diff --git a/src/sf_binlog_writer.c b/src/sf_binlog_writer.c
index 6f3a3cb..aa294f5 100644
--- a/src/sf_binlog_writer.c
+++ b/src/sf_binlog_writer.c
@@ -430,20 +430,23 @@ static void binlog_wbuffer_destroy_func(void *element, void *args)
 
 int sf_binlog_writer_init_normal_ex(SFBinlogWriterInfo *writer,
         const char *data_path, const char *subdir_name,
-        const char *file_prefix, const int buffer_size,
-        const int64_t file_rotate_size, const bool call_fsync)
+        const char *file_prefix, const int max_record_size,
+        const int buffer_size, const int64_t file_rotate_size,
+        const bool call_fsync)
 {
     memset(writer, 0, sizeof(*writer));
     writer->order_by = SF_BINLOG_WRITER_TYPE_ORDER_BY_NONE;
     return sf_file_writer_init(&writer->fw, data_path, subdir_name,
-            file_prefix, buffer_size, file_rotate_size, call_fsync);
+            file_prefix, max_record_size, buffer_size,
+            file_rotate_size, call_fsync);
 }
 
 int sf_binlog_writer_init_by_version_ex(SFBinlogWriterInfo *writer,
         const char *data_path, const char *subdir_name,
-        const char *file_prefix, const uint64_t next_version,
-        const int buffer_size, const int ring_size,
-        const int64_t file_rotate_size, const bool call_fsync)
+        const char *file_prefix, const int max_record_size,
+        const uint64_t next_version, const int buffer_size,
+        const int ring_size, const int64_t file_rotate_size,
+        const bool call_fsync)
 {
     int bytes;
 
@@ -462,7 +465,8 @@ int sf_binlog_writer_init_by_version_ex(SFBinlogWriterInfo *writer,
     binlog_writer_set_next_version(writer, next_version);
     writer->flush.in_queue = false;
     return sf_file_writer_init(&writer->fw, data_path, subdir_name,
-            file_prefix, buffer_size, file_rotate_size, call_fsync);
+            file_prefix, max_record_size, buffer_size,
+            file_rotate_size, call_fsync);
 }
 
 int sf_binlog_writer_init_thread_ex(SFBinlogWriterThread *thread,
diff --git a/src/sf_binlog_writer.h b/src/sf_binlog_writer.h
index c01f13c..2ea8091 100644
--- a/src/sf_binlog_writer.h
+++ b/src/sf_binlog_writer.h
@@ -112,31 +112,33 @@ extern "C" {
 
 int sf_binlog_writer_init_normal_ex(SFBinlogWriterInfo *writer,
         const char *data_path, const char *subdir_name,
-        const char *file_prefix, const int buffer_size,
-        const int64_t file_rotate_size, const bool call_fsync);
+        const char *file_prefix, const int max_record_size,
+        const int buffer_size, const int64_t file_rotate_size,
+        const bool call_fsync);
 
 int sf_binlog_writer_init_by_version_ex(SFBinlogWriterInfo *writer,
         const char *data_path, const char *subdir_name,
-        const char *file_prefix, const uint64_t next_version,
-        const int buffer_size, const int ring_size,
-        const int64_t file_rotate_size, const bool call_fsync);
+        const char *file_prefix, const int max_record_size,
+        const uint64_t next_version, const int buffer_size,
+        const int ring_size, const int64_t file_rotate_size,
+        const bool call_fsync);
 
 int sf_binlog_writer_init_thread_ex(SFBinlogWriterThread *thread,
         const char *name, SFBinlogWriterInfo *writer, const short order_mode,
         const int max_delay, const int max_record_size, const bool
         use_fixed_buffer_size, const bool passive_write);
 
-#define sf_binlog_writer_init_normal(writer,  \
-        data_path, subdir_name, buffer_size)  \
+#define sf_binlog_writer_init_normal(writer, data_path, \
+        subdir_name, max_record_size, buffer_size)      \
     sf_binlog_writer_init_normal_ex(writer, data_path, subdir_name, \
-            SF_BINLOG_FILE_PREFIX, buffer_size, \
+            SF_BINLOG_FILE_PREFIX, max_record_size, buffer_size,    \
             SF_BINLOG_DEFAULT_ROTATE_SIZE, true)
 
-#define sf_binlog_writer_init_by_version(writer, data_path,   \
-        subdir_name, next_version, buffer_size, ring_size)    \
-    sf_binlog_writer_init_by_version_ex(writer, data_path, subdir_name, \
-            SF_BINLOG_FILE_PREFIX, next_version, buffer_size, \
-            ring_size, SF_BINLOG_DEFAULT_ROTATE_SIZE, true)
+#define sf_binlog_writer_init_by_version(writer, data_path, subdir_name, \
+        max_record_size, next_version, buffer_size, ring_size)           \
+    sf_binlog_writer_init_by_version_ex(writer, data_path, subdir_name,  \
+            SF_BINLOG_FILE_PREFIX, max_record_size, next_version,        \
+            buffer_size, ring_size, SF_BINLOG_DEFAULT_ROTATE_SIZE, true)
 
 #define sf_binlog_writer_init_thread(thread, name, \
         writer, max_delay, max_record_size) \
@@ -151,8 +153,8 @@ static inline int sf_binlog_writer_init_ex(SFBinlogWriterContext *context,
         const bool call_fsync)
 {
     int result;
-    if ((result=sf_binlog_writer_init_normal_ex(&context->writer,
-                    data_path, subdir_name, file_prefix, buffer_size,
+    if ((result=sf_binlog_writer_init_normal_ex(&context->writer, data_path,
+                    subdir_name, file_prefix, max_record_size, buffer_size,
                     SF_BINLOG_DEFAULT_ROTATE_SIZE, call_fsync)) != 0)
     {
         return result;
diff --git a/src/sf_file_writer.c b/src/sf_file_writer.c
index cf4255b..ad0b850 100644
--- a/src/sf_file_writer.c
+++ b/src/sf_file_writer.c
@@ -236,9 +236,8 @@ static int do_write_to_file(SFFileWriterInfo *writer,
         if (fsync(writer->file.fd) != 0) {
             result = errno != 0 ? errno : EIO;
             logError("file: "__FILE__", line: %d, "
-                    "fsync to binlog file \"%s\" fail, "
-                    "errno: %d, error info: %s",
-                    __LINE__, writer->file.name,
+                    "fsync to binlog file \"%s\" fail, errno: %d, "
+                    "error info: %s", __LINE__, writer->file.name,
                     result, STRERROR(result));
             return result;
         }
@@ -296,6 +295,26 @@ int sf_file_writer_flush(SFFileWriterInfo *writer)
     return result;
 }
 
+int sf_file_writer_fsync(SFFileWriterInfo *writer)
+{
+    int result;
+
+    if ((result=sf_file_writer_flush(writer)) != 0) {
+        return result;
+    }
+
+    if (fsync(writer->file.fd) == 0) {
+        return 0;
+    } else {
+        result = errno != 0 ? errno : EIO;
+        logError("file: "__FILE__", line: %d, "
+                "fsync to binlog file \"%s\" fail, errno: %d, "
+                "error info: %s", __LINE__, writer->file.name,
+                result, STRERROR(result));
+        return result;
+    }
+}
+
 int sf_file_writer_get_indexes(SFFileWriterInfo *writer,
         int *start_index, int *last_index)
 {
@@ -365,10 +384,34 @@ int sf_file_writer_deal_versioned_buffer(SFFileWriterInfo *writer,
     return 0;
 }
 
+int sf_file_writer_save_buffer(SFFileWriterInfo *writer, const int length)
+{
+    int result;
+
+    if (writer->cfg.file_rotate_size > 0 && writer->file.size +
+            SF_BINLOG_BUFFER_PRODUCER_DATA_LENGTH(writer->binlog_buffer) +
+            length > writer->cfg.file_rotate_size)
+    {
+        if ((result=sf_file_writer_flush(writer)) != 0) {
+            return result;
+        }
+    }
+
+    writer->binlog_buffer.data_end += length;
+
+    if (SF_BINLOG_BUFFER_PRODUCER_BUFF_REMAIN(writer->binlog_buffer) <
+            writer->cfg.max_record_size)
+    {
+        return sf_file_writer_flush(writer);
+    } else {
+        return 0;
+    }
+}
+
 int sf_file_writer_init(SFFileWriterInfo *writer, const char *data_path,
         const char *subdir_name, const char *file_prefix,
-        const int buffer_size, const int64_t file_rotate_size,
-        const bool call_fsync)
+        const int max_record_size, const int buffer_size,
+        const int64_t file_rotate_size, const bool call_fsync)
 {
     int result;
     int path_len;
@@ -385,6 +428,7 @@ int sf_file_writer_init(SFFileWriterInfo *writer, const char *data_path,
         return result;
     }
 
+    writer->cfg.max_record_size = max_record_size;
     writer->cfg.call_fsync = call_fsync;
     writer->cfg.file_rotate_size = file_rotate_size;
     writer->cfg.data_path = data_path;
diff --git a/src/sf_file_writer.h b/src/sf_file_writer.h
index b9b9d09..8567e24 100644
--- a/src/sf_file_writer.h
+++ b/src/sf_file_writer.h
@@ -68,8 +68,8 @@ extern "C" {
 
 int sf_file_writer_init(SFFileWriterInfo *writer, const char *data_path,
         const char *subdir_name, const char *file_prefix,
-        const int buffer_size, const int64_t file_rotate_size,
-        const bool call_fsync);
+        const int max_record_size, const int buffer_size,
+        const int64_t file_rotate_size, const bool call_fsync);
 
 void sf_file_writer_destroy(SFFileWriterInfo *writer);
 
@@ -81,12 +81,28 @@ int sf_file_writer_deal_versioned_buffer(SFFileWriterInfo *writer,
 
 int sf_file_writer_flush(SFFileWriterInfo *writer);
 
+int sf_file_writer_fsync(SFFileWriterInfo *writer);
+
+#define SF_FILE_WRITER_DATA_END_BUFF(writer) (writer)->binlog_buffer.data_end
+#define SF_FILE_WRITER_CURRENT_DATA_VERSION(writer) \
+    (writer)->last_versions.pending
+#define SF_FILE_WRITER_NEXT_DATA_VERSION(writer) \
+    ++((writer)->last_versions.pending)
+
+int sf_file_writer_save_buffer(SFFileWriterInfo *writer, const int length);
+
 static inline void sf_file_writer_set_flags(
         SFFileWriterInfo *writer, const short flags)
 {
     writer->flags = flags;
 }
 
+static inline void sf_file_writer_set_call_fsync(
+        SFFileWriterInfo *writer, const bool call_fsync)
+{
+    writer->cfg.call_fsync = call_fsync;
+}
+
 static inline int64_t sf_file_writer_get_last_version_ex(
         SFFileWriterInfo *writer, const int log_level)
 {
diff --git a/src/sf_ordered_writer.c b/src/sf_ordered_writer.c
index 4635c5b..bf0755c 100644
--- a/src/sf_ordered_writer.c
+++ b/src/sf_ordered_writer.c
@@ -250,8 +250,8 @@ int sf_ordered_writer_init_ex(SFOrderedWriterContext *context,
 {
     int result;
     if ((result=sf_file_writer_init(&context->writer.fw, data_path,
-                    subdir_name, file_prefix, buffer_size,
-                    file_rotate_size, call_fsync)) != 0)
+                    subdir_name, file_prefix, max_record_size,
+                    buffer_size, file_rotate_size, call_fsync)) != 0)
     {
         return result;
     }