diff --git a/io/aio-wrapper.cpp b/io/aio-wrapper.cpp
index 6a33c6ec..29654095 100644
--- a/io/aio-wrapper.cpp
+++ b/io/aio-wrapper.cpp
@@ -38,10 +38,10 @@ limitations under the License.
 
 namespace photon
 {
-    const uint64_t IODEPTH = 2048;
+    constexpr static int IODEPTH_MAX = 2048;
     struct libaio_ctx_t
     {
-        int evfd = -1, running = 0;
+        int evfd = -1, running = 0, iodepth = 32;
         io_context_t aio_ctx = {0};
         thread* polling_thread = nullptr;
         condition_variable cond;
@@ -152,8 +152,8 @@ namespace photon
     static void resume_libaio_requesters()
     {
 retry:
-        struct io_event events[IODEPTH];
-        int n = HAVE_N_TRY(my_io_getevents, (0, IODEPTH, events));
+        struct io_event events[IODEPTH_MAX];
+        int n = HAVE_N_TRY(my_io_getevents, (0, IODEPTH_MAX, events));
         for (int i=0; i<n; ++i)
         {
             auto piocb = (libaiocb*)events[i].obj;
@@ -166,7 +166,7 @@ namespace photon
                          VALUE(piocb->u.c.buf), VALUE(piocb->u.c.resfd));
             thread_interrupt((thread *)events[i].data, EOK);
         }
-        if (n == IODEPTH)
+        if (n == IODEPTH_MAX)
         {
             thread_yield();
             goto retry;
@@ -347,6 +347,7 @@ namespace photon
             if (!libaio_ctx)
                 return 0;
             LOG_INFO("reset libaio by reset handle");
+            auto iodepth = libaio_ctx->iodepth;
             close(libaio_ctx->evfd);
             libaio_ctx->evfd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
             if (libaio_ctx->evfd < 0) {
@@ -355,7 +356,8 @@ namespace photon
             }
             io_destroy(libaio_ctx->aio_ctx);
             libaio_ctx->aio_ctx = {0};
-            int ret = io_setup(IODEPTH, &libaio_ctx->aio_ctx);
+            int ret = io_setup(iodepth < IODEPTH_MAX ? iodepth : IODEPTH_MAX,
+                               &libaio_ctx->aio_ctx);
             if (ret < 0) {
                 LOG_ERROR("failed to create aio context by io_setup() ", ERRNO(), VALUE(ret));
                 exit(-1);
@@ -376,7 +378,8 @@ namespace photon
         if (ctx->evfd < 0)
             LOG_ERRNO_RETURN(0, -1, "failed to create eventfd");
 
-        int ret = io_setup(iodepth < IODEPTH ? iodepth : IODEPTH, &ctx->aio_ctx);
+        int ret = io_setup(iodepth < IODEPTH_MAX ? iodepth : IODEPTH_MAX,
+                           &ctx->aio_ctx);
         if (ret < 0)
         {
             LOG_ERROR("failed to create aio context by io_setup() ", ERRNO(), VALUE(ret));
@@ -388,6 +391,7 @@ namespace photon
         assert(ctx->polling_thread);
         libaio_ctx = ctx.release();
         libaio_ctx->running = 1;
+        libaio_ctx->iodepth = iodepth;
         if (reset_handler == nullptr) {
             reset_handler = new AioResetHandle();
         }
diff --git a/io/aio-wrapper.h b/io/aio-wrapper.h
index 1f0e660f..3e18d3ae 100644
--- a/io/aio-wrapper.h
+++ b/io/aio-wrapper.h
@@ -24,7 +24,7 @@ namespace photon
 {
     extern "C"
     {
-        int libaio_wrapper_init(int iodepth = 2048);
+        int libaio_wrapper_init(int iodepth = 32);
         int libaio_wrapper_fini();
 
         // `fd` must be opened with O_DIRECT, and the buffers must be aligned
diff --git a/photon.cpp b/photon.cpp
index 331538c8..5d7dd566 100644
--- a/photon.cpp
+++ b/photon.cpp
@@ -53,7 +53,7 @@ int init(uint64_t event_engine, uint64_t io_engine, const PhotonOptions& options
         use_pooled_stack_allocator();
     }
     if (options.bypass_threadpool) {
-        set_bypass_threadpool(options.bypass_threadpool);
+        set_bypass_threadpool(true);
     }
 
     if (vcpu_init() < 0)
diff --git a/photon.h b/photon.h
index 440841cb..963afa2e 100644
--- a/photon.h
+++ b/photon.h
@@ -49,7 +49,7 @@ const uint64_t INIT_IO_DEFAULT = INIT_IO_LIBCURL;
 #undef SHIFT
 
 struct PhotonOptions {
-    int libaio_ctx = 2048;
+    int libaio_ctx = 32;
     bool use_pooled_stack_allocator = false;
     bool bypass_threadpool = false;
 };
@@ -61,7 +61,7 @@ struct PhotonOptions {
  */
 int init(uint64_t event_engine = INIT_EVENT_DEFAULT,
          uint64_t io_engine = INIT_IO_DEFAULT,
-         const PhotonOptions& options = PhotonOptions());
+         const PhotonOptions& options = {});
 
 /**
  * @brief Destroy/join ancillary threads, and finish the main thread.