4. Filesystems and Storage updates
In the 5.4 update, several significant additions have been made to file systems support. Base Red Hat Enterprise Linux now includes the
Filesystem in Userspace (FUSE)
kernel modules and user space utilities, allowing users to install and run their own FUSE
file systems on an unmodified Red Hat Enterprise Linux kernel (BZ#457975). Support for the XFS
file system has also been added to the kernel for future product enablement (BZ#470845). The FIEMAP input/output control (ioctl) interface has been implemented, allowing the physical layout of files to be mapped efficiently. The FIEMAP ioctl can be used by applications to check for fragmentation of a specific file or to create an optimized copy of a sparsely allocated file (BZ#296951).
另外,在内核中更新了通用互联网文件系统(CIFS)(BZ#465143)。更新了 ext4 文件系统(在红帽企业版 Linux 中作为技术预览出现)(BZ#485315)。
在红帽企业版 Linux 5.4 这,全局文件系统 2(GFS2)作为单一服务器文件系统使用(例如:不在群集的环境中)已经过时。不需要高可用性群集的 GFS2 用户可考虑迁移到其它文件系统,比如 ext3 或者 xfs。xfs 文件系统是特别用于超大文件系统的(16TB 或以上)。将会支持现有用户。
要求的语义指出某个完成
stat, write, stat
的进程应该看到来自第二个 stat 调用的结果文件的 mtime
(最后一次修改的时间)与来自第一个 stat 调用的结果的 mtime
不同。NFS 中的文件时间由该服务器严格管理,因此文件 mtime
不会更新直到使用 WRITE NFS
协议操作将该数据传送到服务器为止。仅仅将数据复制到页缓冲中还不足以更新 mtime
。这是 NFS 与本地文件系统的一个不同之处。因此,有大量写入工作负载的 NFS 文件系统可能出现 stat 调用等待。(BZ#469848)
已经使用更新的用户空间工具刷新了 ext4 文件系统技术预览。Ext4 是在由红帽以及 Linux 社区开发的 ext3 文件系统基础上的改进。
注意
之前的红帽企业版 Linux 采用 ext4 作为技术预览,将 ext4 文件系统标记为
ext4dev
。在这个更新中,现已将 ext4 文件系统标记为 ext4
。
With this update, the
(BZ#512833)
dmraid
logwatch-based email reporting feature has been moved from the dmraid-events
package into the new dmraid-events-logwatch
package. Consequently, systems that use this dmraid feature will need to complete the following manual procedure:
- ensure the new 'dmraid-events-logwatch' package is installed.
- un-comment the functional portion of the
/etc/cron.d/dmeventd-logwatch
crontab file.
samba3x and ctdb are provided as a Technology Preview on the x86_64 platform. Samba3x package provides Samba 3.3 and ctdb provide a clustered TDB backend. Running samba3x and ctdb on a set of cluster nodes with GFS file system will allow the export of a clustered CIFS filesystem.
重要
the samba3x packages conflict with the samba-3.0 packages shipped with Red Hat Enterprise Linux 5. To use the Technology Preview, it is recommended to perform a fresh install that does not include the samba-3.0 packages, and then to install the samba3x packages from the Supplementary media.