Wikipedia's effect on software marketing

Recently I saw a presentation from a very skilled Microsoft guy about Cloud computing. He was really good at presenting the message, telling about the cloud, about Microsoft products etc., but his terminology definitions definitely differed from mine.

Immediately, I looked up cloud computing on wikipedia, which corresponded very well with my own perception of the concept. Several years ago, I was in charge of a hosting center with a cloud computing system. It was basically just a hosting system, where multiple customers shared a PC, but it was able to move customers from one computer to another, when more power was necessary. It was nowhere as smart as the systems we have today, but to the customer, it was a dynamically scalable resource provided as a service over the internet. Some may say that cloud computing requires the ability to scale above what one server can deliver, but seriously, that's just a service specification, and for many users it is irrelevant.

If you look into existing corporate data centers, you can also see other kinds of "Cloud systems" - for instance, big VMware servers running a large number of virtual servers. To the departments, that buy these servers, and access them via TCP/IP, it is a style of computing that is dynamically scalable, virtualized and provided as a service over the internet protocol. The users/customers don't need to have knowledge of, expertise in, or control over the technology infrastructure in this system, that supports them. The VMware systems can move a virtual server from one physical server to another, moving the IP address etc. without interrupting online services and without closing TCP connections.

Does the term cloud computing describe the VMware system? Maybe. Or maybe not. But Google Engine or Windows Azure is not a revolution - to some people it's not even new stuff. 10 years ago, Microsoft may have hijacked the term and changed it to its own favor. Today, they can bend it, but not as much as before. Online, updated definitions of terminology, like wikipedia, make this a lot more difficult. I am sure that the definition of cloud computing will change in the near future, to specifically include systems in your own data center, but the new thing is, that the definition will be changed by nerds, using a common reference in wikipedia. It will not be changed by a single company's marketing department.

Use RAM disk for many small temporary files

Many systems use small temporary files to exchange information between two applications. There can be many reasons to do so: To support network file shares, to have a queue system that is not tied to any kind of special software, or simply to keep specifications simple. There are many well known examples of this, including mail systems like sendmail and postfix.

The problem is, that most Windows computers use the NTFS file system, which supports journaling. This means that every file that is created, actually activates the physical harddisk. On a system with a load, this can cause serious latency, which slows down any system. Unfortunately, it is not possible to turn off journaling for a single directory.

The solution? Install a RAM disk. It may take a part of your system's RAM, but it's surely extremely fast at creating and deleting files. You can get a RAM disk here. If you want to see performance numbers, see this page (use Google Translate for English version).

Mark D. Hill on Amdahl's law in the Multicore Era

This is a really cool video if you're interested in multi-core CPU architectures, performance, parallel programming or just want to know what Google is doing these days.