In　order　to　study　how　to　strengthen　the　real-time　support　of　Linux　operating　system,　some　weaknesses　of　the　process　scheduler　of　the　2.4　kernel　are　discusses.　Owing　to　the　lack　of　real-time　support,　the　system　can　not　guarantee　that　the　real-time　tasks　be　responded　and　scheduled　in　time.　The　2.4　kernel　is　not　enough　to　the　multiprocessor　support.　This　paper　analyses　the　principles　and　implementing　details　of　process　scheduler　in　the　2.6　kernel.　Compared　with　the　2.4　kernel,　the　2.6　kernel　strengthens　the　support　of　real-time　tasks　and　multiprocessor　environment,　implements　the　O(1)　scheduling　algorithm　and　preemption.　The　article　also　describes　some　improvement　in　the　2.6　kernel　on　response　time　and　system　spending.　The　prominence　characteristics　of　the　2.6　process　scheduler　are　to　support　preemption　and　the　loading　balance　of　multiprocessor　etc.,　so　it　can　be　used　in　the　real-time　environment.