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| Asgard | ||||||||||||||
| February 11th, 2010 at 11:32 AM | ||||||||||||||
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The new machine is complete! Asgard:
PHOTOS:
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| New Skin, New Classes |
| January 26th, 2010 at 3:39 AM |
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Yeah, new skin. Same layout as the old skin but not red, and not fixed-width font. I'm not sure I like this better, but it does have some nice improvements. So, a new semester is upon me. With work and all, I'm taking a lighter courseload -- just 14 hours of classes:
CS 473 is what I'm really looking forward to. I have grand plans to develop a groundbreaking C compiler with super secret technology of my own design, so this class will provide me with the necessary knowledge to do hard-core compiler work (hopefully). I'm already learning how to do parsing properly, and it's been an interesting exercise to thoroughly analyze the skin parsing code for this site, which I wrote in high school when I knew nothing about formal parsing theory, and see what I got right. Surprisingly, I got quite a bit of it right. w00t! EAES 101 is about rocks and stuff. Sleepytime. Actually, we got into global weather patterns today, which was pretty interesting. But mostly this class is about rocks, so I struggle to stay awake. However, it has possibly the easiest lab section ever, and it fulfills my lab sci requirement, so SCORE. ECON 121 is turning out to be a fascinating class. The professor is one of the most enthusiastic teachers I've ever had, which is very good because our textbook and the subject matter in general are quite dry. I'm really getting into this course. Who knows, maybe I'll learn enough to become a brilliant economist and make a killing in the stock market. Yeah right. Very useful knowledge nonetheless. That's about all I've got. Things at work are mostly super-secret right now, so I won't broach that subject, but I'll just say that I'm having a good amount of fun, so Good Times. _WRF |
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| Semi-Scientific Filesystem Comparison |
| January 12th, 2010 at 6:34 PM |
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System: Dual Pentium III (Coppermine) @ 1000 MHz / 133 MHz FSB, 2 GiB ECC SDRAM. Linux 2.6.32-ARCH. Disks: four 10,000 RPM UltraSCSI 320 disks in RAID5 (hardware accelerated). Max read speed: ~50 MB/s. Max write speed: ~35 MB/s Setup: filesystems created on a 10 GiB (10737418240 bytes) zero-filled file, mounted via loop device. Test 1: unpack an uncompressed tar archive of the Chromium browser source code at revision 35890 (2.6 GiB, 222964 files) to the test filesystem. Test 2: delete all files created in test 1. (Note: CPU usage is out of 200%, and the loop device and tar command make up a large part of it) JFS Test 1: 3:25.85, 32% CPU JFS Test 2: 0:22.38, 64% CPU XFS Test 1: 4:22.26, 43% CPU XFS Test 2: 1:16.31, 89% CPU Ext4 Test 1: 3:28.61, 28% CPU Ext4 Test 2: 0:24.12, 72% CPU ReiserFS Test 1: 4:28.20, 39% CPU ReiserFS Test 2: 0:33.93, 91% CPU So, JFS wins this one, which is good, because that's what filesystem I'm already using. :) Test procedure: |
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| Re: An Interesting Processor Comparison |
| October 10th, 2009 at 4:33 AM |
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Aha. Figured out why the AthlonXP beats the pants off the Core Duo. Too many processes. The Core Duo seems to be much slower at creating new processes, which my test method did a lot of. Also, with the fact that so many short-lived processes are flying around, and therefore being shuttled back and forth between the two cores, these cores' caches probably aren't being used very well, causing even more slowdown. In the end, I rewrote my processing shell scripts as one program (a PHP script :P), and the processing time on the Core Duo went from 20 minutes down to a few seconds. Clearly, the new-process overhead is significant. The other machines saw similar improvements, to the point where I can't really tell which machine is fastest, because the script runs so fast. |
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| An Interesting Processor Comparison | ||||||||||||||||||||
| October 9th, 2009 at 11:22 PM | ||||||||||||||||||||
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My latest Computer Science assignment involved a large amount of number crunching and text processing, and seeing as how I have a large assortment of computers around my apartment, I figured I'd try them all out and see how they stacked up. The results proved quite surprising. The data I needed to process was a large text file (10680 lines), where each line had a source IP address, a destination IP address, and various network statistics. I wrote two scripts to process this: the first took each IP address, looked it up in a file that mapped IPs to latitude-longitude pairs (816 lines long), and printed lines with the address substituted for the location. The second script took these two locations and calculated the distance on the globe between them. Script #1, for each input line, grep'd the ip-location map twice (once for source, once for dest), and printed the new line with the IPs substituted for locations.Script #2, for each line, ran a perl script that used the Math::Trig module to compute the great circle distance between the locations, and printed the new line with the locations substituted for the distance between them.These scripts were run as a pipeline, so as to take advantage of dual-core processors: The Machines
Yes, that's correct. The Core Duo was more than THREE TIMES SLOWER than the old crusty AthlonXP at this test, despite being able to take full advantage of the parallellized script, being dual-core. For the life of me, I can't figure out why. Both AMD machines are using DDR ram, whereas the Core Duo is using faster DDR2. The Core Duo has 2MB of on-chip cache, the Athlon64 has 1MB, and the AtlonXP only has 256K. It just goes to show how good those AMD processors are. I often rip on that AthlonXP as being the hottest-running chip I've ever seen (it regularly hits 60+ degress Celcius at idle), but it's still plenty good at doing things that matter. |
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| Shoutbox |
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Anonymous:
lonely shoutbox :( April 7th, 2008 at 7:09 PM |
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Anonymous:
hello April 7th, 2008 at 7:12 PM |
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Anonymous:
o hai April 28th, 2008 at 2:31 PM |
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CHIZUBAGA:
I CAN HAZ CHIZUBAGA!!!!!!! January 20th, 2010 at 2:58 PM |
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Not Jeremy:
o hai remember when i threw hot sauz in yer eye. lulz January 28th, 2010 at 1:28 PM |
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JEREMY:
MOAR NAPKINS DURR HURR February 11th, 2010 at 11:33 AM |
