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Journal Journal: 3d galactic map with time calculations? 8

Ok, here's an odd request. Maybe someone out there has an answer for me.

I know we've been making huge advances in mapping distant celestial bodies, their speed either across our field of view or relative direction (to or from us) with red/blue shift, etc. I was curious to if there has been any publicly available project which creates a 3 dimensional representation of that data, and allows for adjustment of time.

The way I understand it, in theory with enough data, the known universe could be collapsed (virtually) to the time of the big bang.

I've had an idea for a (fictional) story, which I'd like to be able to back up with at least something resembling factual information. For example, the Earth takes roughly 250 million years to make an orbit all the way around our galaxy (one "Galactic year"). If you were looking at Galaxy X and Galaxy Y, and for particular intervals. Imagine a line drawn from a fixed point in each Galaxy. Would it be possible to determine if the Earth (or at least a close part of our galaxy) would intersect that line, or look back to when that did happen? ... and save the supercomputer comments for some other time. :)

User Journal

Journal Journal: Slashdot comment thread life expectancy 15

I've noticed a trend lately (like in the last couple years). Comment thread lifespans are becoming shorter and shorter. I'm usually good about going back to my messages, and keeping up conversations in the thread. It seems not everyone else is.

    If anyone who programs here reads this, do your own research against the database, and see what mean life expectancy of comment threads is. I almost guarantee if you run it against all stories from the beginning, you'll see it's tapering off.
    What I have observed with my comments, even the occasional first post, is that the thread will die off at about 2 to 3 days, regardless of how interesting the conversation is getting. It seems people just aren't interested in going to older stories, which isn't surprising since it's a pain to get to older stories. Look for a story from two weeks ago. Type in some keywords in the search? No way.. Pointy-clicky through the More buttons, good luck there.

    Still, it's easy enough for people to keep up with running conversations. Well, I assume so. When we were forced into the new theme, I had to be sure my messages box was at the top left. Maybe I'm one of the few who actually set up for that, or most people are set for no notifications. Either way, it's becoming disappointing where conversations don't run their course. I don't think it's me... I have week and month long conversation threads going with friends and colleagues, even if every 3rd message (for colleagues at least) is "you are dumb, now send what we asked for". :) No offense to any colleagues or ex-colleagues who may read this. I'll assure you to your face that I'm not talking about you, but sure as hell when you aren't looking, I'm going to point at you and say "it was him".

So back to the topic... I wish more of you would keep up your ends of the conversation. It's hard talking about interesting subjects, and when I've written a well thought out reply, it's just exceeded the MTTL (mean time to live) for a thread, and it's abandon. Well, except for the random troll who goes back through old threads and writes TL;DR, but he barely counts as anything. :)

    Maybe Slashdot can gear up something more conducive to actual conversations, rather than a few hundred drive-by comments that are dead end conversations. I really miss the intellectual (or quasi-intellectual, sometimes) conversations, now replaced by a short thread lifespan and high churn of stories.

User Journal

Journal Journal: Things I learned today. Browser URL length limitations 2

For a long time, I've followed what I've read regarding URL lengths. 255 characters is it. Never let it get longer than that.

    By the RFC's, 255 characters is the guideline, to maintain backward compatibility with old browsers, old proxy servers, and other miscellaneous hardware that may be in the way.

    I went looking for more information, but found conflicting or outdated information. Who cares what the limits on Netscape 4 or MSIE 5 were.

    In my own personal MythBusters kind of way, I wanted to see what the limitations really are.

    What fun would it be without coding something up to handle it. :) I would share the code, but it seems Slashdot doesn't like that much. Basically, it would generate a URL, something like http://example.com/test.php?pad=11111 , and use a javascript redirect to send it back to itself. On receiving it, it would read the number of characters of the full URL, then add an increment to the pad. It printed the length of the request, and the full URL in the browser, so I could see where it was at. I introduced a 1 second pause so I could read the output.

    Initially my increment was 1, but that takes an awful long time, even with keepalives cranked up. I worked my way up to 500 per exchange, so the test would move along quickly. Watching the server stats, the keepalives were doing their job perfectly. The same connections were reused until their life expectancy ran out.

    I couldn't just give a redirect header. Browsers tend to not like that. My initial test with Firefox showed the problem. The default for network.http.redirection-limit is 20. Even turning that up to 999999 would stop pretty quickly (at about 500, if I remember right)

    My test client machine is a Windows 7 Ultimate machine with a Phenom II x4 955 and 8GB RAM. My test browsers are MSIE 8.0, Chrome 9.0, Firefox 3.6.13, and Safari 5.0.3. During the tests, I did not run into problems with CPU or memory utilization.

    My test server is a Slackware Linux 13.1.0 machine with two dual core Xeon 2.8Ghz CPUs and 4GB RAM. It is using Apache 2.2.17 and PHP 5.3.5. Other than custom configuration options, it's a fairly plain version of Apache and PHP. No patches. The OS is pretty clean. All non-essential ports and tasks are disabled. During the test, I did not run into any CPU or memory utilization problems.

    On the first run I observed:


        MSIE 8.0 4095
        Chrome 9.0 8190
        Firefox 3.6.13 8190
        Opera 11.01 8190
        Safari 5.0.3 8190

    I looked around a little. Apache lets you lower the length of the URL in the config file, but not increase it. The default is 8190, exactly as tested. Time to go patch Apache!

In httpd.h
/** default limit on bytes in Request-Line (Method+URI+HTTP-version) */
#ifndef DEFAULT_LIMIT_REQUEST_LINE
#define DEFAULT_LIMIT_REQUEST_LINE 16777216
#endif /** default limit on bytes in any one header field */
#ifndef DEFAULT_LIMIT_REQUEST_FIELDSIZE
#define DEFAULT_LIMIT_REQUEST_FIELDSIZE 16777216
#endif /** default limit on number of request header fields */
#ifndef DEFAULT_LIMIT_REQUEST_FIELDS
#define DEFAULT_LIMIT_REQUEST_FIELDS 16777216
#endif

    8190 was obviously set by people with no ambition. 16.7 million? That's a real URL! :) And before anyone says it, no, I wouldn't normally make the URL longer than I'm willing to type. Just like the MythBuster folks wouldn't normally put a dead pig in a car to see if it stinks. It's all in the name of science I tell you! :)

    So limits upped to 2^24, recompile complete, and we're ready to test again. While watching the compile, I had to ask myself, "does PHP have a limit too?". I guess not. Here's the results.


        MSIE 8.0 4095
        Chrome 9.0 122560
        Firefox 3.6.13 111060
        Opera 11.01 132560
        Safari 5.0.3 131060

Notes:
    1) I aborted the tests after I got bored.

    2) Chrome stopped displaying the full URL at about 32,000 characters. It truncated it at the ?, but did process correctly. If you have a 32,000 character URL, expect people to not be able to copy it from Chrome very easily. :)

    3) I started all the tests very close to the same time, and aborted them all very close to the same time. I don't normally use anything but Firefox, so I have several utility toolbars (webmastering, packet examination, and SEO analysis) that are installed. The others are clean.

    4) You can't use this as a benchmark saying any browser is faster than another, because I was limited by upload bandwidth at home.

    During the test, I was watching my uplink bandwidth graph. I'm on a residential line. It was clear where the upload bandwidth is cut off at (about 700Kbps). Due to the nature of this test, Every request was sent to the server, and returned to the browser, so like it or not I needed to use the same bandwidth each way. If I have a moment of sheer boredom at work or a datacenter sometime, I may repeat this test on a LAN. It's doubtful though.

    So in conclusion....

    1) All the modern browsers tested, except MSIE are effectively unlimited to the size of the URL they can handle.

    2) MSIE is still limited to a URL length of 4095 characters. I don't see a workaround for this.

    3) Apache is limited by default to 8190 characters, but this can be corrected with a patch.

    4) Regardless of what these components proved they could do, you can still encounter problems with firewalls, content filters, proxy servers, etc. Don't expect to be able to use over 255 characters.

User Journal

Journal Journal: 2012 Presidential Bid 5

I thought this was worthy for cross posting to my journal.

    For the 2012 election, the answer is easy.

        Write in JWSmythe!

        I promise restoration of the rights of all people, as protected by the Constitution and Bill of Rights.

        I promise transparency in our government, and open public audit of all government projects.

        I promise revocation of the Income Tax (25% of your income for most citizens), to be replaced by a 2% sales tax. This effectively gives a 23% raise to all working citizens.

        I promise increase in tariffs on foreign goods to be no less than 2% of the retail value, to encourage growth in the industrial sectors of America.

        I promise immediate closure of all tax "loop holes" to ensure all "big money" corporations pay in their fair share.

        I promise yearly "dividend" payments to the citizens of the United States on any excess tax paid by the citizens and profit from foreign tariffs.

        I promise health care in the form of open access doctors and hospitals to be no less than 25% of the total medical service field (at least 25% of doctors will be free for the citizens). You may still purchase insurance, and doctors may still provide special expert service, but for those who can't afford it, free services are available, and more positions will be available for both new and skilled doctors.

        I promise open borders, reducing the lengthy and confusing immigration/emigration procedures. Diverse and contridactory policies exist now, including Canadians who are welcome across the friendly open borders, but Mexicans who are frequently detained, arrested, or left to die in military style borders and checkpoints. This will reduce operational costs for enforcement agencies by billions yearly.

        I promise retiring the Department of Homeland Security and the Transportation Security Administration, returning their duties to the appropriate intelligence agencies. This removes over $55 billion in yearly government expenses that are simply not necessary.

        And oddly enough, I'm dead serious. I'm not a billionaire, so I cannot afford the campaign. The estimated cost for the 2008 Presidential election was $1.6 billion per candidate. Neither established party back me. I would hurt their corporate interests.

        And yes, I am an American born citizen. I have traveled to the majority of US states, and both bordering nations. I don't know everything, but I know people who I can trust who are experts in their fields. No individual can run the country properly, but a good team will return the United States to it's prior reputation of the nation all others want to emulate, rather than the most powerful and embarrassing nation in the world.

User Journal

Journal Journal: How not to transfer an OS 6

I got a fun pre-xmas present, a new Phenom II X4 955. It's a 3.4Ghz CPU that runs very happily at 4Ghz. The previous occupant in that socket was an Athlon II X4 2.8Ghz, that ran happily for a year at 3Ghz.

    I spent an hour fiddling with overclock settings, and settled at 4.2Ghz (more or less). While sitting with just the browser open, Asus Probe (temp, fan, and voltage monitor) started screaming that the core voltage was above threshold. At about 6pm, there was a thunk, and everything went dark. I'm not sure if it was the power supply or motherboard died. I had ongoing problems with the motherboard since I got it, where bios settings would mysteriously change themselves after weeks of working normally. The power supply wasn't anything spectacular, but it seemed to work. I headed down to CompUSA, and picked up a new power supply, motherboard, and I decided that the drives weren't fast enough, so I picked up a pair of 1.5Tb SATA drives to run as a RAID0. Mmm. More speed.. :)

    I got home at about 8pm. I dismantled the whole thing, and had it reassembled in about 10 minutes. Now I have two blank drives in position (ports 1 & 2), the old drive (port 4), and the DVD player (port 6). I poke around in the BIOS a bit, getting everything set right, and setting the drives as a RAID0. I boot up to a trusty Linux CD to start the transfer. Blah, the RAID controller is really a software raid. I see both disks. There are fixes, I'm just not that far yet. I decide to just copy everything to the first SATA drive, and I'll RAID other parts later. My girlfriend would like to watch a movie with me, as I set up all my theater equipment in our new "theater room" (DLP projector, 8' wide screen, 7 speakers all properly placed and tuned +- 1dB). All I have to do is get the transfer started, and go watch the movie.

    dd if=/dev/sda of=/dev/sdc bs=1024k

    Seems simple enough, right? I switch to another console, and kill -USR1 $pid , to see where it's at. 2GB transfered. Great. The partition table should already be written. fdisk -l /dev/sda shows nothing. hmmm. fdisk -l /dev/sdc shows nothing.

    Aw fuck.

    It dawns on me, I'm not cloning the old drive to the new ones, I'm cloning the empty drive over my data! ABORT ABORT ABORT!

    Well, the partition table is gone, and presumably the beginning of the drive is overwritten, so none of that will be recovered. I think I have enough crap on there to fluff it a bit. My first and second partitions were Linux, which is easily replaced. The third and fourth partition hold Windows 7 and all my current work. The fifth partition holds all my virtual machines, which are my testbed for all kinds of fun things. Employment essential aren't a big deal, they're replicated at work, and on backups there. It's things like the 5,000 pictures that I took over the years, that I reacquired from various sources, which are now almost organized to store and back up, but I haven't finished. And a few videos including a 1hr 15min video of a live band that I'm including 400 stills into to make a good video of their performance.

    With tools on the TRK, I've been able to see the partitions to recover, but since I'm not totally familiar with the particular tool, it's been a slow process. Reading across a 1Tb drive, it takes hours. Even still, I'm not totally sure I could convince Windows to clone to the array, rather than using just one drive.

    So now, I'm starting off with a fresh Windows install. The Windows installer sees the array. I'm using 1Tb for Windows (2 1.5Tb drives RAID0 = 3Tb). Once I have a working machine again, and can play WOW with my girlfriend (she likes playing it), I'll be happier, and then can repair the messed up drive overnight on a few nights.

    The only real problems I had on the old machine were that it couldn't play Stargate: Revolution (crashes after a few minutes), and I wasn't totally satisfied with the drive speed. According to the "Windows Experience Index", my scores were:

Component
Processor 7.3
Memory (RAM) 7.3
Graphics 6.6
Gaming graphics 6.6
Primary hard disk 5.9

(current "max" score is 7.9)

    When I've looked at machines in the stores, this is way above any retail box. I just wanted to get the drive speed in line with the other parts. Dammit. So it'll take a few days to get it up and working properly. Until then, I'll be limping along on the laptop. :) No video editing on the laptop though, it just isn't fast enough, even though it's only a few months old.


Processor 3.2
Memory 4.9
Graphics 3.0
Gaming graphics 4.5
Primary hard disk 5.4

User Journal

Journal Journal: Wasted humor

I hate it when I put work into humor and no one notices, so maybe some folks will notice it here. :)

    There was a story a few days ago titled Giant Planet Nine Times the Mass of Jupiter Found

    Thread, segue, tangent, and a reference to Space Panda's, I doctored up
    this photo.

    Who can't love a cute cuddly planet eating space panda?

    Too bad we can't embed images into the comments, it would have been funnier faster.

    So, enjoy. :)

User Journal

Journal Journal: My stupid purchase of the month 4

Sometimes, when I have a couple extra pennies, I buy something that just feels good to get, that is completely worthless. I'm no shopaholic, so these are usually simple things.

    I was at CompUSA and found that they had glowing keyboard stickers. Like, stickers to put over each letter, that will glow in the dark.

    I should explain, I've been touch typing for over 20 years, and can usually get 100wpm with 0 errors on most typing tests. I only slow down by thinking. People have watched me programming, typing emails or journal entries like this. A few have commented on it. I'll blaze through lines as fast as they can read, but I'll pause at spoken pauses (ummm, like commas), and when I'm thinking of what to say next.

    At home, I'm usually typing in the dark, with just the light of my monitor, and possibly a TV.

    So I got the yellow stickers (thanks everyone for asking). My shells are green or yellow text on a black background. It's enough to drive most people nuts, if they try to keep up with all my terminals. It's not usually hard. One running top. one tailing the log of most interest. one editing code, and executing it. I may have one with a man page up, and another logged into another machine to reference old code. Add one for a web browser for my email, and another for looking up something specific. So the browsers aren't green on black (except my themed gmail account is pretty close).

    I got glow in the dark bling for my keyboard. :) Ok, I'm easily entertained.

User Journal

Journal Journal: I love Amazon [tag: sarcasm] 1

I love Amazon.

    I was helping my aunt put her bookstore online. She has a used paperback store with tens of thousands of books in stock. She's been doing it for over 25 years, and the technology hasn't changed since Day 1. Literally, she's still using the same old cash register as the day she started.

    A few years ago, I suggested putting it online, and/or selling some of her overstock through eBay. I'd say Amazon, but they rape vendors on the fees. To demonstrate what I was trying to explain, I put together a warm friendly front end that would pull the book details from Amazon. It was the best source I could find for any arbitrary ISBN.

    Well, 3+ years later, she gave me the go ahead to start clearing out the back room. Great, I can start doing the inventory, and listing items. Great went to not so great. I picked up a cheap barcode scanner, and scanned the first book. I got an error back from Amazon. My API key was still valid, but they now require the requests to be signed. Digging around a little, this happened in August of 2009. I do receive emails from them, but I never saw anything regarding this. Apparently they gave their developer network 3 months to implement the signing.

    Their signing isn't quite as easy as it seems it should be. Their documentation is now focused on their cloud computing platform. The rest is sparse at best. Most of the references I found talked about how to do it before the signing, which I already mastered. I finally found someone who had posted a function that would sign the request. That took a few hours and a lot of Google searches to accomplish. What a way to support legacy apps. I found plenty of references where other folks had modules written for their software that broke on the day of the changeover. If this had been a production application, it would have been a real headache. Come on, don't change the functionality of the API without clear explanation of how to fix it.

    Now it's up and back running. I'm adding the rest of the required functionality. I could have spent the weekend adding functionality, rather than chasing down a solution to fix what they broke.

User Journal

Journal Journal: Things I learned driving at 2am 2

This is non-tech, but I thought I'd share. :)

    I learned something at 2am the other morning. Driving at night, in an unfamiliar area, isn't always the best idea. I took a guy to his place from a bar, because he was absolutely hammered. File that under "no good deed goes unpunished".

    After leaving his place, I was heading home. I bumped over something at about 20mph. It wasn't much of a bump, but I immediately heard my tires go flat. Like, a dramatic wooshing sound from both tires on one side. I stopped and looked. Sure enough, both tires were flat, but I didn't see any damage to the rims. I assumed it just damaged the tires. Maybe it was some broken glass or something in the road. I was 10 miles from home, but it was cold out, and I wasn't going to wait for a tow truck. I could drive the car, but only at 10 miles per hour. Talk about a less than entertaining drive.

    I ordered tires the next morning, and they arrived today. I pulled the two flat wheels off, so I could get the new tires mounted. As soon as I did, I saw the bad news. The inside lip of the rim was seriously bent. Like, so much that I could put my finger between the rim and the tire. No wonder they went woosh dramatically.

    I went to a few shops to see if I could get the rims fixed or replaced. I already know it's virtually impossible to find OEM replacement wheels for my car. They were exclusive to my car, and only on 3 years, on a very specific submodel, in that style. I was in a little accident in February, and the other drivers insurance company had to cough up $1000/ea for the wheels from the only place they could find them. It took weeks to get them in.

    In talking to them about the damage, they said it was clear that I hit a pothole. If it had been a loose object in the road, both wheels would not have been bent exactly the same way. If it had been a curb, the outside lip of the wheel would have been damaged. So, dumb luck on a dark road in the middle of the night.

    So, that's my rant. I am carless until after the 1st, since no one locally stocks anything that could fit, and no one is doing shipments over the holiday. {sigh}

User Journal

Journal Journal: Windows 7 Ultimate

Anyone that knows me knows, I'm a died in the wool Linux fan. I use Windows as a tool to accomplish a task. That is, if I *need* to run a Windows application, that I can't do any other way, I use Windows.

      Someone was nice enough to donate a copy of Windows 7 Ultimate to me to try out. I had been using XP Professional for my Windows work. I tried, and didn't like Vista. I've retried it several times over, and have been annoyed with it when it does stupid things. I tried a few beta's, and worked with it in normal releases on others computers.

      I had low expectations for Windows 7. I expected a freshly skinned Vista.

      The hardware I'm working on is a AMD AM3 Athlon II x4 620 (2.6Ghz) overclocked to 3Ghz. Asus motherboard, with integrated ATI Radeon HD 3300, and 2Gb of DDR3 RAM. 512Mb is shared to the video card, which I will be fixing sometime soon. This Asus board was the only one that took DDR3 that CompUSA had in stock at the local store. I figured it's easier to stay with this video card for now, and upgrade it later. I also plan the same for the CPU. I'll be purchasing an actual Phenom II x4, as the pricing comes down. I did a little reading, and this CPU overclocked does as well or better than it's Phenom II x4 sister. Hey, can't argue with that, especially with the lowest price tag in the store.

      I have Windows 7 Ultimate 64-bit in it's own partition. I can say, "well, it's not too bad." It's doesn't seem as resource hungry as Vista.

    The only things I've noticed are that there are no Vista nor 64-bit drivers for my old Linksys WUSB11. The fault there is with Linksys not making new drivers for their legacy hardware, not Microsoft It does manage my Belkin USB device well though. Well, it handles it better than XP did. I had intermittent service with it, and attributed that to the device. It works well with the 64-bit Vista drivers. The drivers don't just install themselves, like they're suppose to, so it takes a little loving to make it work. Not a big deal though, everything else went in fluidly.

    I've noticed that Win7 automatically schedules a defrag for 1am weekly. Nice touch. I changed the schedule to daily, and the time to later, when I'm less likely to be using the machine.

    Would I avoid a 64 bit version of Linux for Win7 64-bit? No.

    I noticed something funny. They keep two separate trees for x86(32) and x86(64) program files. Under Linux, with the proper libraries installed, this is unnecessary. I don't know the purpose of this. Maybe it's for organization. Maybe it's because it pays attention to the path. Maybe it just likes it that way. Either way, it seems odd.

    On a 64bit Linux (Slamd64 and now Slackware 64), I've always had almost everything compiled for 64 bit. The only glaring exception was Firefox, because there was no 64bit flash plugin. Since that was resolved months ago, I've used 64bit everything. I have run 32 bit applications, because I was testing something from a 32 bit machine. No big deal there, it just worked.

    For folks that like Windows (like most average home users), I won't scare them away from Win7 as an upgrade path. I warned people off of Vista, because I always ran into problems. It seems like they've done something mostly right this time. :) I still reserve the right to decide that it sucks, if I start running into serious problems. For now though, the install went smooth, and it's working pretty well.

    I just did another Win7 install on an older Athlon64 machine (3000+, 1Gb RAM), and performance wise it seems slightly better than XP.

    As a note, these measurements are "seat of the pants" measurements. They were not quantified with any benchmarks. Really, end users care about how good it feels, even if the benchmarks prove otherwise.

User Journal

Journal Journal: Things I Discovered Since Unemployment... 8

Here's a few insights that I've acquired since unemployment. I've been unemployed for about 3 months now, and technically homeless.

    1) Laundry is much easier to do, when all you wear is shorts and sandals. Here in Florida, it's hot, so wearing a shirt is an unnecessary evil, and just gets sweaty anyways. (and yes, I'm in shape enough to do it)

    2) Pants and socks feel funny. I actually dressed up one day and realized that all the extra clothes felt restricting. Well, and hot. I was much happier stripping down and putting just shorts back on. I'm not a nudist, I'm just practical. When it's 95 degrees out, anything you might be wearing is too much. I strongly encourage attractive women to do it too. :)

    3) People with jobs can't come out to play as often. I am job hunting, but since 20% of the population is doing the same thing, I'm not getting any positive feedback. When I want to hang out with someone who is working, I have to wait for them to get off work, and we have to stop drinking early on Sunday night. That slows down my drunken weekends, when they have to get to bed "to go to work."

    4) It can get really boring with nothing better to do. Some of you may have noticed an increase in my posting on here. Hey, I have time on my hands, in between sending off resumes, watching TV, and talking on the phone.

    5) The headhunters are desperate too. Like I said, I'm in Florida. No, I don't want my resume sent off with 100 others, for a 3 month minimum wage job as an entry level programmer in a language I don't know, that would require me moving 1,000 miles. They don't quite understand why either. I don't exactly have the budget to move anywhere. After taxes, I'll be lucky to come home with $1k/mo, and that's not going to cover rent, power, water, food, and gas. I'd also have to break my lease at the end of 3 months, which won't go over that well either.

    6) Picking up odd jobs can be fun. This month, I've:

  Worked on a dozen cars.
  Done plumbing work in a half dozen places,
  Cleaned countless computers of viruses, malware, and stupid things that slow the machine down (how many toolbars do you really need for your browsers?).
  Several days of "personal security" which consists of me owning a gun, which sat in the house, and me being there "just in case" something happened. At least they were good for conversations, or else I would have been bored out of my mind.

    In doing the odd jobs, I've found they're asking me to do them, because they can't afford a "professional" to do them. Either way, when I'm done, it's still done right. I've taken "payment" in food, cigarettes, gas, and places to sleep. I did get someone to buy me a GPS, so I won't get quite so lost in strange cities. It's neat. I no longer have to call and say "I'm at this intersection" just to find out I'm in the wrong city. :)

    All in all, I'd like to have a job again, and my own place to live. Since I haven't slept in the same place for more than about 3 days in a row, I'm getting to see a lot of places that I otherwise wouldn't have had time to. I have helped a lot of people out, and saved them a fortune. I usually tell them what the job would have cost by a "professional", and they "pay" me what they can afford, in the method that they can do it in. I've had some nice dinners in the comfort of someone elses home. :)

    It's been interesting. I'm left with $20 in my pocket and couple 2 liters of soda, and a tank full of gas.

    And as a side note, if you have work for me, I can be almost anywhere if you're paying gas, food, and a place to sleep. :) This is a long stretch from my old 6 figure job, but I am anything but stressed out these days. I have people lined up for the short term of doing things, so I won't go hungry anytime soon.

Operating Systems

Journal Journal: Adventures with a TC1000 1

As any of you who read my journal know, I was laid off a couple months ago. Nope, no luck on the job front, and no unemployment to carry me through.

    I've been picking up the odd jobs here and there, but they rarely pay for much more than cigarettes and gas. Otherwise, I've been living by the good graces of friends. If I didn't have my friends, I would have starved to death over a month ago. Thanks to all of you.

    Now, on with my journal rant. :)

    My laptop died. Well, the power jack on the back died. No power means no laptop. A friend has loaned me his old Compaq TC1000. It's a 1Ghz Transmeta with 768Mb RAM. I put a 100Gb hard drive in that I had laying around.

    I thought it would be a brilliant plan to dual boot it. WinXP on one partition, and Slackware Linux on another. It's working pretty well, but I'd like to share some comparisons.

    Both OS's are completely up to date. In the Windows world, that means it's bloated beyond use. In the Linux world, it's nice and fast.

    With XP, I've removed absolutely everything that I could find that wasn't necessary to save CPU time and memory. I did every tweak I could.

    With Slackware, I haven't tweaked it yet. I did a full install, but only enabled the essential services. I currently have it running Gnome.

    With XP, it was an interesting exercise of copying drivers to a USB drive, and then copying them onto the tablet, so I could install them. After several rounds of that, I got online. It wasn't just the network driver that needed help. There was so much to do, it took me several days to get things working almost properly.

    With Linux, the wired ethernet adapter just worked. The wireless adapter wanted a firmware binary, which I found and dropped into place. I ran into some glitches with the video driver in Xorg, but nothing show stopping. I had Linux running in a matter of about an hour, and a few more hours tweaking Xorg.

    To browse the net, say for viewing here, it was an interesting exercise.

    MSIE on XP is so slow it's unusable. Even when I'm attached to someone's wireless at a good connection, it feels like I'm on a 9600 baud connection.

    Firefox on XP is tolerable for the first few minutes, but then it ends up sucking up too much memory and CPU time. I did several tweaks, but that hasn't helped much.

    Google Chrome on XP is my answer there. It actually behaves moderately well.

    So, now Slackware.

    Even with the limited resources, Firefox on Linux performs just about as I'd expect. It can be a little slow on occasion (as is normal for a Transmeta, from what I've read), but generally it's kicking along just like it should.

    There is no offical Chrome yet, so I haven't tried.

    I was going to try some of the other browser, but haven't bothered yet.

    I'm using this tablet as my GPS also. I had purchased Garmin's MobilePC software a while back. It works in Windows fine, as long as I shut everything else down first. In Linux, it works fine under Xorg, but since it was bundled with it's own GPS receiver, it wants to see that to activate all the functions. I'm still working on that part. I found that it should work, but I haven't made it work yet.

    I'm writing this right now from the tablet, using Firefox under Linux. I had noticed that using Firefox under XP, I could type out lines, and wait for them to display. I could get up to 2 lines ahead, which is very sad. With Firefox under Linux, it's hept right up with me the whole time. That's always nice to see, since I type over 100wpm. :)

    Ok, enough of my random ramblings. If you didn't want them, you wouldn't read my journal. :)

User Journal

Journal Journal: Linux RAID performance benchmarks

  I am setting up a new server, which has to be as fast as I can make it.  Quantifiable results are king here. Hopefully this will help others out, but I strongly recommend doing your own testing on your own configuration.

  I wrote a couple scripts.  One formats the array with a specific filesystem.  The second reads and writes.  Basically (in psuedocode)

echo 0 > a
while (i < 31)
cp a b
cat b > a
end

Here are the results, sorted by speed then RAID level.  My apologies for the layout on here.  I copy&pasted it from an OpenOffice spreadsheet.

fs    raid level    format (sec)    write 1g (sec)
xfs    0    2    20
jfs    0    n/a    20
ext2    0    60    20
ext4dev    0    48    22
ext3    0    62    22
reiser    0    n/a    25
ext4    5    77    32
ext4    0    49    32
ext4    1    61    33
xfs    5    9    48
jfs    5    n/a    50
ext4dev    5    74    50
ext2    5    93    55
reiser    5    n/a    58
ext3    5    94    61
jfs    1    n/a    66
xfs    1    2    68
reiser    1    n/a    69
ext4dev    1    59    70
ext2    1    63    70
ext3    1    68    72

The same list, ordered by filesystem and then raid level.

fs    raid level    format (sec)    write 1g (sec)
ext2    0    60    20
ext2    1    63    70
ext2    5    93    55
ext3    0    62    22
ext3    1    68    72
ext3    5    94    61
ext4    0    49    32
ext4    1    61    33
ext4    5    77    32
ext4dev    0    48    22
ext4dev    1    59    70
ext4dev    5    74    50
jfs    0    n/a    20
jfs    1    n/a    66
jfs    5    n/a    50
reiser    0    n/a    25
reiser    1    n/a    69
reiser    5    n/a    58
xfs    0    2    20
xfs    1    2    68
xfs    5    9    48

The machine for this test is a dual 4 core Opteron 2350 (8 cores total) with 64Gb RAM, 3 integrated nVidia MCP55 SATA controllers, and 4 500Gb Western Digital WD5001ABYS-0 SATA drives.  The OS is a plain installation of Slamd64 12.2 (Slackware for AMD64).  uname reports:
root @ vsql2 (/proc) uname -a
Linux vsql2 2.6.27.7 #1 SMP Sun Dec 7 22:31:27 GMT 2008 x86_64 Quad-Core AMD Opteron(tm) Processor 2350 AuthenticAMD GNU/Linux

I have not customized the kernel at all, which may lead to performance increases beyond this.  This wasn't a performance test, it was a filesystem and raid comparison.  For example, better SATA drivers should improve the performance, but that should directly scale.

The RAID configuration is as follows.  Each partition is a 100Gb partition, so they're each working with the same size space.

root @ vsql2 (/proc) cat /proc/mdstat
Personalities : [linear] [raid0] [raid1] [raid10] [raid6] [raid5] [raid4] [multipath]
md1 : active raid1 sdd2[2] sdc2[1] sdb2[0]
      104864192 blocks [3/3] [UUU]

md2 : active raid5 sdd3[2] sdc3[1] sdb3[0]
      209728384 blocks level 5, 64k chunk, algorithm 2 [3/3] [UUU]

md0 : active raid0 sdd1[2] sdc1[1] sdb1[0]
      314592576 blocks 64k chunks

unused devices: <none>

User Journal

Journal Journal: Gas combustion expansion rates and golfball cannon 3

I was entertained looking at "spud guns". That is, guns that shoot potatoes. My thoughts went from potatoes to more interesting, and regular sized objects.

    I found a site talking about piercing a solid wood door (by mistake) with a tennis ball. Oops. :) I was thinking more life golf balls.

    One site I found claimed that with propane and atmospheric air, they achieved double the speed of sound (680 m/s or 1522 mph). That sounded unrealistic.

    So I was wondering, what are the combustion expansion rates of various available gasses. I figured with the intelligent people on here, someone may know.

    Propane and atmospheric air doesn't seem ideal. Most of the information I read pointed out a problem. After a single shot, the had to vent the combustion chamber, or it wouldn't fire again (not enough oxygen).

    So, here's my theoretical ideas.

    Propane/Oxygen, like from a small torch set available at any hardware store.

    MAPP gas/Oxygen

    Hydrogen/Oxygen, electrolyzed from water.

    Atomized gasoline and atmospheric air.

    Atomized aviation fuel (110LL) and NOS. :) Ok, I'm going a little overboard, and would probably blow the combustion chamber.

    Any are easily accessible, and could have good results, without the need to vent the chamber after each shot.

    I guess the other obvious question would be about the volume of expansion of the gas before combustion is complete. I saw some pictures of people using hair spray with an 8' barrel. I can't imagine the combustion created enough expansion to utilize that space, so it would actually slow it down towards the end of the barrel. I know properly sized firearms use the right size barrel, so the combustion is just almost finished by the time the bullet leaves the end of the barrel. Too much flash means there was still fuel to burn. No flash means the barrel was too long.

    This is all theoretical. I live in a lovely deed restricted residential community. I know any will go "BOOM" really nicely, so the neighbors may just complain a little. I'm just bothered that I couldn't find the combustion expansion properties of the gases.

    But someday, it may be fun to make one. :) I liked model rocketry and miniature blackpowder cannons as a kid, so this is just an extension of that. How can I make something go fast. :)

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