The new version sees a number of important changes affecting graphics drivers. The x32-ABI promises the advantages of x86-64-CPUs without the overhead of 64-bit code. Btrfs is reported to be quicker, and Yama prevents processes from accessing each other's allocated memory.
The kernel developers have needed only two months to complete the recently published 3.4 version of the Linux kernel; yet, the release offers the usual number of new features. Some of the features are as interesting for data centre administrators as they are for users who run Linux on desktop PCs or notebooks.
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Architecture & Infrastructure
From Linux 3.4, kernels that are compiled for x86-64/x64 processors can offer an "x32" ABI (Application Binary Interface) to programs (1 and others). Programs compiled for this ABI can access the 64-bit registers and data paths of 64-bit processors, but they only use 32-bit pointers – which are sufficient for many typical tasks and use less memory than 64-bit pointers. Broadly speaking, this allows programs that are compiled for the x32 ABI to avoid the overhead that comes with full 64-bit operation while enabling them to benefit from some of the major advantages of 64-bit x86 processors. The new ABI appears to be intended predominantly for the embedded and mobile markets, as most of the programs used in this area are unlikely to require more than 4GB of memory, or they will gain enough from using 64-bit pointers elsewhere to compensate for the increased memory consumption of full 64-bit operation.