Linus Torvalds as the father of Linux operating system announced the release of Linux 3.0 on Thursday, July 21, 2011.
According to Linus, in the new version “there are no special landmark features or incompatibilities related to the version number change, it’s simply a way to drop an inconvenient numbering system in honor of twenty years of Linux. In fact, the 3.0 merge window was calmer than most, and apart from some excitement from RCU I’d have called it really smooth. Which is not to say that there may not be bugs, but if anything, there are hopefully fewer than usual, rather than the normal “.0” problems.”
The Linux 3.0 comes to bring several new features including Btrfs data scrubbing and automatic defragmentation, XEN Dom0 support, wake on WLAN features and more.
Btrfs lays out the data sequentially when files are written to the disk for first time, but a copy-on-write design implies that any subsequent modification to the file must not be written on top of the old data, but be placed in a free block, which will cause fragmentation. The auto defragmentation detects small random writes into files and queues them up for an automatic defrag process, so the filesystem will defragment itself while it’s used.
Though Xen has been a long running in the Linux kernel, however we need to firstly patch the kernel to run the Xen. With the Xen dom0 support on Linux 3.0, we do not need to patch the kernel for Xen anymore since the stock support is already in the kernel.
More details about the Linux 3.0 features and improvements can be found at http://kernelnewbies.org/Linux_3.0