Use one buffer for recover
Use one buffer for recover

00k/ToyDFS,myawan/bfs-1,bluebore/bfs,baidu/bfs,lylei/dfs,yvxiang/dfs,myawan/bfs-1,baidu/bfs,yvxiang/coverage_for_bfs,baidu/bfs,linyvxiang/dfs,lylei/dfs,yvxiang/dfs,yvxiang/dfs,bluebore/dfs,linyvxiang/dfs,myawan/bfs-1,bluebore/bfs,lylei/dfs,lylei/dfs,yvxiang/coverage_for_bfs,linyvxiang/dfs,bluebore/dfs,yvxiang/coverage_for_bfs,yvxiang/dfs,myawan/bfs-1,bluebore/dfs,00k/ToyDFS,baidu/bfs,yvxiang/coverage_for_bfs,bluebore/bfs