NFS のマウントオプションに関するメモ - ablogac / noac Selects whether the client may cache file attributes. If neither option is specified (or if ac is specified), the client caches file attributes. To improve performance, NFS clients cache file attributes. Every few seconds, an NFS client checks the server's version of each file's attributes for updates. Changes that occur on the server in those small intervals remain undetected until the
NFSの更新間隔（キャッシュの影響） | 日々雑感、覚書
10.3. NFS でのキャッシュの使用 | Red Hat Product Documentation
