Tag: Linux kernel

Fedora 22 released with GCC5, Kernel 4.0 and more

Anoop C SLeave a comment

f22

Now that Fedora 22(f22) has been released officially, we can all run the latest kernel version i.e, v4.0.4 which is present there by default. This particular post is intended to spread some light over the changes during the transition from fedora 21(f21) to 22. The following points are explained from my experience with the latest version after up-gradation. When version 21 was released, I followed the fedup procedure. Since the up-gradation was successful, I decided to do fedup for version 22 too and it doesn’t disappoint me in any aspect. In fact at first attempt it complained about the lack of disk space on my laptop and I had to do a massive clean-up to recover some free space. I wonder why it requires too much of disk space. Post installation steps were really helpful in building the rpm database so that future errors can be avoided.

DNF or YUM: Do they differ?
I would say no for this question because I couldn’t find any major difference. They could have announced that we are renaming yum to dnf. Instead they made dnf as an advanced yum and for an end-user its pretty much the same thing. One important thing to notice here is that its super fast in resolving the dependencies and parallel downloading of packages. I really loved this improvement as it took more time for yum previously. Being said that, dnf is not Read More »

Compiling Linux kernel with Rich ACL support

Anoop C SLeave a comment

I don’t know how many of you have heard about Rich ACL or Rich Access Control Lists. Most of you might have heard about NFS protocol i.e, the Network File System protocol. This particular protocol, with its v4.0 and above defines a particular set of ACLS known as NFSv4 ACLs. Rich ACL is a modified or an extended form of NFSv4 ACLs. Let me explain in brief on what do we mean by ACLs.

ACL or Access Control List ?
This is a list of permissions attached to an object. The object can be file, directories and so on. An ACL specifies which users or system processes are granted access to objects, as well as what operations are allowed on given objects.

ACLs and Linux
Linux follows the POSIX 1003.1e draft 17 standard for defining and storing ACLs. Even then in linux, getfacl and setfacl command line utilities do not strictly follow POSIX 1003.2c draft 17, which shows mostly in the way they handle default ACLs. For detailed explanation on how ACLs are defined and how they work in linux, please see http://users.suse.com/~agruen/acl/linux-acls/online/ .

Variations in ACL implementations
The ACL model implemented by the various versions of Windows is more powerful and complex than POSIX ACLs, and differs in several aspects. These differences create interoperability problems on both sides which is a disadvantage for UNIX-like systems. To address this issue, several UNIX-like systems started to support additional ACL models based on version 4 of the the Network File System (NFSv4) protocol specification. Linux is lacking this support so far. Following are some of the differences between various ACLs

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Linus Torvalds Announces Linux Kernel 3.12 Release!

Anoop C SLeave a comment

TuxIn a mailer sent on November 3, Linus Torvalds has announced the release of Linux kernel 3.12. The latest release comprises support for offline deduplication in Btrfs, performance improvements for AMD Radeon graphics, automatic GPU switching for the laptops with dual GPUs, improved RAID-5 multicore performance, improvements in treatment of out-of-memory situations, developments in the timerless multitasking mode, improvements in locking performance for virtualized guests, addition of separate modesetting and rendering device nodes in the graphics DRM layer, improvisation in XFS directory recursion scalability, addition of new drivers and many other miscellaneous improvements and bug fixes.

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