Friday, October 06, 2006

A Developer's Journal: Solaris/CMT #7

I got the answers I was looking for:

Solaris has major releases every 2 - 3 years and minor releases every 3 - 6 months S10 is the current major release.


The updates have major features integrated. To move from Update to Update you usually re-install the OS. You download the CD image or put it on your install server. You can opt for a Upgrade option as well. In between updates there are patches. These fix problems with a variety of products. There is one patch in particular called the kernel jumbo that has many of the fixes for just the OS. These can be downloaded from There are mandatory patches to fix panics etc. These are available for free download. Others require a support contract.

A Developer's Journal: Solaris/CMT #6

I'm back in Solaris mode and I've hit a wall. Solaris 10 is Unix and that's great because visa-vi GNU/Linux I am very comfortable with Unix. Before I got my hands on my box I made the decision not for force my GNU/Linux habits onto Solaris because its probably a recipe for pointless frustration. So I'm very interested in learning the Solaris way of doing things. The issue I'm struggling with right now is patching and versioning. I don't understand how they fit together as a whole. Now I know I just said I wasn't going to force my GNU/Linux habits onto Solaris but I need to do a little compare and contrast to ensure that I'm asking the right question.

In Gentoo there is no explicit concept of a version. There are live CD releases such as 2006.1 or 2006.2 but you can't use that as a mechanism for discussing the version of Gentoo that's actually running on your box because as soon as you run emerge --sync && emerge -uD world or build your own kernel the whole version concept breaks down.

At the other extreme is Windows. You buy a copy of Windows of a specific version and it stays that way until Microsoft releases a new version and you explicitly purchase and install the new version. In the interim the most you can do is apply hot fixes and service packs. So to move from WinXP to Vista I would have to buy Vista and install clean or do an upgrade of my current WinXP install.

So which one is Solaris most like? Gentoo or Windows? Because I'm trying to get from Solaris 10 1/06 to 6/06 and I'm not sure how to get there.

Thursday, October 05, 2006

Throw more threads at it

Why Events Are A Bad Idea (for high-concurrency servers)

An interesting position paper on why parallel programming using threads are better for highly concurrent servers compared to event based approaches. Even though the paper is 3+ years old its more applicable now than it was then in large part because threads have gotten cheaper. How so?

  • High performance thread libraries are part of the Linux kernel since 2.6 (NPTL) and the Solaris 10 kernel both of whom implement a 1x1 model.
  • As memory performance and bandwidth increases the cost of context switches decreases. As a matter of fact reducing the cost of a context switch is baked into the DNA of Sun's Niagara family of processors. AMD had the bright (right) idea to include the memory controller right on the chip. They also switched to a NUMA topology which boosts performance when the data is closer to where it's needed. Intel and IBM continue to increase on chip cache sizes to reduce the frequency and thus the latency associated with having to fetch data from main memory.
  • Massively parallel super computer on a chip is around the corner. Check out:

I could go on but I'll stop here. Click on the link, read the paper, and draw your own conclusions.

Sunday, October 01, 2006

OpenBSD needs our help

Dear Reader,

I hope to appeal to your sense of decency and fairness in requesting that you support OpenBSD's ongoing campaign to get Intel to provide open access to the documentation (and in some cases binary blobs) behind their wireless chipsets [full story here]. This access will not only benefit OpenBSD but all FLOSS operating systems and strengthen the ecosystem by giving us (you and me) more choices from a hardware and operating system perspective.

Please stop buying Intel's products if possible and at a minimum send emails to and voice your concerns. The Internet gives you a voice and I implore you to use it.