I'm back!

Spent the day setting up more or less the same collection of PC's in the new office. The Internet connection will only be up and running on Monday but then I will be back in the game!

No more crunching ... for a while

I am currently packing up to relocate interstate, so far two of the office machines have been turned off and packed up including their annoyingly large and heavy UPS. In the next three days the "farm" will be progressively turned off. I am currently 3356th in the world rankings but I guess that will sink quickly.
At this stage, I'm not sure what the future holds in the way of crunching but I'm sure I will be back in the not-too-distant future ... hopefully with some new and efficient hardware (I can dream, can't I?)


“I'm leaving because the weather is too good. I hate Sydney when it's not raining.” ... apologies to Groucho Marx

Ubuntu/Realtek work-around

I got both machines working this morning with this combination of events:

1. Disconnect all network devices and delete all connection settings in the Network Manager applet.
2. Turn off PC, disconnect power supply and wait for about 10 seconds to ensure that residual voltage on the motherboard is gone.
3. Put a 10/100Mb/s hub between the affected PC and the giganet hub
4. Reboot and choose "Auto eth" on the manager applet.

This isn't a permanent or elegant solution but it will get you up and running if you need to.

Realtek Gigabit Ethernet LAN

Just when I am really impressed with Ubuntu, I have run into a problem on two machines, one is running 10.04LTS and the other is on 10.10. Both machines have Realtek Gigabit Ethernet LAN cards built onto the motherboards and use the r8169 driver.
In both cases, the ethernet port is just not active. I spent some time on the forums and it appears to be a well documented problem but there are very few solutions. The strange thing is that the machine that now runs 10.10 used to run 10.04 and  eth0 worked fine at 1000Mb/s. After the upgrade ... nothing!
The machine that currently runs 10.04LTS dual boots with Windows 2000 and the NIC works fine under Windows, although only at 100Mb/s.
This is a pain as I am now using USB to ethernet converters and they are s-l-o-w

BOINC with ATI on x64 Ubuntu

I mentioned in a previous post that I could not get the version of BOINC available on Synaptic to recognize the ATI GPU on my 64-bit 10.04 Ubuntu machine. If I downloaded and installed the same version of BOINC from the BOINC website, it worked fine but had to be manually started. I upgraded to 10.10 and after doing some reading on the forums, the following sorted it out:

In /etc/default/boinc-client set the user to "root"
# The BOINC core client will be started with the permissions of this user.
BOINC_USER="root"

All sorted out now ... apart from the same problem I have with the CUDA cards that it occasionally still doesn't see the GPU at start-up. This can be corrected by adding a "sleep" line to the start-up script.

Edit: I have just noticed that the ATI card in question now only reports a peak of 50GFLOPS instead of 100GFLOPS as it did under the last installation ... weird!

Difference due to operating system

I have a PC in our workshop area that needs to run Windows 2000 to remain compatible with some older production equipment. I noticed that the OS doesn't even support SSE2 and hence this machine can't run any AQUA work units. I set up a dual boot with the current Ubuntu 64-bit desktop as the second OS. I am surprised at the difference in speeds this has highlighted for a single-core Celeron chip:

Windows 2000:
Measured floating point speed:    1512.17 million ops/sec
Measured integer speed:    2385.3 million ops/sec

Ubuntu 10.04 LTS:
Measured floating point speed    1309.06 million ops/sec
Measured integer speed    5868.99 million ops/sec

I will run a couple of CUDA work-units at some stage (probably Collatz as they appear to be fairly consistent) and see how the 8600GT GPU differs due to OS.

Edit: Under Ubuntu, on average Collatz CUDA work-units are 36% SLOWER than under Windows

10 Million ....

Finally reached the 10Million Cobblestone mark this morning, a couple of days earlier than I expected thanks to the recent abundance of AQUA Fokker-Planck work-units.