Oracle Linux 6 DVDs Now Available

On Sunday 6 February 2011, Oracle Linux 6 was released on the Unbreakable Linux Network for customers with an Oracle Linux support subscription. Shortly after that, the Oracle Linux 6 RPMs were made available on our public yum server. Today we published the installation DVD images on edelivery.oracle.com/linux. Oracle Linux 6 is free to download, install and use. The full release notes are here, but similar to my recent post about Oracle Linux 5.6, I wanted to highlight a few items about this release.

Unbreakable Enterprise Kernel

As is the case with Oracle Linux 5.6, the default installed kernel on x86_64 platform in Oracle Linux 6 is the Unbreakable Enterprise Kernel. If you haven't already, I highly recommend you watch the replay of this webcast by Chris Mason on the performance improvements made in this kernel.

       # uname -r         2.6.32-100.28.5.el6.x86_64 

The Unbreakable Enterprise Kernel is delivered via the package kernel-uek:

  [root@localhost ~]# yum info kernel-uek         ...         Installed Packages         Name       : kernel-uek         Arch       : x86_64         Version    : 2.6.32         Release    : 100.28.5.el6         Size       : 84 M         Repo       : installed         From repo  : anaconda-OracleLinuxServer-201102031546.x86_64         Summary    : The Linux kernel         URL        : http://www.kernel.org/         License    : GPLv2         Description: The kernel package contains the Linux kernel (vmlinuz), the core of                    : any Linux operating system.  The kernel handles the basic functions                    : of the operating system: memory allocation, process allocation,                    : device input and output, etc.  

ext4 file system

The ext4 or fourth extended filesystem replaces ext3 as the default filesystem in Oracle Linux 6.

   # mount         /dev/mapper/VolGroup-lv_root on / type ext4 (rw)         proc on /proc type proc (rw)         sysfs on /sys type sysfs (rw)         devpts on /dev/pts type devpts (rw,gid=5,mode=620)         tmpfs on /dev/shm type tmpfs (rw,rootcontext="system_u:object_r:tmpfs_t:s0")         /dev/sda1 on /boot type ext4 (rw)         none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw) 

Red Hat compatible kernel

Oracle Linux 6 also includes a Red Hat compatible kernel built directly from RHEL source. It's already installed, so booting it is a matter of editing /etc/grub.conf

        # rpm -qa | grep kernel-2.6.32         kernel-2.6.32-71.el6.x86_64 

Oracle Linux 6 no longer includes a Red Hat compatible kernel with Oracle bug fixes. The only Red Hat compatible kernel included is the one built directly from RHEL source.

Yum-only access to Unbreakable Linux Network (ULN)

Oracle Linux 6 uses yum exclusively for access to Unbreakable Linux Network. To register your system with ULN, use the following command:

              # uln_register 

No Itanium Support

Oracle Linux 6 is not supported on the Itanium (ia64) platform.

------

近日，Oracle发布了Oracle Linux 6版本，在 Unbreakable Linux Network上显示的日期是2011年2月11日，现在这个版本已经可以下载，按照Oracle的一贯说法，这一版本可以 " free to download, install and use"，其版本信息参考 here。

该发布的内核版本是2.6.32，缺省使用Ext4文件系统，从Wiki百科摘录以下Ext4的特性：

ext4（第四扩展文件系统）文件系统是Linux系统下的日志文件系统，是ext3文件系统的后继版本。

ext4 原始的开发目标是一系列的向下兼容ext3、移除其64位限制与提升其效能的延伸包[1]。然而，某些Linux开发者因稳定性原因而拒绝将这些延伸包应用在ext3上，并要求其作为ext3的分支，改名为ext4并另行开发，以免影响到目前的ext3用户。该要求被接受以后，ext3维护者 Theodore Ts'o在2006年6月28日公开了ext4的开发计划。

ext4文件系统可支持最高1 Exbibyte的分区区与最大16 Tebibyte的文件

Ext4另外一个引人的变化是引入了Extent的文件存储方式，这一概念和Oracle中的Extent概念非常相似了：

ext4 引进了Extent文件存储方式，以取代ext2/3使用的block mapping方式。Extent指的是一连串的连续实体block，这种方式可以增加大型文件的效率并减少分裂文件。ext4支持的单一Extent，在单一block为4KB的系统中最高可达128MB。单一inode中可存储4笔Extent；超过四笔的Extent会以Htree方式被索引。

新部署的系统完全有必要来体验一下Oracle Linux 6的内核了,也可以利用一下Oracle Public YUM Server！

-The End-