SunRay Server 3.0 Beta available for download

Thursday Aug 12, 2004

As Jason Shroeder's Weblog points out, SunRay Server 3.0 beta is now available for download here. It runs on Linux or Solaris and has low bandwidth requirements (300kb/sec), which makes it possible to run it over broadband. I've been using it for a while now.

Suspicious object

Wednesday Aug 11, 2004

I think I know what happened in Racine Wisconsin [Racine Journal Times] which led to the destruction of an electromechanical blogging device. An article in Forbes indicated that DYI retailer "Home Depot" would recycle used electronics equipment. Forbes probably meant "Office Depot", an electronics retailer down the street from "Home Depot." So a misguided soul left his portable electric typewriter in the parking lot outside of Home Depot, hoping it would be recycled. Perhaps the employees had never seen such a device and couldn't imagine why it would be abandoned outside of their store. So the local police were called and the strange object was destroyed. Now I need to figure out how to get rid of my old Remington in Racine without raising suspicion.

Persistence of technology... Part 2: Sustainable hardware

Tuesday Aug 10, 2004

Like many science techies, I like to keep up with the latest technology. But I also have a concern for the environment. So I end up with a museum of old computers in my basement and attic. I hate to put them in a landfill, yet what can I do with them? Fortunately a few electronics recycling organizations have been founded and some manufacturers have offered to bear the cost of recycling consumer electronics. In addition to this, software such as the linux terminal server project allows new uses for old x86 hardware.

But that's solving the problem after the fact. Is it possible to design long lasting computer hardware? I have heard legends of a particular company's server running unmaintained in a bricked over wiring closet for years. Should we expect hardware to last 25 years or at least 10? Is it too much to expect that our computer's case and power supply can be reused for two Moore's law doublings or at least through the next OS upgrade? Some companies rely on proprietary standards and planned obsolescence to force customer upgrades before they would otherwise be necessary. But shouldn't consumers demand the ability to upgrade components, software and services without having to visit the landfill every eighteen months? Moore's observation has held over the past couple of decades, but as this curve flattens and disposal costs increase, it will become less cost effective to replace hardware on such a short time scale.

When we need a brighter or more efficient light we don't have to replace the lamp or light fixture we just replace the bulb. Twenty years ago we expected this level of servicability from other appliances. We could give a television a new life by replacing a $10 tube. Individual components were much less reliable but the end product tended to last longer. Today a blown $1 fuse or dead battery is likely to mean that your treasured piece of technology will end up in a local landfill mountain or polluting the devloping world

Open Standards

My career as a "desktop mechanic" started in a surplus electronic parts store and progressed to the servicing of Zenith 286 PC hardware. These computers used a passive backplane which made it possible to repair or upgrade video, CPUs, disk controllers and memory by simply swapping cards. There was no need to replace the case or motherboard. But when bus standards and case form factors changed these computers were also condemed to the landfill. Open standards are the key to sustainable hardware. Imagine if the internet were based on a proprietary protocol which was tied to a single vendor's OS and hardware. That vendor would have incentive to frequently change or "upgrade" the protocol but each change could force millions of consumers to replace their hardware.

The sustainable computer

How would I design a computer that minimised its landfill footprint? When I wrote this a couple of weeks ago I wasn't sure it was worth publishing. I thought maybe no one else would care about this. But now I see that the hyper transport motherboard in Sun's new Java workstations appears to be designed for modular expansion. And Sun isn't stopping here. What if there were no motherboard at all but instead a collection of electronic scrabble tiles that fit together to make a computer. If you needed a bigger cache or faster CPU, just replace a tile. Someday maybe you'll only have to recycle a 2 centimeter semiconductor square that weighs a couple of grams instead of a 30kg box.

Yet another green advantage to ultra thin clients

I've been using a SunRay as my primary work desktop since I began working at Sun in the spring of 2001. I think they're one of the coolest bits of technology we have and I was happy to learn that they use very little electricity when compared to the typical desktop P.C. But when I started to think about designing a sustainable IT infrastructure it struck me that ultra-thin clients are ideal. When Sun Ireland upgrades to a new OS, do we send a bunch of these to the landfill? Heck no, the sysadmin upgrades the OS or software on the server, the clients do not change at all! When we want to upgrade hardware, can just add another CPU or more storage to the existing server. There's seldom need to swap out old server hardware and there is certainly no need to swap out clients! In the unlikely event that we decide to upgrade the clients, instead of scrapping hundreds huge boxes full of fans, heavy metals, 300W power supplies, motors, wires and gears... we recycle a little box with no moving parts. Any organization which uses SunRay servers can immediately reuse another company's SunRay clients by simply plugging them into their own corporate network.

I'm not sure whether to put this entry in the Environment or the Sun category. I think it's pretty cool that it would fit into both!

What happened to WORLD Wide Web?

Monday Aug 09, 2004

It was about half past forever o'clock last night. My wife was beginning to design a patchwork quilt. Her quilt software was built for Microsoft Windows 3.1 but was compatible with newer versions. So I brought our windows 98 machine out of storage, dusted it off and hooked it up. I reluctantly asked if she needed it on the web. I was dreading the number of reboots that would be required to install every security patch since the machine was last powered up. No, she said she would look up what she needed to on the Powerbook. So I left the appropriate air gap between the Windows 98 machine and the broadband modem and continued reading "The Far Side of the World." Only minutes later she encountered a problem. "It says 'This website must be viewed with Netscape 4.7'" What?! I've encountered dozens of websites which only work properly with Internet Explorer, some which refuse to work without a specific version of Macromedia Flash (not the newer version that is on the Mac) and a few which refuse to work on anything but Windows 98 running a specific version Internet Explorer. I've even encountered airline websites with browser specific bugs in its leap year calcuating code. But this is the first time I've encountered a website which required a version of Netscape from the previous millenium.

Can we agree on this one thing?

I hope users of Apple OSX, OS9, RedHat, SuSE, Debian, FreeBSD, Solaris and the various versions of Microsoft windows can agree that the world wide web should be as open and accessible as possible. As far as I'm concerned, websites which are hard-coded to a particular distribution and/or browser are broken. Whenever possible I try to gently notify webmasters of these problems. I hope others do the same. In most cases they are happy for the feedback. Most well run businesses strive to be accessible to as many customers as possible. Now that people are beginning to switch from Internet Explorer to more secure and powerful browsers such as Mozilla, Firebird and Safari, we need to encourage web designers to use tools such as Bobby to indicate whether a website meets accessibility and W3C standards. We don't design our roads for a particular brand of car, nor do we design our telephone, television, or radio communications to be brand specific. Wherever possible, the world wide web should also be a standards based platform neutral communications medium.

Will it scale? (Back of the envelope calculation)

Thursday Aug 05, 2004

Hmm, there are only 8 users on this machine, but quite a few open files:

# lsof | wc -l
  36844

A fair number of processes:

# ps -ef | wc -l
    472

and how many threads?

# ps -m m
ps: error: Thread display not implemented.

Uh oh. How do I find out how many threads are in use? Well it looks like ps -ef actually shows threads so 472 is the approximate number of threads (and the process count isn't accurate!)

So, as I scale up users with this usage pattern, would I bump into the thread limit first or the process table limit, or the number of open files? Or something else? The linux 2.4 kernel FAQ gives:

       /*
         * The default maximum number of threads is set to a safe
         * value: the thread structures can take up at most half
         * of memory.
         */
        max_threads = mempages / (THREAD_SIZE/PAGE_SIZE) / 2;

# sysctl kernel.threads-max
kernel.threads-max = 14336

or alternatively:

# cat /proc/sys/kernel/threads-max
14336

And how many open files can the linux reiser filesystem handle:

# ulimit -n
1024

1024? That can't be right, I already have 36844 files open! Further googling revealed that ulimit -n gives the per process limit. The system maximum for open files is the third number in:

# cat /proc/sys/fs/file-nr
11991   1267    412819

That's about 11 times what 8 users are currently using. So the filesystem limit is a respectable 88 users.

What is the thread limit?

threads-per-user=current-threads/8 = 472/8 = 59
max-users= threads-max/threads-per-user = 14336/59

That's about 242 users. I wonder what other limits are lingering out there? Does anyone have a nice table of limits for various operating systems? I know many are configurable but I'd be interested in the out of the box "supported" limit the absolute theoretical limits for various Linux distributions and Solaris. Be very quiet, I'm hunting limits...

Update

I took this offline for a while because I didn't want anyone skimming the blog and coming to the conclusion that "Sun says I can run 242 users on a X86 linux box." But today I found myself referring to it so maybe it could be useful to someone else.

On second thought: Tadpole Comet would make a nice iWork client

Wednesday Aug 04, 2004

O.K. a powerful 64 bit workstation might be overkill for some iWorkers. Thanks Dan for pointing out another iWork option: The new low bandwith SunRay protocol over DSL with one of these cute little Tadpole Comet thin client laptops. Since the battery doesn't have to run a space heater and cooling fan or peltier device, this Tadpole can get 6-8 hours off a single battery! This would be great for libraries, schools, businesses and eventually for the rest of us. (When the world is "wired" for WiFi.)

If a thin client future sounds unlikely think of this: Broadband and WiFi bandwidth continues to increase while thin client bandwidth requirements decrease. Also the same thing happened with audio communication. While you could use a powerful 1000 Watt amateur radio or 4 Watt CB radio to wirelessly contact a neighbor, most of us find it more convenient and reliable to use a 0.25 - 2 watt cell phone and let the network do the work. Sure there will still be power users with thick clients in their bedroom just as there are still radio hams and muscle car enthusiests. But I'm writing this blog from a SunRay1 thin client on a 100MBs ethernet and for most applications it already feels much faster than my 2.8 Ghz P4 laptop.