_SLICE_SIZE.store(size << 20);
-    LOG_INFO("set config index slice size (byte): {}", FILE_SLICE_SIZE);
+    LOG_INFO("set config index slice size (byte): {}", FILE_SLICE_SIZE.load());
 }
 
 void
 SetHighPriorityThreadCoreCoefficient(const float coefficient) {
-    HIGH_PRIORITY_THREAD_CORE_COEFFICIENT = coefficient;
+    HIGH_PRIORITY_THREAD_CORE_COEFFICIENT.store(coefficient);
     LOG_INFO("set high priority thread pool core coefficient: {}",
-             HIGH_PRIORITY_THREAD_CORE_COEFFICIENT);
+             HIGH_PRIORITY_THREAD_CORE_COEFFICIENT.load());
 }
 
 void
 SetMiddlePriorityThreadCoreCoefficient(const float coefficient) {
-    MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT = coefficient;
+    MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT.store(coefficient);
     LOG_INFO("set middle priority thread pool core coefficient: {}",
-             MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT);
+             MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT.load());
 }
 
 void
 SetLowPriorityThreadCoreCoefficient(const float coefficient) {
-    LOW_PRIORITY_THREAD_CORE_COEFFICIENT = coefficient;
+    LOW_PRIORITY_THREAD_CORE_COEFFICIENT.store(coefficient);
     LOG_INFO("set low priority thread pool core coefficient: {}",
-             LOW_PRIORITY_THREAD_CORE_COEFFICIENT);
+             LOW_PRIORITY_THREAD_CORE_COEFFICIENT.load());
 }
 
 void
 SetDefaultExecEvalExprBatchSize(int64_t val) {
-    EXEC_EVAL_EXPR_BATCH_SIZE = val;
+    EXEC_EVAL_EXPR_BATCH_SIZE.store(val);
-    LOG_INFO("set default expr eval batch size: {}", EXEC_EVAL_EXPR_BATCH_SIZE);
+    LOG_INFO("set default expr eval batch size: {}",
-}
+             EXEC_EVAL_EXPR_BATCH_SIZE.load());
-
-void
-SetCpuNum(const int num) {
-    CPU_NUM = num;
 }
 
 void
 SetDefaultOptimizeExprEnable(bool val) {
-    OPTIMIZE_EXPR_ENABLED = val;
+    OPTIMIZE_EXPR_ENABLED.store(val);
-    LOG_INFO("set default optimize expr enabled: {}", OPTIMIZE_EXPR_ENABLED);
+    LOG_INFO("set default optimize expr enabled: {}",
+             OPTIMIZE_EXPR_ENABLED.load());
 }
 
 void
 SetDefaultJSONKeyStatsCommitInterval(int64_t val) {
-    JSON_KEY_STATS_COMMIT_INTERVAL = val;
+    JSON_KEY_STATS_COMMIT_INTERVAL.store(val);
     LOG_INFO("set default json key Stats commit interval: {}",
-             JSON_KEY_STATS_COMMIT_INTERVAL);
+             JSON_KEY_STATS_COMMIT_INTERVAL.load());
 }
 
 void
 SetDefaultGrowingJSONKeyStatsEnable(bool val) {
-    GROWING_JSON_KEY_STATS_ENABLED = val;
+    GROWING_JSON_KEY_STATS_ENABLED.store(val);
     LOG_INFO("set default growing json key index enable: {}",
-             GROWING_JSON_KEY_STATS_ENABLED);
+             GROWING_JSON_KEY_STATS_ENABLED.load());
 }
 
 void
 SetDefaultConfigParamTypeCheck(bool val) {
-    CONFIG_PARAM_TYPE_CHECK_ENABLED = val;
+    CONFIG_PARAM_TYPE_CHECK_ENABLED.store(val);
     LOG_INFO("set default config param type check enabled: {}",
-             CONFIG_PARAM_TYPE_CHECK_ENABLED);
+             CONFIG_PARAM_TYPE_CHECK_ENABLED.load());
 }
+
+void
+SetLogLevel(const char* level) {
+    LOG_INFO("set log level: {}", level);
+    if (strcmp(level, "debug") == 0) {
+        FLAGS_v = 5;
+    } else if (strcmp(level, "trace") == 0) {
+        FLAGS_v = 6;
+    } else {
+        FLAGS_v = 4;
+    }
+}
+
 }  // namespace milvus

internal/core/src/common/Common.h

@@ -16,6 +16,7 @@
 
 #pragma once
 
+#include <atomic>
 #include <iostream>
 #include <utility>
 #include <variant>
@@ -23,16 +24,20 @@
 
 namespace milvus {
 
-extern int64_t FILE_SLICE_SIZE;
-extern float HIGH_PRIORITY_THREAD_CORE_COEFFICIENT;
-extern float MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT;
-extern float LOW_PRIORITY_THREAD_CORE_COEFFICIENT;
 extern int CPU_NUM;
-extern int64_t EXEC_EVAL_EXPR_BATCH_SIZE;
+
-extern int64_t JSON_KEY_STATS_COMMIT_INTERVAL;
+extern std::atomic<int64_t> FILE_SLICE_SIZE;
-extern bool OPTIMIZE_EXPR_ENABLED;
+extern std::atomic<float> HIGH_PRIORITY_THREAD_CORE_COEFFICIENT;
-extern bool GROWING_JSON_KEY_STATS_ENABLED;
+extern std::atomic<float> MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT;
-extern bool CONFIG_PARAM_TYPE_CHECK_ENABLED;
+extern std::atomic<float> LOW_PRIORITY_THREAD_CORE_COEFFICIENT;
+extern std::atomic<int64_t> EXEC_EVAL_EXPR_BATCH_SIZE;
+extern std::atomic<int64_t> JSON_KEY_STATS_COMMIT_INTERVAL;
+extern std::atomic<bool> OPTIMIZE_EXPR_ENABLED;
+extern std::atomic<bool> GROWING_JSON_KEY_STATS_ENABLED;
+extern std::atomic<bool> CONFIG_PARAM_TYPE_CHECK_ENABLED;
+
+void
+InitCpuNum(const int core);
 
 void
 SetIndexSliceSize(const int64_t size);
@@ -46,9 +51,6 @@ SetMiddlePriorityThreadCoreCoefficient(const float coefficient);
 void
 SetLowPriorityThreadCoreCoefficient(const float coefficient);
 
-void
-SetCpuNum(const int core);
-
 void
 SetDefaultExecEvalExprBatchSize(int64_t val);
 
@@ -64,6 +66,9 @@ SetDefaultGrowingJSONKeyStatsEnable(bool val);
 void
 SetDefaultConfigParamTypeCheck(bool val);
 
+void
+SetLogLevel(const char* level);
+
 struct BufferView {
     struct Element {
         const char* data_;

internal/core/src/common/Slice.cpp

@@ -90,13 +90,17 @@ Disassemble(BinarySet& binarySet) {
 
     std::vector<std::string> slice_key_list;
     for (auto& kv : binarySet.binary_map_) {
-        if (kv.second->size > FILE_SLICE_SIZE) {
+        if (kv.second->size > FILE_SLICE_SIZE.load()) {
             slice_key_list.push_back(kv.first);
         }
     }
     for (auto& key : slice_key_list) {
         Config slice_i;
-        Slice(key, binarySet.Erase(key), FILE_SLICE_SIZE, binarySet, slice_i);
+        Slice(key,
+              binarySet.Erase(key),
+              FILE_SLICE_SIZE.load(),
+              binarySet,
+              slice_i);
         meta_info[META].emplace_back(slice_i);
     }
     if (!slice_key_list.empty()) {

internal/core/src/common/init_c.cpp

@@ -19,88 +19,62 @@
 #include "common/Common.h"
 #include "common/Tracer.h"
 
-std::once_flag flag1, flag2, flag3, flag4, flag5, flag6, flag7, flag8, flag9,
-    flag10;
 std::once_flag traceFlag;
-
+std::once_flag cpuNumFlag;
-void
-InitIndexSliceSize(const int64_t size) {
-    std::call_once(
-        flag1, [](int64_t size) { milvus::SetIndexSliceSize(size); }, size);
-}
-
-void
-InitHighPriorityThreadCoreCoefficient(const float value) {
-    std::call_once(
-        flag2,
-        [](float value) {
-            milvus::SetHighPriorityThreadCoreCoefficient(value);
-        },
-        value);
-}
-
-void
-InitMiddlePriorityThreadCoreCoefficient(const float value) {
-    std::call_once(
-        flag4,
-        [](float value) {
-            milvus::SetMiddlePriorityThreadCoreCoefficient(value);
-        },
-        value);
-}
-
-void
-InitLowPriorityThreadCoreCoefficient(const float value) {
-    std::call_once(
-        flag5,
-        [](float value) { milvus::SetLowPriorityThreadCoreCoefficient(value); },
-        value);
-}
 
 void
 InitCpuNum(const int value) {
-    std::call_once(
+    std::call_once(cpuNumFlag, [value]() { milvus::InitCpuNum(value); });
-        flag3, [](int value) { milvus::SetCpuNum(value); }, value);
 }
 
 void
-InitDefaultExprEvalBatchSize(int64_t val) {
+SetIndexSliceSize(const int64_t size) {
-    std::call_once(
+    milvus::SetIndexSliceSize(size);
-        flag6,
-        [](int val) { milvus::SetDefaultExecEvalExprBatchSize(val); },
-        val);
 }
 
 void
-InitDefaultOptimizeExprEnable(bool val) {
+SetHighPriorityThreadCoreCoefficient(const float value) {
-    std::call_once(
+    milvus::SetHighPriorityThreadCoreCoefficient(value);
-        flag7,
-        [](bool val) { milvus::SetDefaultOptimizeExprEnable(val); },
-        val);
 }
 
 void
-InitDefaultJSONKeyStatsCommitInterval(int64_t val) {
+SetMiddlePriorityThreadCoreCoefficient(const float value) {
-    std::call_once(
+    milvus::SetMiddlePriorityThreadCoreCoefficient(value);
-        flag8,
-        [](int val) { milvus::SetDefaultJSONKeyStatsCommitInterval(val); },
-        val);
 }
 
 void
-InitDefaultGrowingJSONKeyStatsEnable(bool val) {
+SetLowPriorityThreadCoreCoefficient(const float value) {
-    std::call_once(
+    milvus::SetLowPriorityThreadCoreCoefficient(value);
-        flag9,
-        [](bool val) { milvus::SetDefaultGrowingJSONKeyStatsEnable(val); },
-        val);
 }
 
 void
-InitDefaultConfigParamTypeCheck(bool val) {
+SetDefaultExprEvalBatchSize(int64_t val) {
-    std::call_once(
+    milvus::SetDefaultExecEvalExprBatchSize(val);
-        flag10,
+}
-        [](bool val) { milvus::SetDefaultConfigParamTypeCheck(val); },
+
-        val);
+void
+SetDefaultOptimizeExprEnable(bool val) {
+    milvus::SetDefaultOptimizeExprEnable(val);
+}
+
+void
+SetDefaultJSONKeyStatsCommitInterval(int64_t val) {
+    milvus::SetDefaultJSONKeyStatsCommitInterval(val);
+}
+
+void
+SetDefaultGrowingJSONKeyStatsEnable(bool val) {
+    milvus::SetDefaultGrowingJSONKeyStatsEnable(val);
+}
+
+void
+SetDefaultConfigParamTypeCheck(bool val) {
+    milvus::SetDefaultConfigParamTypeCheck(val);
+}
+
+void
+SetLogLevel(const char* level) {
+    milvus::SetLogLevel(level);
 }
 
 void

internal/core/src/common/init_c.h

@@ -24,42 +24,46 @@ extern "C" {
 #include <stdint.h>
 #include "common/type_c.h"
 
-void
-InitIndexSliceSize(const int64_t);
-
-void
-InitHighPriorityThreadCoreCoefficient(const float);
-
-void
-InitMiddlePriorityThreadCoreCoefficient(const float);
-
-void
-InitLowPriorityThreadCoreCoefficient(const float);
-
-void
-InitDefaultExprEvalBatchSize(int64_t val);
-
 void
 InitCpuNum(const int);
 
+void
+SetIndexSliceSize(const int64_t);
+
+void
+SetHighPriorityThreadCoreCoefficient(const float);
+
+void
+SetMiddlePriorityThreadCoreCoefficient(const float);
+
+void
+SetLowPriorityThreadCoreCoefficient(const float);
+
+void
+SetDefaultExprEvalBatchSize(int64_t val);
+
+void
+SetDefaultOptimizeExprEnable(bool val);
+
+void
+SetDefaultJSONKeyStatsCommitInterval(int64_t val);
+
+void
+SetDefaultGrowingJSONKeyStatsEnable(bool val);
+
+void
+SetDefaultConfigParamTypeCheck(bool val);
+
+// dynamic update segcore params
+void
+SetLogLevel(const char* level);
+
 void
 InitTrace(CTraceConfig* config);
 
 void
 SetTrace(CTraceConfig* config);
 
-void
-InitDefaultOptimizeExprEnable(bool val);
-
-void
-InitDefaultJSONKeyStatsCommitInterval(int64_t val);
-
-void
-InitDefaultGrowingJSONKeyStatsEnable(bool val);
-
-void
-InitDefaultConfigParamTypeCheck(bool val);
-
 #ifdef __cplusplus
 };
 #endif

internal/core/src/exec/QueryContext.h

@@ -133,7 +133,7 @@ class QueryConfig : public MemConfig {
     int64_t
     get_expr_batch_size() const {
         return BaseConfig::Get<int64_t>(kExprEvalBatchSize,
-                                        EXEC_EVAL_EXPR_BATCH_SIZE);
+                                        EXEC_EVAL_EXPR_BATCH_SIZE.load());
     }
 };
 

internal/core/src/exec/expression/Expr.cpp

@@ -68,7 +68,7 @@ CompileExpressions(const std::vector<expr::TypedExprPtr>& sources,
                                              enable_constant_folding));
     }
 
-    if (OPTIMIZE_EXPR_ENABLED) {
+    if (OPTIMIZE_EXPR_ENABLED.load()) {
         OptimizeCompiledExprs(context, exprs);
     }
 

internal/core/src/segcore/memory_planner.cpp

@@ -180,7 +180,7 @@ LoadWithStrategy(const std::vector<std::string>& remote_files,
             futures.reserve(blocks.size());
 
             auto reader_memory_limit = std::max<int64_t>(
-                memory_limit / blocks.size(), FILE_SLICE_SIZE);
+                memory_limit / blocks.size(), FILE_SLICE_SIZE.load());
 
             for (const auto& block : blocks) {
                 futures.emplace_back(pool.Submit([block,

internal/core/src/storage/DiskFileManagerImpl.cpp

@@ -128,7 +128,8 @@ DiskFileManagerImpl::AddFileInternal(
             local_file_offsets.clear();
         }
 
-        auto batch_size = std::min(FILE_SLICE_SIZE, int64_t(fileSize) - offset);
+        auto batch_size =
+            std::min(FILE_SLICE_SIZE.load(), int64_t(fileSize) - offset);
         batch_remote_files.emplace_back(get_remote_path(fileName, slice_num));
         remote_file_sizes.emplace_back(batch_size);
         local_file_offsets.emplace_back(offset);
@@ -258,7 +259,7 @@ DiskFileManagerImpl::CacheIndexToDiskInternal(
         batch_remote_files.reserve(slices.second.size());
 
         uint64_t max_parallel_degree =
-            uint64_t(DEFAULT_FIELD_MAX_MEMORY_LIMIT / FILE_SLICE_SIZE);
+            uint64_t(DEFAULT_FIELD_MAX_MEMORY_LIMIT / FILE_SLICE_SIZE.load());
 
         {
             auto file_writer = storage::FileWriter(local_index_file_name);

internal/core/src/storage/ThreadPools.cpp

@@ -41,13 +41,13 @@ ThreadPools::GetThreadPool(milvus::ThreadPoolPriority priority) {
         float coefficient = 1.0;
         switch (priority) {
             case milvus::ThreadPoolPriority::HIGH:
-                coefficient = HIGH_PRIORITY_THREAD_CORE_COEFFICIENT;
+                coefficient = HIGH_PRIORITY_THREAD_CORE_COEFFICIENT.load();
                 break;
             case milvus::ThreadPoolPriority::MIDDLE:
-                coefficient = MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT;
+                coefficient = MIDDLE_PRIORITY_THREAD_CORE_COEFFICIENT.load();
                 break;
             default:
-                coefficient = LOW_PRIORITY_THREAD_CORE_COEFFICIENT;
+                coefficient = LOW_PRIORITY_THREAD_CORE_COEFFICIENT.load();
                 break;
         }
         std::string name = name_map()[priority];

internal/core/unittest/test_exec.cpp

@@ -679,7 +679,7 @@ TEST_P(TaskTest, Test_reorder) {
         auto query_context = std::make_shared<milvus::exec::QueryContext>(
             DEAFULT_QUERY_ID, segment_.get(), 100000, MAX_TIMESTAMP);
         ExecContext context(query_context.get());
-        OPTIMIZE_EXPR_ENABLED = false;
+        OPTIMIZE_EXPR_ENABLED.store(false);
         auto exprs =
             milvus::exec::CompileExpressions({expr3}, &context, {}, false);
         EXPECT_EQ(exprs.size(), 1);
@@ -690,7 +690,7 @@ TEST_P(TaskTest, Test_reorder) {
         std::cout << phy_expr->ToString() << std::endl;
         auto reorder = phy_expr->GetReorder();
         EXPECT_EQ(reorder.size(), 0);
-        OPTIMIZE_EXPR_ENABLED = true;
+        OPTIMIZE_EXPR_ENABLED.store(true, std::memory_order_release);
     }
 }
 

internal/core/unittest/test_expr.cpp

@@ -4234,7 +4234,7 @@ TEST_P(ExprTest, TestMutiInConvert) {
     auto plan =
         std::make_shared<plan::FilterBitsNode>(DEFAULT_PLANNODE_ID, expr);
     auto final1 = ExecuteQueryExpr(plan, seg.get(), N, MAX_TIMESTAMP);
-    OPTIMIZE_EXPR_ENABLED = false;
+    OPTIMIZE_EXPR_ENABLED.store(false);
     auto final2 = ExecuteQueryExpr(plan, seg.get(), N, MAX_TIMESTAMP);
     EXPECT_EQ(final1.size(), final2.size());
     for (auto i = 0; i < final1.size(); i++) {
@@ -5071,7 +5071,7 @@ TEST_P(ExprTest, TestGrowingSegmentGetBatchSize) {
         8192, 10240, 20480, 30720, 40960, 102400, 204800, 307200};
 
     for (const auto& batch_size : test_batch_size) {
-        EXEC_EVAL_EXPR_BATCH_SIZE = batch_size;
+        EXEC_EVAL_EXPR_BATCH_SIZE.store(batch_size);
         auto plan = plan::PlanFragment(plan_node);
         auto query_context = std::make_shared<milvus::exec::QueryContext>(
             "query id", seg.get(), N, MAX_TIMESTAMP);

internal/datanode/index/init_segcore.go

@@ -50,15 +50,15 @@ func InitSegcore() {
 
 	// override segcore index slice size
 	cIndexSliceSize := C.int64_t(paramtable.Get().CommonCfg.IndexSliceSize.GetAsInt64())
-	C.InitIndexSliceSize(cIndexSliceSize)
+	C.SetIndexSliceSize(cIndexSliceSize)
 
 	// set up thread pool for different priorities
 	cHighPriorityThreadCoreCoefficient := C.float(paramtable.Get().CommonCfg.HighPriorityThreadCoreCoefficient.GetAsFloat())
-	C.InitHighPriorityThreadCoreCoefficient(cHighPriorityThreadCoreCoefficient)
+	C.SetHighPriorityThreadCoreCoefficient(cHighPriorityThreadCoreCoefficient)
 	cMiddlePriorityThreadCoreCoefficient := C.float(paramtable.Get().CommonCfg.MiddlePriorityThreadCoreCoefficient.GetAsFloat())
-	C.InitMiddlePriorityThreadCoreCoefficient(cMiddlePriorityThreadCoreCoefficient)
+	C.SetMiddlePriorityThreadCoreCoefficient(cMiddlePriorityThreadCoreCoefficient)
 	cLowPriorityThreadCoreCoefficient := C.float(paramtable.Get().CommonCfg.LowPriorityThreadCoreCoefficient.GetAsFloat())
-	C.InitLowPriorityThreadCoreCoefficient(cLowPriorityThreadCoreCoefficient)
+	C.SetLowPriorityThreadCoreCoefficient(cLowPriorityThreadCoreCoefficient)
 
 	cCPUNum := C.int(hardware.GetCPUNum())
 	C.InitCpuNum(cCPUNum)

internal/querynodev2/server.go

@@ -250,15 +250,15 @@ func (node *QueryNode) InitSegcore() error {
 
 	// override segcore index slice size
 	cIndexSliceSize := C.int64_t(paramtable.Get().CommonCfg.IndexSliceSize.GetAsInt64())
-	C.InitIndexSliceSize(cIndexSliceSize)
+	C.SetIndexSliceSize(cIndexSliceSize)
 
 	// set up thread pool for different priorities
 	cHighPriorityThreadCoreCoefficient := C.float(paramtable.Get().CommonCfg.HighPriorityThreadCoreCoefficient.GetAsFloat())
-	C.InitHighPriorityThreadCoreCoefficient(cHighPriorityThreadCoreCoefficient)
+	C.SetHighPriorityThreadCoreCoefficient(cHighPriorityThreadCoreCoefficient)
 	cMiddlePriorityThreadCoreCoefficient := C.float(paramtable.Get().CommonCfg.MiddlePriorityThreadCoreCoefficient.GetAsFloat())
-	C.InitMiddlePriorityThreadCoreCoefficient(cMiddlePriorityThreadCoreCoefficient)
+	C.SetMiddlePriorityThreadCoreCoefficient(cMiddlePriorityThreadCoreCoefficient)
 	cLowPriorityThreadCoreCoefficient := C.float(paramtable.Get().CommonCfg.LowPriorityThreadCoreCoefficient.GetAsFloat())
-	C.InitLowPriorityThreadCoreCoefficient(cLowPriorityThreadCoreCoefficient)
+	C.SetLowPriorityThreadCoreCoefficient(cLowPriorityThreadCoreCoefficient)
 
 	node.RegisterSegcoreConfigWatcher()
 
@@ -274,22 +274,22 @@ func (node *QueryNode) InitSegcore() error {
 	C.SegcoreSetKnowhereBuildThreadPoolNum(cKnowhereBuildPoolSize)
 
 	cExprBatchSize := C.int64_t(paramtable.Get().QueryNodeCfg.ExprEvalBatchSize.GetAsInt64())
-	C.InitDefaultExprEvalBatchSize(cExprBatchSize)
+	C.SetDefaultExprEvalBatchSize(cExprBatchSize)
 
 	cOptimizeExprEnabled := C.bool(paramtable.Get().CommonCfg.EnabledOptimizeExpr.GetAsBool())
-	C.InitDefaultOptimizeExprEnable(cOptimizeExprEnabled)
+	C.SetDefaultOptimizeExprEnable(cOptimizeExprEnabled)
 
 	cJSONKeyStatsCommitInterval := C.int64_t(paramtable.Get().QueryNodeCfg.JSONKeyStatsCommitInterval.GetAsInt64())
-	C.InitDefaultJSONKeyStatsCommitInterval(cJSONKeyStatsCommitInterval)
+	C.SetDefaultJSONKeyStatsCommitInterval(cJSONKeyStatsCommitInterval)
 
 	cGrowingJSONKeyStatsEnabled := C.bool(paramtable.Get().CommonCfg.EnabledGrowingSegmentJSONKeyStats.GetAsBool())
-	C.InitDefaultGrowingJSONKeyStatsEnable(cGrowingJSONKeyStatsEnabled)
+	C.SetDefaultGrowingJSONKeyStatsEnable(cGrowingJSONKeyStatsEnabled)
 	cGpuMemoryPoolInitSize := C.uint32_t(paramtable.Get().GpuConfig.InitSize.GetAsUint32())
 	cGpuMemoryPoolMaxSize := C.uint32_t(paramtable.Get().GpuConfig.MaxSize.GetAsUint32())
 	C.SegcoreSetKnowhereGpuMemoryPoolSize(cGpuMemoryPoolInitSize, cGpuMemoryPoolMaxSize)
 
 	cEnableConfigParamTypeCheck := C.bool(paramtable.Get().CommonCfg.EnableConfigParamTypeCheck.GetAsBool())
-	C.InitDefaultConfigParamTypeCheck(cEnableConfigParamTypeCheck)
+	C.SetDefaultConfigParamTypeCheck(cEnableConfigParamTypeCheck)
 
 	localDataRootPath := filepath.Join(paramtable.Get().LocalStorageCfg.Path.GetValue(), typeutil.QueryNodeRole)
 	initcore.InitLocalChunkManager(localDataRootPath)

pkg/util/paramtable/autoindex_param_test.go

@@ -138,10 +138,9 @@ func Test_autoIndexConfig_panicIfNotValid(t *testing.T) {
 				Formatter: GetBuildParamFormatter(FloatVectorDefaultMetricType, "autoIndex.params.build"),
 			},
 		}
-		p.IndexParams.Init(mgr)
 
 		assert.Panics(t, func() {
-			p.IndexParams.GetAsJSONMap()
+			p.IndexParams.Init(mgr)
 		})
 	})
 }

pkg/util/paramtable/base_table.go

@@ -143,7 +143,14 @@ func (bt *BaseTable) init() {
 		ret = strings.ReplaceAll(ret, ".", "")
 		return ret
 	}
-	bt.mgr, _ = config.Init()
+
+	var err error
+	bt.mgr, err = config.Init()
+	if err != nil {
+		log.Error("failed to initialize config manager", zap.Error(err))
+		panic(err)
+	}
+
 	if !bt.config.skipEnv {
 		err := bt.mgr.AddSource(config.NewEnvSource(formatter))
 		if err != nil {

pkg/util/paramtable/component_param.go

@@ -17,6 +17,7 @@
 package paramtable
 
 import (
+	"context"
 	"fmt"
 	"os"
 	"path"
@@ -530,6 +531,14 @@ This configuration is only used by querynode and indexnode, it selects CPU instr
 		Export:       true,
 	}
 	p.IndexSliceSize.Init(base.mgr)
+	p.IndexSliceSize.RegisterCallback(func(ctx context.Context, key, oldValue, newValue string) error {
+		size, err := strconv.Atoi(newValue)
+		if err != nil {
+			return err
+		}
+		UpdateIndexSliceSize(size)
+		return nil
+	})
 
 	p.EnableMaterializedView = ParamItem{
 		Key:          "common.materializedView.enabled",
@@ -631,6 +640,14 @@ This configuration is only used by querynode and indexnode, it selects CPU instr
 		Export: true,
 	}
 	p.HighPriorityThreadCoreCoefficient.Init(base.mgr)
+	p.HighPriorityThreadCoreCoefficient.RegisterCallback(func(ctx context.Context, key, oldValue, newValue string) error {
+		coefficient, err := strconv.ParseFloat(newValue, 64)
+		if err != nil {
+			return err
+		}
+		UpdateHighPriorityThreadCoreCoefficient(coefficient)
+		return nil
+	})
 
 	p.MiddlePriorityThreadCoreCoefficient = ParamItem{
 		Key:          "common.threadCoreCoefficient.middlePriority",
@@ -641,6 +658,14 @@ This configuration is only used by querynode and indexnode, it selects CPU instr
 		Export: true,
 	}
 	p.MiddlePriorityThreadCoreCoefficient.Init(base.mgr)
+	p.MiddlePriorityThreadCoreCoefficient.RegisterCallback(func(ctx context.Context, key, oldValue, newValue string) error {
+		coefficient, err := strconv.ParseFloat(newValue, 64)
+		if err != nil {
+			return err
+		}
+		UpdateMiddlePriorityThreadCoreCoefficient(coefficient)
+		return nil
+	})
 
 	p.LowPriorityThreadCoreCoefficient = ParamItem{
 		Key:          "common.threadCoreCoefficient.lowPriority",
@@ -651,6 +676,14 @@ This configuration is only used by querynode and indexnode, it selects CPU instr
 		Export: true,
 	}
 	p.LowPriorityThreadCoreCoefficient.Init(base.mgr)
+	p.LowPriorityThreadCoreCoefficient.RegisterCallback(func(ctx context.Context, key, oldValue, newValue string) error {
+		coefficient, err := strconv.ParseFloat(newValue, 64)
+		if err != nil {
+			return err
+		}
+		UpdateLowPriorityThreadCoreCoefficient(coefficient)
+		return nil
+	})
 
 	p.DiskWriteMode = ParamItem{
 		Key:          "common.diskWriteMode",
@@ -1064,6 +1097,15 @@ This helps Milvus-CDC synchronize incremental data`,
 		Export:       true,
 	}
 	p.EnabledOptimizeExpr.Init(base.mgr)
+	p.EnabledOptimizeExpr.RegisterCallback(func(ctx context.Context, key, oldValue, newValue string) error {
+		enable, err := strconv.ParseBool(newValue)
+		if err != nil {
+			return err
+		}
+		UpdateDefaultOptimizeExprEnable(enable)
+		return nil
+	})
+
 	p.EnabledJSONKeyStats = ParamItem{
 		Key:          "common.enabledJSONKeyStats",
 		Version:      "2.5.5",
@@ -1081,6 +1123,14 @@ This helps Milvus-CDC synchronize incremental data`,
 		Export:       true,
 	}
 	p.EnabledGrowingSegmentJSONKeyStats.Init(base.mgr)
+	p.EnabledGrowingSegmentJSONKeyStats.RegisterCallback(func(ctx context.Context, key, oldValue, newValue string) error {
+		enable, err := strconv.ParseBool(newValue)
+		if err != nil {
+			return err
+		}
+		UpdateDefaultGrowingJSONKeyStatsEnable(enable)
+		return nil
+	})
 
 	p.EnableConfigParamTypeCheck = ParamItem{
 		Key:          "common.enableConfigParamTypeCheck",
@@ -1090,6 +1140,14 @@ This helps Milvus-CDC synchronize incremental data`,
 		Export:       true,
 	}
 	p.EnableConfigParamTypeCheck.Init(base.mgr)
+	p.EnableConfigParamTypeCheck.RegisterCallback(func(ctx context.Context, key, oldValue, newValue string) error {
+		enable, err := strconv.ParseBool(newValue)
+		if err != nil {
+			return err
+		}
+		UpdateDefaultConfigParamTypeCheck(enable)
+		return nil
+	})
 }
 
 type gpuConfig struct {
@@ -1330,6 +1388,9 @@ It is recommended to use debug level under test and development environments, an
 		Export: true,
 	}
 	l.Level.Init(base.mgr)
+	l.Level.RegisterCallback(func(ctx context.Context, key, oldValue, newValue string) error {
+		return UpdateLogLevel(newValue)
+	})
 
 	l.RootPath = ParamItem{
 		Key:     "log.file.rootPath",
@@ -3223,6 +3284,15 @@ If set to 0, time based eviction is disabled.`,
 	}
 	p.CacheCellUnaccessedSurvivalTime.Init(base.mgr)
 
+	p.EnableDisk = ParamItem{
+		Key:          "queryNode.enableDisk",
+		Version:      "2.2.0",
+		DefaultValue: "false",
+		Doc:          "enable querynode load disk index, and search on disk index",
+		Export:       true,
+	}
+	p.EnableDisk.Init(base.mgr)
+
 	p.KnowhereThreadPoolSize = ParamItem{
 		Key:          "queryNode.segcore.knowhereThreadPoolNumRatio",
 		Version:      "2.0.0",
@@ -3671,15 +3741,6 @@ Max read concurrency must greater than or equal to 1, and less than or equal to
 	}
 	p.CPURatio.Init(base.mgr)
 
-	p.EnableDisk = ParamItem{
-		Key:          "queryNode.enableDisk",
-		Version:      "2.2.0",
-		DefaultValue: "false",
-		Doc:          "enable querynode load disk index, and search on disk index",
-		Export:       true,
-	}
-	p.EnableDisk.Init(base.mgr)
-
 	p.IndexOffsetCacheEnabled = ParamItem{
 		Key:          "queryNode.indexOffsetCacheEnabled",
 		Version:      "2.5.0",
@@ -3882,6 +3943,14 @@ user-task-polling:
 		Doc:          "expr eval batch size for getnext interface",
 	}
 	p.ExprEvalBatchSize.Init(base.mgr)
+	p.ExprEvalBatchSize.RegisterCallback(func(ctx context.Context, key, oldValue, newValue string) error {
+		size, err := strconv.Atoi(newValue)
+		if err != nil {
+			return err
+		}
+		UpdateDefaultExprEvalBatchSize(size)
+		return nil
+	})
 
 	p.JSONKeyStatsCommitInterval = ParamItem{
 		Key:          "queryNode.segcore.jsonKeyStatsCommitInterval",
@@ -3891,6 +3960,14 @@ user-task-polling:
 		Export:       true,
 	}
 	p.JSONKeyStatsCommitInterval.Init(base.mgr)
+	p.JSONKeyStatsCommitInterval.RegisterCallback(func(ctx context.Context, key, oldValue, newValue string) error {
+		interval, err := strconv.Atoi(newValue)
+		if err != nil {
+			return err
+		}
+		UpdateDefaultJSONKeyStatsCommitInterval(interval)
+		return nil
+	})
 
 	p.CleanExcludeSegInterval = ParamItem{
 		Key:          "queryCoord.cleanExcludeSegmentInterval",

pkg/util/paramtable/param_item.go

@@ -17,6 +17,7 @@
 package paramtable
 
 import (
+	"context"
 	"fmt"
 	"strconv"
 	"strings"
@@ -24,11 +25,15 @@ import (
 
 	"github.com/samber/lo"
 	"go.uber.org/atomic"
+	"go.uber.org/zap"
 
 	"github.com/milvus-io/milvus/pkg/v2/config"
+	"github.com/milvus-io/milvus/pkg/v2/log"
 	"github.com/milvus-io/milvus/pkg/v2/util/funcutil"
 )
 
+type ParamChangeCallback func(ctx context.Context, key, oldValue, newValue string) error
+
 type ParamItem struct {
 	Key          string // which should be named as "A.B.C"
 	Version      string
@@ -45,6 +50,9 @@ type ParamItem struct {
 
 	// for unittest.
 	tempValue atomic.Pointer[string]
+
+	callback  ParamChangeCallback
+	lastValue atomic.Pointer[string]
 }
 
 func (pi *ParamItem) Init(manager *config.Manager) {
@@ -52,6 +60,58 @@ func (pi *ParamItem) Init(manager *config.Manager) {
 	if pi.Forbidden {
 		pi.manager.ForbidUpdate(pi.Key)
 	}
+
+	currentValue := pi.GetValue()
+	pi.lastValue.Store(&currentValue)
+
+	if manager != nil && manager.Dispatcher != nil {
+		handler := config.NewHandler(pi.Key, func(event *config.Event) {
+			if event.Key == strings.ToLower(pi.Key) && event.EventType == config.UpdateType {
+				pi.handleConfigChange(event)
+			}
+		})
+		manager.Dispatcher.Register(pi.Key, handler)
+	}
+}
+
+func (pi *ParamItem) RegisterCallback(callback ParamChangeCallback) {
+	pi.callback = callback
+}
+
+func (pi *ParamItem) UnregisterCallback() {
+	pi.callback = nil
+}
+
+func (pi *ParamItem) handleConfigChange(event *config.Event) {
+	if pi.callback == nil {
+		return
+	}
+
+	oldValue := ""
+	if lastVal := pi.lastValue.Load(); lastVal != nil {
+		oldValue = *lastVal
+	}
+
+	newValue := event.Value
+
+	if oldValue == newValue {
+		return
+	}
+
+	if err := pi.callback(context.Background(), pi.Key, oldValue, newValue); err != nil {
+		log.Error("param change callback failed",
+			zap.String("key", pi.Key),
+			zap.String("oldValue", oldValue),
+			zap.String("newValue", newValue),
+			zap.Error(err))
+	} else {
+		log.Info("param value changed",
+			zap.String("key", pi.Key),
+			zap.String("oldValue", oldValue),
+			zap.String("newValue", newValue))
+	}
+
+	pi.lastValue.Store(&newValue)
 }
 
 // Get original value with error

pkg/util/paramtable/param_item_callback_test.go

@@ -0,0 +1,458 @@
+// Licensed to the LF AI & Data foundation under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package paramtable
+
+import (
+	"context"
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/milvus-io/milvus/pkg/v2/config"
+)
+
+func TestParamItem_RegisterCallback(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+	param.Init(manager)
+
+	callback := func(ctx context.Context, key, oldValue, newValue string) error {
+		return nil
+	}
+
+	param.RegisterCallback(callback)
+	assert.NotNil(t, param.callback)
+
+	param.UnregisterCallback()
+	assert.Nil(t, param.callback)
+}
+
+func TestParamItem_CallbackTriggered(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+	param.Init(manager)
+
+	var callbackCalled bool
+	var capturedOldValue, capturedNewValue string
+	var capturedKey string
+
+	callback := func(ctx context.Context, key, oldValue, newValue string) error {
+		callbackCalled = true
+		capturedKey = key
+		capturedOldValue = oldValue
+		capturedNewValue = newValue
+		return nil
+	}
+
+	param.RegisterCallback(callback)
+
+	assert.Equal(t, "default", param.GetValue())
+
+	event := &config.Event{
+		EventType: config.UpdateType,
+		Key:       "test.param",
+		Value:     "new-value",
+	}
+
+	param.handleConfigChange(event)
+
+	assert.True(t, callbackCalled)
+	assert.Equal(t, "test.param", capturedKey)
+	assert.Equal(t, "default", capturedOldValue)
+	assert.Equal(t, "new-value", capturedNewValue)
+}
+
+func TestParamItem_CallbackErrorHandling(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+	param.Init(manager)
+
+	var callbackCalled bool
+
+	errorCallback := func(ctx context.Context, key, oldValue, newValue string) error {
+		callbackCalled = true
+		return fmt.Errorf("callback error")
+	}
+
+	param.RegisterCallback(errorCallback)
+
+	event := &config.Event{
+		EventType: config.UpdateType,
+		Key:       "test.param",
+		Value:     "new-value",
+	}
+
+	param.handleConfigChange(event)
+
+	assert.True(t, callbackCalled)
+}
+
+func TestParamItem_NoValueChange(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+	param.Init(manager)
+
+	var callbackCalled bool
+
+	callback := func(ctx context.Context, key, oldValue, newValue string) error {
+		callbackCalled = true
+		return nil
+	}
+
+	param.RegisterCallback(callback)
+
+	event := &config.Event{
+		EventType: config.UpdateType,
+		Key:       "test.param",
+		Value:     "default",
+	}
+
+	param.handleConfigChange(event)
+
+	assert.False(t, callbackCalled)
+}
+
+func TestParamItem_CallbackWithContext(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+	param.Init(manager)
+
+	var callbackCalled bool
+
+	callback := func(ctx context.Context, key, oldValue, newValue string) error {
+		callbackCalled = true
+		assert.NotNil(t, ctx)
+		return nil
+	}
+
+	param.RegisterCallback(callback)
+
+	event := &config.Event{
+		EventType: config.UpdateType,
+		Key:       "test.param",
+		Value:     "new-value",
+	}
+
+	param.handleConfigChange(event)
+
+	assert.True(t, callbackCalled)
+}
+
+func TestParamItem_CallbackCleanup(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+	param.Init(manager)
+
+	var callbackCalled bool
+
+	callback := func(ctx context.Context, key, oldValue, newValue string) error {
+		callbackCalled = true
+		return nil
+	}
+
+	param.RegisterCallback(callback)
+
+	param.UnregisterCallback()
+
+	event := &config.Event{
+		EventType: config.UpdateType,
+		Key:       "test.param",
+		Value:     "new-value",
+	}
+
+	param.handleConfigChange(event)
+
+	assert.False(t, callbackCalled)
+}
+
+func TestParamItem_ManagerNil(t *testing.T) {
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+
+	callback := func(ctx context.Context, key, oldValue, newValue string) error {
+		return nil
+	}
+
+	param.RegisterCallback(callback)
+	assert.NotNil(t, param.callback)
+
+	param.UnregisterCallback()
+	assert.Nil(t, param.callback)
+}
+
+func TestParamItem_DispatcherNil(t *testing.T) {
+	manager := config.NewManager()
+	manager.Dispatcher = nil
+
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+
+	param.Init(manager)
+
+	callback := func(ctx context.Context, key, oldValue, newValue string) error {
+		return nil
+	}
+
+	param.RegisterCallback(callback)
+	assert.NotNil(t, param.callback)
+}
+
+func TestParamItem_StressTest(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+	param.Init(manager)
+
+	var callbackCount int
+
+	callback := func(ctx context.Context, key, oldValue, newValue string) error {
+		callbackCount++
+		return nil
+	}
+
+	param.RegisterCallback(callback)
+
+	for i := 0; i < 10; i++ {
+		event := &config.Event{
+			EventType: config.UpdateType,
+			Key:       "test.param",
+			Value:     fmt.Sprintf("value-%d", i),
+		}
+		param.handleConfigChange(event)
+	}
+
+	assert.Equal(t, 10, callbackCount)
+}
+
+func TestParamItem_FormatterWithCallback(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "100",
+		Formatter: func(v string) string {
+			if v == "100" {
+				return "formatted-100"
+			}
+			return v
+		},
+	}
+	param.Init(manager)
+
+	var callbackCalled bool
+	var callbackNewValue string
+
+	callback := func(ctx context.Context, key, oldValue, newValue string) error {
+		callbackCalled = true
+		callbackNewValue = newValue
+		return nil
+	}
+
+	param.RegisterCallback(callback)
+
+	event := &config.Event{
+		EventType: config.UpdateType,
+		Key:       "test.param",
+		Value:     "200",
+	}
+
+	param.handleConfigChange(event)
+
+	assert.True(t, callbackCalled)
+	assert.Equal(t, "200", callbackNewValue)
+}
+
+func TestParamItem_InitWithManager(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+
+	assert.Nil(t, param.manager)
+
+	param.Init(manager)
+
+	assert.NotNil(t, param.manager)
+	assert.Equal(t, manager, param.manager)
+
+	assert.NotNil(t, manager.Dispatcher)
+}
+
+func TestParamItem_LastValueTracking_Change(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+	param.Init(manager)
+
+	initialValue := param.GetValue()
+	assert.Equal(t, "default", initialValue)
+
+	lastVal := param.lastValue.Load()
+	assert.NotNil(t, lastVal)
+	assert.Equal(t, "default", *lastVal)
+
+	var callbackNewValue string
+
+	callback := func(ctx context.Context, key, oldValue, newValue string) error {
+		callbackNewValue = newValue
+		return nil
+	}
+
+	param.RegisterCallback(callback)
+
+	event := &config.Event{
+		EventType: config.UpdateType,
+		Key:       "test.param",
+		Value:     "new-value",
+	}
+
+	param.handleConfigChange(event)
+
+	lastVal = param.lastValue.Load()
+	assert.NotNil(t, lastVal)
+	assert.Equal(t, "new-value", *lastVal)
+	assert.Equal(t, "new-value", callbackNewValue)
+}
+
+func TestParamItem_LastValueTracking_NoChange(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+	param.Init(manager)
+
+	initialValue := param.GetValue()
+	assert.Equal(t, "default", initialValue)
+
+	lastVal := param.lastValue.Load()
+	assert.NotNil(t, lastVal)
+	assert.Equal(t, "default", *lastVal)
+
+	event := &config.Event{
+		EventType: config.UpdateType,
+		Key:       "test.param",
+		Value:     "new-value",
+	}
+
+	param.handleConfigChange(event)
+
+	lastVal = param.lastValue.Load()
+	assert.NotNil(t, lastVal)
+	assert.Equal(t, "default", *lastVal)
+}
+
+func TestParamItem_EventTypeFiltering(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+	param.Init(manager)
+
+	var callbackCalled bool
+
+	callback := func(ctx context.Context, key, oldValue, newValue string) error {
+		callbackCalled = true
+		return nil
+	}
+
+	param.RegisterCallback(callback)
+
+	createEvent := &config.Event{
+		EventType: config.CreateType,
+		Key:       "test.param",
+		Value:     "new-value",
+	}
+
+	param.handleConfigChange(createEvent)
+	assert.True(t, callbackCalled)
+
+	callbackCalled = false
+
+	updateEvent := &config.Event{
+		EventType: config.UpdateType,
+		Key:       "test.param",
+		Value:     "another-value",
+	}
+
+	param.handleConfigChange(updateEvent)
+	assert.True(t, callbackCalled)
+}
+
+func TestParamItem_NilCallback(t *testing.T) {
+	manager := config.NewManager()
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+	param.Init(manager)
+
+	event := &config.Event{
+		EventType: config.UpdateType,
+		Key:       "test.param",
+		Value:     "new-value",
+	}
+
+	assert.NotPanics(t, func() {
+		param.handleConfigChange(event)
+	})
+}
+
+func TestParamItem_CallbackNilManager(t *testing.T) {
+	param := &ParamItem{
+		Key:          "test.param",
+		DefaultValue: "default",
+	}
+
+	event := &config.Event{
+		EventType: config.UpdateType,
+		Key:       "test.param",
+		Value:     "new-value",
+	}
+
+	assert.NotPanics(t, func() {
+		param.handleConfigChange(event)
+	})
+}

pkg/util/paramtable/util.go

@@ -0,0 +1,71 @@
+// Licensed to the LF AI & Data foundation under one
+// or more contributor license agreements. See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership. The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package paramtable
+
+/*
+#cgo pkg-config: milvus_core
+
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include "common/init_c.h"
+*/
+import "C"
+import "unsafe"
+
+func UpdateLogLevel(level string) error {
+	cvalue := C.CString(level)
+	C.SetLogLevel(cvalue)
+	C.free(unsafe.Pointer(cvalue))
+	return nil
+}
+
+func UpdateIndexSliceSize(size int) {
+	C.SetIndexSliceSize(C.int64_t(size))
+}
+
+func UpdateHighPriorityThreadCoreCoefficient(coefficient float64) {
+	C.SetHighPriorityThreadCoreCoefficient(C.float(coefficient))
+}
+
+func UpdateMiddlePriorityThreadCoreCoefficient(coefficient float64) {
+	C.SetMiddlePriorityThreadCoreCoefficient(C.float(coefficient))
+}
+
+func UpdateLowPriorityThreadCoreCoefficient(coefficient float64) {
+	C.SetLowPriorityThreadCoreCoefficient(C.float(coefficient))
+}
+
+func UpdateDefaultExprEvalBatchSize(size int) {
+	C.SetDefaultExprEvalBatchSize(C.int64_t(size))
+}
+
+func UpdateDefaultOptimizeExprEnable(enable bool) {
+	C.SetDefaultOptimizeExprEnable(C.bool(enable))
+}
+
+func UpdateDefaultJSONKeyStatsCommitInterval(interval int) {
+	C.SetDefaultJSONKeyStatsCommitInterval(C.int64_t(interval))
+}
+
+func UpdateDefaultGrowingJSONKeyStatsEnable(enable bool) {
+	C.SetDefaultGrowingJSONKeyStatsEnable(C.bool(enable))
+}
+
+func UpdateDefaultConfigParamTypeCheck(enable bool) {
+	C.SetDefaultConfigParamTypeCheck(C.bool(enable))
+}