diff --git a/lib/tasks/statistic_subject_info.rake b/lib/tasks/statistic_subject_info.rake
index d39e1fe86..ccca9d28b 100644
--- a/lib/tasks/statistic_subject_info.rake
+++ b/lib/tasks/statistic_subject_info.rake
@@ -7,9 +7,11 @@ namespace :subjects do
     subjects = Subject.where(status: 2, hidden: 0)
     column_value = "subject_id, study_count, course_study_count, initiative_study, passed_count, course_used_count, " +
         "school_used_count, created_at, updated_at"
-    subjects.find_in_batches(batch_size: 50) do |s|
+    Parallel.in_processes(4) do |i|
       str = []
-      Parallel.each_with_index(s, in_processes: 4) do |subject, index|
+      puts("Parallel.worker_number: #{Parallel.worker_number}")
+      subjects.find_in_batches(start: (Parallel.worker_number/4) * subjects.count,
+                               finish: ((Parallel.worker_number+1)/4) * subjects.count) do |subject|
         puts("---------------------data_statistic: #{subject.id}")
         Rails.logger.info("---------------------data_statistic: #{subject.id}")
         data = Subjects::DataStatisticService.new(subject)
@@ -22,15 +24,40 @@ namespace :subjects do
             "'#{Time.now.strftime('%Y-%m-%d %H:%M:%S')}', '#{Time.now.strftime('%Y-%m-%d %H:%M:%S')}')")
         puts "index: #{index}; worker_number: #{Parallel.worker_number}"
         puts "####str: #{str}"
-        if str.size == 100 || subject == s.last
+        if str.size == 50 || subject == s.last
           sql = "REPLACE INTO subject_records(#{column_value}) VALUES #{str.uniq.join(",")}"
           puts sql
           ActiveRecord::Base.connection.execute sql
           str = []
         end
       end
+
     end
-    if buffer_size > 0
+
+    # subjects.find_in_batches(batch_size: 50) do |s|
+    #   str = []
+    #   Parallel.each_with_index(s, in_processes: 4) do |subject, index|
+    #     puts("---------------------data_statistic: #{subject.id}")
+    #     Rails.logger.info("---------------------data_statistic: #{subject.id}")
+    #     data = Subjects::DataStatisticService.new(subject)
+    #     study_count = data.study_count
+    #     next if study_count == 0
+    #     course_study_count = data.course_study_count
+    #     initiative_study = study_count - course_study_count
+    #     str << ("(#{subject.id}, #{study_count}, #{course_study_count}, #{initiative_study}, " +
+    #         "#{data.passed_count}, #{data.course_used_count}, #{data.school_used_count}, " +
+    #         "'#{Time.now.strftime('%Y-%m-%d %H:%M:%S')}', '#{Time.now.strftime('%Y-%m-%d %H:%M:%S')}')")
+    #     puts "index: #{index}; worker_number: #{Parallel.worker_number}"
+    #     puts "####str: #{str}"
+    #     if str.size == 100 || subject == s.last
+    #       sql = "REPLACE INTO subject_records(#{column_value}) VALUES #{str.uniq.join(",")}"
+    #       puts sql
+    #       ActiveRecord::Base.connection.execute sql
+    #       str = []
+    #     end
+    #   end
+    # end
+    if str.size > 0
       sql = "REPLACE INTO subject_records(#{column_value}) VALUES #{str.uniq.join(",")}"
       puts sql
       ActiveRecord::Base.connection.execute sql