diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9802fbb..bfcc898 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -18,7 +18,7 @@ option(FFRT_BENCHMARKS "Enables ffrt Benchmarks" OFF)
 option(FFRT_TEST_ENABLE "Enables ffrt test" OFF)
 option(FFRT_CLANG_COMPILE "use clang/clang++ for compiling" ON)
 option(FFRT_SANITIZE "enable address or thread sanitizer" OFF)
-option(FFRT_IO_TASK_SCHEDULER "enalbe io task scheduler" ON)
+option(FFRT_IO_TASK_SCHEDULER "enalbe io task scheduler" OFF)
 
 # set compiler clang or gcc, must before project(ffrt)
 if(FFRT_CLANG_COMPILE STREQUAL ON)
diff --git a/interfaces/inner_api/c/executor_task.h b/interfaces/inner_api/c/executor_task.h
index c41af61..8eb927a 100644
--- a/interfaces/inner_api/c/executor_task.h
+++ b/interfaces/inner_api/c/executor_task.h
@@ -33,13 +33,15 @@ typedef void (*ffrt_executor_task_func)(ffrt_executor_task_t* data, ffrt_qos_t q
 
 FFRT_C_API void ffrt_executor_task_register_func(ffrt_executor_task_func func, ffrt_executor_task_type_t type);
 FFRT_C_API void ffrt_executor_task_submit(ffrt_executor_task_t *task, const ffrt_task_attr_t *attr);
-FFRT_C_API int ffrt_executor_task_cancel(ffrt_executor_task_t *taask, const ffrt_qos_t qos);
+FFRT_C_API int ffrt_executor_task_cancel(ffrt_executor_task_t *task, const ffrt_qos_t qos);
 
 #ifdef FFRT_IO_TASK_SCHEDULER
 // poller
-FFRT_C_API int ffrt_poller_register(int fd, uint32_t events, void* data, void(*cb)(void*, uint32_t));
+typedef void (*ffrt_poller_cb)(void*, uint32_t);
+typedef int (*ffrt_timer_func)();
+FFRT_C_API int ffrt_poller_register(int fd, uint32_t events, void* data, ffrt_poller_cb cb);
 FFRT_C_API int ffrt_poller_deregister(int fd);
-FFRT_C_API int ffrt_poller_register_timerfunc(int(*timerFunc)());
+FFRT_C_API int ffrt_poller_register_timerfunc(ffrt_timer_func timerFunc);
 FFRT_C_API void ffrt_poller_wakeup();
 
 FFRT_C_API void ffrt_submit_coroutine(void* co, ffrt_coroutine_ptr_t exec,
diff --git a/interfaces/inner_api/c/type_def.h b/interfaces/inner_api/c/type_def.h
index 5cf40c7..0734d82 100644
--- a/interfaces/inner_api/c/type_def.h
+++ b/interfaces/inner_api/c/type_def.h
@@ -82,6 +82,26 @@ typedef void* ffrt_sys_event_handle_t;
 
 typedef void* ffrt_config_t;
 
+#ifdef FFRT_IO_TASK_SCHEDULER
+typedef enum {
+    ffrt_coroutine_stackless,
+    ffrt_coroutine_with_stack,
+} ffrt_coroutine_t;
+
+typedef enum {
+    ffrt_coroutine_pending = 0,
+    ffrt_coroutine_ready = 0,
+} ffrt_coroutine_ret_t;
+
+typedef ffrt_coroutine_ret_t(*ffrt_coroutine_ptr_t)(void*);
+
+typedef struct {
+    int fd;
+    void* data;
+    void(*cb)(void*, uint32_t);
+} ffrt_poller_t;
+#endif
+
 #ifdef __cplusplus
 namespace ffrt {
 enum qos_inner_default {
diff --git a/interfaces/kits/c/type_def.h b/interfaces/kits/c/type_def.h
index 1cedf23..ece8ab0 100644
--- a/interfaces/kits/c/type_def.h
+++ b/interfaces/kits/c/type_def.h
@@ -103,7 +103,10 @@ typedef enum {
     /** General task. */
     ffrt_function_kind_general,
     /** Queue task. */
-    ffrt_function_kind_queue
+    ffrt_function_kind_queue,
+#ifdef FFRT_IO_TASK_SCHEDULER
+    ffrt_function_kind_io,
+#endif
 } ffrt_function_kind_t;
 
 /**
diff --git a/scripts/run_example.sh b/scripts/run_example.sh
index bf22f31..0cf69e6 100644
--- a/scripts/run_example.sh
+++ b/scripts/run_example.sh
@@ -20,7 +20,7 @@ mkdir build && cd build
 
 cmake .. \
     -DFFRT_EXAMPLE=ON \
-    -DFFRT_IO_TASK_SCHEDULER=ON \
+    -DFFRT_IO_TASK_SCHEDULER=OFF \
 
 make -j ffrt
 make -j
diff --git a/src/core/task.cpp b/src/core/task.cpp
index 8de623c..0acaa5f 100644
--- a/src/core/task.cpp
+++ b/src/core/task.cpp
@@ -366,7 +366,7 @@ ffrt_qos_t ffrt_get_cur_qos()
     return qos;
 }
 API_ATTRIBUTE((visibility("default")))
-int ffrt_poller_register(int fd, uint32_t events, void* data, void(*cb)(void*, uint32_t))
+int ffrt_poller_register(int fd, uint32_t events, void* data, ffrt_poller_cb cb)
 {
     ffrt_qos_t qos = ffrt_get_cur_qos();
     return ffrt::PollerProxy::Instance()->GetPoller(qos).AddFdEvent(events, fd, data, cb);
@@ -387,7 +387,7 @@ void ffrt_poller_wakeup()
 }
 
 API_ATTRIBUTE((visibility("default")))
-int ffrt_poller_register_timerfunc(int(*timerFunc)())
+int ffrt_poller_register_timerfunc(ffrt_timer_func timerFunc)
 {
     ffrt_qos_t qos = ffrt_get_cur_qos();
     return ffrt::PollerProxy::Instance()->GetPoller(qos).RegisterTimerFunc(timerFunc);
diff --git a/src/queue/serial_looper.cpp b/src/queue/serial_looper.cpp
index e9c6312..741726d 100644
--- a/src/queue/serial_looper.cpp
+++ b/src/queue/serial_looper.cpp
@@ -83,6 +83,8 @@ void SerialLooper::Run()
     while (!isExit_.load()) {
         ITask* task = queue_->Next();
         if (task) {
+            FFRT_LOGI("pick task gid=%llu, qid=%u [%s] remains [%u]", task->gid, qid_, name_.c_str(),
+                queue_->GetMapSize());
             SetTimeoutMonitor(task);
             FFRT_COND_DO_ERR((task->handler_ == nullptr), break, "failed to run task, handler is nullptr");
             QueueMonitor::GetInstance().UpdateQueueInfo(qid_, task->gid);
diff --git a/src/queue/serial_looper.h b/src/queue/serial_looper.h
index 40ad177..6f17fad 100644
--- a/src/queue/serial_looper.h
+++ b/src/queue/serial_looper.h
@@ -50,7 +50,7 @@ private:
     void SetTimeoutMonitor(ITask* task);
     void RunTimeOutCallback(ITask* task);
 
-    std::string name_ = "serial_queue_";
+    std::string name_;
     std::atomic_bool isExit_ = {false};
     task_handle handle;
     std::shared_ptr<SerialQueue> queue_;
diff --git a/src/queue/serial_queue.cpp b/src/queue/serial_queue.cpp
index ec723e2..d69a987 100644
--- a/src/queue/serial_queue.cpp
+++ b/src/queue/serial_queue.cpp
@@ -47,36 +47,40 @@ void SerialQueue::Quit()
 
 int SerialQueue::PushTask(ITask* task, uint64_t upTime)
 {
-    std::unique_lock lock(mutex_);
     FFRT_COND_DO_ERR((task == nullptr), return -1, "failed to push task, task is nullptr");
-    whenMap_[upTime].emplace_back(task);
-    if (upTime == whenMap_.begin()->first) {
-        cond_.notify_all();
+    {
+        std::unique_lock lock(mutex_);
+        whenMap_[upTime].emplace_back(task);
+        if (upTime == whenMap_.begin()->first) {
+            cond_.notify_all();
+        }
     }
-    FFRT_LOGI("push serial task gid=%llu into qid=%u [%s] succ", task->gid, qid_, name_.c_str());
+    FFRT_LOGI("push task gid=%llu to qid=%u [%s]", task->gid, qid_, name_.c_str());
     return 0;
 }
 
 int SerialQueue::RemoveTask(const ITask* task)
 {
-    std::unique_lock lock(mutex_);
     FFRT_COND_DO_ERR((task == nullptr), return -1, "failed to remove task, task is nullptr");
-    FFRT_LOGI("remove serial task gid=%llu of qid=%u [%s] enter", task->gid, qid_, name_.c_str());
-    for (auto it = whenMap_.begin(); it != whenMap_.end();) {
-        for (auto itList = it->second.begin(); itList != it->second.end();) {
-            if ((*itList) != task) {
-                itList++;
-                continue;
+    FFRT_LOGI("cancel task gid=%llu of qid=%u [%s]", task->gid, qid_, name_.c_str());
+    {
+        std::unique_lock lock(mutex_);
+        for (auto it = whenMap_.begin(); it != whenMap_.end();) {
+            for (auto itList = it->second.begin(); itList != it->second.end();) {
+                if ((*itList) != task) {
+                    itList++;
+                    continue;
+                }
+                it->second.erase(itList++);
+                // a task can be submitted only once through the C interface
+                return 0;
             }
-            it->second.erase(itList++);
-            // a task can be submitted only once through the C interface
-            return 0;
-        }
 
-        if (it->second.empty()) {
-            whenMap_.erase(it++);
-        } else {
-            it++;
+            if (it->second.empty()) {
+                whenMap_.erase(it++);
+            } else {
+                it++;
+            }
         }
     }
     FFRT_LOGD("remove serial task gid=%llu of [%s] failed, task not waiting in queue", task->gid, name_.c_str());
@@ -110,8 +114,7 @@ ITask* SerialQueue::Next()
         if (it->second.empty()) {
             (void)whenMap_.erase(it);
         }
-        FFRT_LOGI("get next serial task gid=%llu, qid=%u [%s] contains [%u] other timestamps", nextTask->gid, qid_,
-            name_.c_str(), whenMap_.size());
+        mapSize_.store(whenMap_.size());
         return nextTask;
     } else {
         uint64_t diff = it->first - now;
diff --git a/src/queue/serial_queue.h b/src/queue/serial_queue.h
index eed0bf5..7761c01 100644
--- a/src/queue/serial_queue.h
+++ b/src/queue/serial_queue.h
@@ -28,6 +28,11 @@ public:
     SerialQueue(const uint32_t qid, const std::string& name) : qid_(qid), name_(name) {}
     ~SerialQueue();
 
+    inline uint32_t GetMapSize() const
+    {
+        return mapSize_.load();
+    }
+
     ITask* Next();
     int PushTask(ITask* task, uint64_t upTime);
     int RemoveTask(const ITask* task);
@@ -39,6 +44,7 @@ private:
     bool isExit_ = false;
     const uint32_t qid_;
     std::string name_;
+    std::atomic_uint32_t mapSize_ = {0};
     std::map<uint64_t, std::list<ITask*>> whenMap_;
 };
 } // namespace ffrt
diff --git a/src/util/slab.h b/src/util/slab.h
index 2efd4f1..703bbba 100644
--- a/src/util/slab.h
+++ b/src/util/slab.h
@@ -19,14 +19,12 @@
 #include <new>
 #include <vector>
 #include <mutex>
-#include <atomic>
 #ifdef FFRT_BBOX_ENABLE
 #include <unordered_set>
 #endif
 #include <sys/mman.h>
 #include "sync/sync.h"
 #include "dfx/log/ffrt_log_api.h"
-#include "dfx/bbox/bbox.h"
 
 namespace ffrt {
 const std::size_t BatchAllocSize = 128 * 1024;
@@ -186,13 +184,9 @@ class QSimpleAllocator {
     std::mutex lock;
     std::vector<T*> cache;
     uint32_t flags = MAP_ANONYMOUS | MAP_PRIVATE;
-    uint32_t printCnt = 0;
-    std::vector<void*> mmapedAddrVec;
-    std::atomic<uint64_t> allocatedCnt {0};
 
     bool expand()
     {
-        FFRT_LOGE("DEBUG: QSimpleAllocator::expand");
         const int prot = PROT_READ | PROT_WRITE;
         char* p = reinterpret_cast<char*>(mmap(nullptr, MmapSz, prot, flags, -1, 0));
         if (p == (char*)MAP_FAILED) {
@@ -208,24 +202,11 @@ class QSimpleAllocator {
         for (std::size_t i = 0; i + TSize <= MmapSz; i += TSize) {
             cache.push_back(reinterpret_cast<T*>(p + i));
         }
-        mmapedAddrVec.push_back(reinterpret_cast<void*>(p));
         return true;
     }
 
     T* alloc()
     {
-        FFRT_LOGE("DEBUG: QSimpleAllocator::alloc");
-        ++printCnt;
-        ++allocatedCnt;
-        if (printCnt % 10 == 0) {
-            std::string info = SaveTaskCounterInfo();
-            FFRT_LOGE("DEBUG: %s", info.c_str());
-            for (int i = 0; i < mmapedAddrVec.size(); i++) {
-                FFRT_LOGE("DEBUG: mmaped addr %d, %llu", i,
-                    static_cast<uint64_t>(reinterpret_cast<uintptr_t>(mmapedAddrVec[i])));
-            }
-            FFRT_LOGE("DEBUG: cache size %llu, used size %llu", cache.size(), allocatedCnt.load());
-        }
         T* p = nullptr;
         lock.lock();
         if (cache.empty()) {
@@ -242,8 +223,6 @@ class QSimpleAllocator {
 
     void free(T* p)
     {
-        --allocatedCnt;
-        FFRT_LOGE("DEBUG: QSimpleAllocator::free");
         lock.lock();
         cache.push_back(p);
         lock.unlock();