The Transition to Ext4

I’ve been investigating the Ext4 filesystem [1].

The main factor that is driving me to Ext4 at the moment is fsck times. I have some systems running Ext3 on large filesystems which I need to extend. In most cases Ext3 filesystems have large numbers of Inodes free because the relationship between the number of Inodes […]

Finding Thread-unsafe Code

One problem that I have had on a number of occasions when developing Unix software is libraries that use non-reentrant code which are called from threaded programs. For example if a function such as strtok() is used which is implemented with a static variable to allow subsequent calls to operate on the same string then […]

Per-process Namespaces – pam-namespace

Mike writes about his work in using namespaces on Linux [1]. In 2006 I presented a paper titled “Polyinstantiation of directories in an SE Linux system” about this at the SAGE-AU conference [2].

Newer versions of the code in question has been included in Debian/Lenny. So if you want to use namespaces for a login […]

Things you can do for your LUG

A Linux Users Group like most volunteer organisations will often have a small portion of the membership making most of the contributions. I believe that every LUG has many people who would like to contribute but don’t know how, here are some suggestions for what you can do.

Firstly offer talks. Many people seem to […]

Debugging as a Demonstration Sport

I was watching So You Think You Can Dance [1] and thinking about the benefits that it provides to the dancing industry. The increase in public appreciation for the sport will increase the amount of money that is available to professionals, and getting more people interested in dancing as a profession will increase the level […]

Swapping to a Floppy Disk

In the mid 90’s I was part-owner of a small ISP. We had given out Trumpet Winsock [1] to a large number of customers and couldn’t convert them to anything else. Unfortunately a new release of the Linux kernel (from memory I think it was 2.0) happened to not work with Trumpet Winsock. Not wanting […]

A Basic IPVS Configuration

I have just configured IPVS on a Xen server for load balancing between multiple virtual hosts. The benefit is not load balancing but management. With two virtual machines providing a service I can gracefully shut one down for maintenance and have the other take the load. When there are two machines providing a service a […]

The History of MS

Jeff Bailey writes about the last 26 years of Microsoft [1]. He gives Microsoft credit for “saving us from the TRS 80”, however CP/M-86 was also an option for the OS on the IBM PC [2]. If MS hadn’t produced MS-DOS for a lower price then CP/M would have been used (in those days CP/M […]

The New OLPC

TED has a post about the design of the new OLPC [1].

I never liked the previous OLPCs [2], for my use a machine needs a better keyboard than the tiny rubber thing that they had. I understand why they designed it that way, for use in places where it would be an expensive asset […]

Ideas to Copy from Red Hat

I believe that the Red Hat process which has Fedora for home users (with a rapid release cycle and new versions of software but support for only about one year) and Enterprise Linux (with a ~18 month release cycle, seven years of support, and not always having the latest versions) gives significant benefits for the […]