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Journal Journal: Star Trek meets Candyland 5


The other day my family was playing Candyland. Our daughter was getting into it so I started playing some classic Star Trek fight music.
The music ends just as she advances to GLORIOUS VICTORY!

YouTube video here

It's awesome, not that I'm biased... :)
User Journal

Journal Journal: Running commands on many remote hosts using ssh and xargs 3

There are a few different ways to run commands on groups or clusters of remote nodes, depending upon how complex the command.

Assuming your machines are named "node01" - "node10" :

# Run a command in parallel on all remote nodes
# results come back in random order as they are received.
pdsh â"w "node[01-22]" df

# pdsh allows some more complex listings of hosts
pdsh â"w "node04,node[06-09]" reboot

# Run a command sequentially on all remote nodes
# slow, but results come back in order
seq â"w 1 22 | xargs â"I '{}' ssh node'{}' df

# Run a command in parallel on all remote nodes without pdsh
seq â"w 1 22 | xargs â"P 22 â"I '{}' ssh node'{}' df

# Run a command in parallel needing pipes on the remote host
# Otherwise, pipes are processed locally
seq â"w 1 22 | xargs â"P 22 â"I '{}' ssh node'{}' \
"ps afx > \`hostname\`.txt"

# Run a command in parallel needing root
# sudo requires a tty, hence we pop up xterm windows
seq â"w 1 22 | xargs â"P 22 â"I '{}' xterm â"e \
"ssh -t node'{}' sudo gdm-restart"

# Run a command in parallel needing root and pipes on the remote host
seq â"w 1 22 | xargs â"P 22 â"I '{}' xterm â"e \
"ssh -t node'{}' sudo bash â"c \"echo 3 > /proc/sys/vm/drop_caches\""

User Journal

Journal Journal: Using readahead to speed up disk loading times of any application

Here's a way to get a list of files read by any application, so you can use readahead to preload those files optimally from disk:

CMD=firefox
strace -fe open $CMD 2>&1 | sed 's/.*open("\(.*\)".*/\1/' > $CMD.preload

# you can sift through that $CMD.preload file to look for things that don't belong

readahead $CMD.preload # preloads all those files into cache

time $CMD # should now start quite a bit faster, without much disk activity

## to clear disk cache as root (useful for testing / benchmarking)
echo 3 > /proc/sys/vm/drop_caches

If it works, you might want to append the contents of the .preload files for your commonly-used apps to /etc/readahead.d/default.later , so they are automatically loaded on startup (RAM size permitting)

User Journal

Journal Journal: First troll defending Linux Desktop?

Well shit. Never did I believe here on Slashdot, I would get a troll for a frank expression on Linux. Wonders abound it seems.

I've been in and around here for a very, very long time. The troll is actually funny. I won a bet on that one, BTW. Now I can go collect! Thanks for that.

I've thought about the state of open software off and on for many, many years. I think we've a clear case of a self-fulfilling reality happening with Linux Desktops. The current state of the computing industry mostly ignores the movers and shakers in favor of ordinary users doing what users do. Some of that happens on a Linux desktop, a lot of it doesn't, but does that mean the desktop is dead?

No! If you look out in the embedded space, just as one example, there is a TON of Linux. Most of those users run --wait for it! The Linux desktop! That kind of thing happens on a Linux system, just a safety tip from your buddy potatohead.

Now, maybe saying the word "fuck" got me the troll rating. Really? Come on folks! This isn't disneyland --or is it? You all tell me.

Finally, the core thing to remember about the growing body of open source software is all about the use value. For those who make the investment to make use of the open software tools, their use value and their skills are not mapped to closed things, and that value goes off the charts.

That's not gonna change for a percentage share metric published on some industry rag, filled with a lot of people, who don't actually understand the power of multi-user computing, nor the multi-user X window system for the powerful gift it is.

Those of us who do understand those things are not going anywhere! Why? Because we simply don't have to, and that's a fact often ignored when the failed comparison between Linux and proprietary software desktop solutions is invoked.

Think that one through kids. Think it through really hard, and maybe you may come to see how the open software dynamics work, and through that, why a pronouncement that the Linux Desktop is dead ends being as silly as I make it out to be. We users of that desktop will be perfectly happy to let you know when it's dead, k?

User Journal

Journal Journal: Thanks for the gift subscription! 6

I just received mail notification that a fellow user has bought me a gift subscription to slashdot. I'm already friends/fans with the person but his email address isn't visible so I can't thank the person off-/. (wimp, change your privacy settings and deal with the spam! :P )
 
Not sure what I did to deserve it, but I thank you!
 

User Journal

Journal Journal: Awesome... 4

Short Flash vid...
http://en.tackfilm.se/?id=1273610622233RA56

User Journal

Journal Journal: iPad pre-orders in Canada enabled, I drink the KoolAid 4

Canadian pre-orders started today.

64 GB WiFi version ordered, should be here by May 28. No need for the 3G version, I can tether with MyWi on the iPhone.

My dad picked up the similar model on a trip to the US last week. Was playing with it on the weekend, awesome device. Perhaps not magical but still most impressive.

User Journal

Journal Journal: tangoGPS - alternative to Google Maps Mobile on Linux devices

So back when I had a Blackberry for work, the one app I really got addicted to was Google Maps Mobile. I basically stopped ever planning for travels. I would hop in the car or get off an airplane, think "now what?" and whip out the device and within a minute or two have directions to some place I've never been to before or a list of the nearest restaurants with a smattering of reviews.

Unfortunately, gmm only supports a handful of devices, most of which I'm not interested in. It won't install on my lousy Samsung t629 phone (which I hate, but Opera Mini helps me tolerate). I have a really old version of gmm on my Palm TX which works great, but doesn't support GPS. I almost bought a Nokia N900 to replace my various gadgets, but then I accidentally my old car and had to buy a new one, so took myself out of the preorder queue.

Which lead to my long protracted search for some kind of mobile mapping software for our eeePC 901 running eeebuntu. GPSdrive looked promising, but I couldn't quite get it to work with my iBT bluetooth GPS, or to even scroll out of Germany for that matter. Google Earth sort of worked, but the fonts and Z-buffer were wonky, and my previous experience hooking Google Earth Plus to a GPS wasn't actually all that stellar. I even tried running the Android SDK so I could try installing GMM in the emulator, and also installed androidx86, but alas, gmm wasn't an option in their stripped-down app repositories.

Finally after many google searches, I found tangogps while simply mucking around in aptitude. I was very impressed with both the simplicity of the user interface and the power of all of the features... In addition to supporting several different map sets out of the box (including an "for testing only" google satellite maps scraper), it also has a friend-finder database similar to Google Latitude, and better yet some of the trip meter features I missed from Garmin devices. Plus the inclusion of sources such as the opencyclemap db makes it more useful to me than GMM was. It's also possible to download tiles over a region in advance for offline viewing.

I now have my eeePC linked via bluetooth to both the iBT GPS and my Samsung t629 phone to download tiles from T-mobile's network using my $10/mo. web2go plan. Unfortunately, it doesn't support search yet, but does have rudimentary routing and directions. But it does give me just what I've really wanted -- an overhead moving map display.

Someday I hope Google will make GMM available for "real" computing devices, maybe on ChromeOS or Androidx86 or better yet just as a standard java app (yes, I also looked into installing the Sun Java micro development environment and generic phone emulator, but it looked like a real mess to get things installed and then somehow connected to a real GPS). Or at least porting to the Maemo platform so it would run on the N900 and friends. But barring that, I think I can make do with tangoGPS until I maybe succumb to one of the newer Android 2 devices due out this year.

User Journal

Journal Journal: Palm T5 - TX touchscreen transplant

I don't know why I hadn't thought of this sooner. My Palm TX had a pretty broken touchscreen, with large unresponsive areas in the middle of the screen and in the graffiti area. I had been coping with this for years... writing really small and frustrated graffiti in the corners, and creatively using various combinations of presses around the edges to activate buttons in the middle with touchscreen averaging.

But after replacing the broken screen in my wife's eeePC a few weeks ago (it was only $50 for a beautiful new glossy screen) I thought I might try buying a replacement Palm touchscreen (which go for about $20-$30 and include the special * screwdriver). Then I remembered that I had my old broken Palm T5 lying around, which still had a nice working touchscreen. I don't know why I assumed they wouldn't be compatible earlier...

Anyway, the small bit on my leatherman fits the Palm T* screws fine, and after a bit of drunken internal surgery, the transplant was complete. My Palm TX has a new lease on life, with a nicely calibrated touchscreen and hard buttons on the front that work consistently now.

Of course, now I have to invest in some better protective gear to keep it that way... my jacket pocket just contributes too much lint.

Unfortunately, the power button still doesn't work, but there are apps to compensate for that, like PowerBtn or OffStroke.

User Journal

Journal Journal: Mirrored RAID read performance, where art thou?

Back before mdadm (in the days of mkraid), the Linux RAID1 driver used to give you a performance boost when reading from a mirrored array. Essentially, from 2 mirrored disks, it would read half the data from each disk and give you the whole thing almost twice as fast. At some point, they decided to change that behavior so reads would only be performed from one drive at a time. There was still some small performance boost... it would decrease average seek latency a bit by reading from the hard disk spindle that was physically closer to the sector to be read. And maybe it allowed concurrent reads, so one process could read a file from one disk while another process read a file from the secondary disk... but for some reason, that doesn't seem to increase your overall throughput by anywhere close to a factor of 2... more like 1.3 from my brief testing (and I suspect most of that gain was probably due to disk cache rather than parallel reads).

But after reading a few different Linux RAID sites today, it looks like that you can get that kind of performance boost again out of mirrored arrays by using RAID10,f2 ( --profile far=2 )! And even though it's called RAID10, it even works on arrays as small at 2 disks. It basically works by striping your data across the first half of your drives, and then striping the mirror of that data across the second half. This appears to decrease write performance by about 5% compared to RAID1 or RAID10 near=2 (the default), but the read performance finally increases again not only due to striping, but also because your disk heads now stay near the faster outer rings of your disk drives, and only has to dive down to the inner rings for mirroring writes.

So I'm pretty excited about this since I've kinda been annoyed by it for the past few year. Except that of course I now have to rebuild all my RAID1 and RAID10 arrays to use the far=2 profile :P

Here are links to some of the more useful sites with data:
http://linux-raid.osdl.org/index.php/Performance
http://blog.jamponi.net/2007/12/some-raid10-performance-numbers.html
http://home.comcast.net/~jpiszcz/raid/20080528/raid-levels.html

User Journal

Journal Journal: Just testing out some journal submission changes 8

I don't actually have anything to say. Kathleen is due any day, and I'm looking forward to a few weeks of staying home, getting poor sleep, and changing diapers.
But mostly I'm testing to see if journal saving works properly.

User Journal

Journal Journal: Updates to Journal System 13

We've made some significant updates to the submission/journal system. Visiting Submissions and Journals yields a new form that allows stuff like tags to the data types. There are a number of annoying bugs, but for the most part the dust is starting to settle. More notes will be coming, but this journal entry is really just me putting the final test on the new Journal form.

Government

Journal Journal: Discuss: Cybersecurity Sysadmin Guild

The NYTimes story linked below sparked some thought I wanted hear more from /. about. This is not your typical advocacy post, but for the simple request that we just talk about this stuff. Can that still happen on /. I'm hoping so. Take the info below, read it, then think about it, then contribute what you think will have the most value. The idea is for us to just do a bit of talking for the sake of just learning and thinking for a change.

These kinds of topics are of great interest to me, largely because the ethics and law surrounding them are new and often being formed right now, in our time. That's kind of cool really. It's interesting to consider what we sort out now will define things for generations to come.

In short, we live in interesting times.

http://www.nytimes.com/2009/06/13/us/politics/13cyber.html?_r=1&partner=rss&emc=rss

My intent with this is to just have some good discussion. I've got my flame suit on, and really just am interested on where this takes people. Consider it food for some interesting talk, not so much an advocacy piece. I am wanting to hear some thoughts on this subject matter, whatever they may be. Let's go!

The problem with cyber-defense and our traditional notions of privacy, search, seizure, etc... comes from the virtual nature of Internet communications, geographical portability, and relative inability for many to quantify how the net works in terms we agree on. Simple discussions like "theft" of movies require people understand very subtle things, like infringement and why it's not simple theft. Please, this thread is not about that topic. I contributed it to highlight one of many things we remain very confused as a nation on, not to make a position statement on what happens on a download ok?

Enter the Systems Administrator.

These people did it first. We have a net to wage war in, because they did the work to build something that would actually behave as a virtual space. And there are some fascinating parallels with our history I want to share, then make a statement at the end of this I didn't think I would make. Ideally, that's where some discussion will happen.

Our founders were these very progressive and visionary people. When they formed this nation there were only a few democracies in operation at the time. They were seen as everything from radical to just. We live in that nation today because they structured things to behave as a space where people were free to be people.

The systems administrators who built the net were like them in many ways! They were visionary, progressive and very focused on structure and freedom, knowing that good things would happen without having to actually state them.

As time passes, current generations lose some of the connection to those early builders. Today, both our founders and systems admins are not seen in the same way they were when alive and building.

Our early legislators were mentored in from the builders. Many implied things were honored because they were just, law had not yet been written and ethics controlled how a lot of things got done. Admins are the same way.

I, for example, was mentored my people who I would characterize as first and second generation admins. The net was an open place a lot like early America was. Few people had locks, few people then had cyber security.

The third generation is operating now, with the fourth upon us soon.

When I got introduced to being an admin, ethics were a part of the discussion. Then came the gentlemen's agreements and such. The net was still being formed. Now it's built and being improved, renovated, etc...

Early on, it was not possible to be an admin, without having gone through the passing of the torch. Then it became possible to just become an admin through the course of simple work, and the ratio of those being mentored by those that formed the roots of the thing to those who just end up doing it leans toward no mentoring with each passing day.

Problems escalated as more and more ordinary people jumped into the space and started doing their thing.

The net closed, security was required and the rest brings us to today.

Here's an example of the kinds of things I experienced when the keys to the kingdom were handed to me:

Ethics on privacy. It was obvious that I could examine any portion of our company net. So then, what's the right behavior? Do I read the e-mails, poke at the financials, log browser traffic? The answer is complicated and much of it depends on what the information is for, whether or not a person can be trusted to do the right thing with it, and so on.

I got the title of admin, because the prior one basically told the users I was ready, could be trusted, and had the skill needed to carry them forward. This still happens, and it happens a lot and that is good. When it doesn't happen, there are issues. Or worse, the admin is forced to disregard their ethics to hold a job, and users are left with the results.

My point is this: I don't think it's possible to operate a safe net, without some people getting to know stuff. Our open net requires us to have administrators and that's just how it is. Somebody somewhere has the keys to whatever fiefdom you care to inhabit, and you get to travel in cyberspace simply at their pleasure. They allow that traffic to exist, and they allow it because it is better with that freedom than without.

Witness nations like China and Australia and others who regulate that travel sharply, and with that comes an idea of just how much implied trust we operate on. It's a lot people. An awful lot.

As an admin, I operated (and still do operate) mail servers. Marriages can be broken with the info sitting on that server. Prison terms can be there too. There is a lot of power in that machine, and the admin could use it for personal gain quite easily. There's the implied trust bit right there.

My users know I don't read e-mail. My standard line is that it would simply piss me off, and who wants to do that? The reality is that I know that server needs to be treated in a special way so that the people who inhabit it (and that's an odd way to put it, but it makes sense to me) can just be who they are and do what they do, much like they do getting into a car and driving down the road.

Over the years, I've been asked to cross boundaries. Copy software, crack software, open up the server and take a peek "for the company", and any number of other things. I've said "no" a lot, and have been fortunate enough to be in positions where that "no", and the "why" behind it was heard and respected. I've been forced a time or two and considered an attorney, because the law actually forbid what was being requested. There are many who need their job and or don't care and will just do it. Think about that dynamic too.

So then, Obama wants to essentially create the systems admin for the nation.

IMHO, this is good.

I see everybody worried about trust. The nation is going through the same thing little pools of people went through when the net was forming. A discussion happens:

[admin]

We have networked the computers!

[users]

YEAH!!

But, what about... and it comes! Can others see my stuff, can I see their stuff, will people know things?

[admin --if they are a good one]

Admin lays down the law, ethics and commits to earn the trust of people.

So then, this discussion results in everybody operating under some common assumptions and the admin just compartmentalizes a lot of things and basically sits there and makes it all go in a way that people can live with.

We, as a nation are there now.

We as a community here on /. have been there for a while, with our admins here structuring things so that we can do what we feel compelled to do with few to no inhibitions and a lot of trust. Think about that in the context of this national development about to happen. Interesting no?

I think so.

My proposal is essentially a guild. Cybersecurity is going to require admins and our liberties are going to fall under their privy, or we operate in a less than secure environment and take the risk. That is the national question, but for the guild part. That's mine, at the moment.

If we go the guild route, then we return to how the net was formed and the trust and ethics issues that formed the place and that means people vetting people for the sake of other people.

Will the President actually have his admin tell him "no" and "why", or will that admin just take a peek?

I think about the wiretapping that happened. What if that guild were in place, and they said NO? Or, perhaps they said "maybe", and it went to the courts?

If we have a national systemsadmin, czar, etc... what do you think that looks like, and what power should it have?

Flame, rant, rave, you name it! Let's just talk about this and see where it leads!

User Journal

Journal Journal: Disable ADs?

Hello everyone!

Logged into /. this morning and saw this nice note:

As our way of saying thank you for your positive contributions to Slashdot, you are eligible to disable advertising. Or something like that.

I checked the box to satisfy simple curious interest and got:

Thanks again for helping make Slashdot great!

Thanks guys!

I think I'll probably turn the ADS back on soon though. They don't bother me, and every little bit of revenue counts for most people these days. I do however appreciate being noticed. Some part of me is hoping it's never having anything but EXCELLENT KARMA. Maybe it's a low UID, maybe some other ratio of good comments to bad, or something.

Whatever it is, thanks again!

I'm thinking back on the early years, when Rob was going to school, running /. on old Alpha servers and the smaller community we had then. Man, there are so many people now! Despite this, I scroll through the comments and recognize people. Some are old names, some new, all made an impression on me in some small way, which is why I remember them.

We've come so far. There are times when I log in and feel OLD. Usually, that's on the politics or Internet focused discussions. There is a thing I wanted to journal here about that. I will actually, but first I'll tee it up and also state that I've posted it somewhere else too. Nobody cared! That worries me actually.

There are first generation netizens, and they were the builders. Second Generation netizens would remember the ETERNAL DECEMBER, among other things. Some thirds might do so as well.

I'm a late second, Gen X netizen. Kids jumping on today are probably fourth generation and so many of them have NO clue. Well, that's not right. Many of them do, but the culture of being mentored onto the net has gone. It left with the masses that followed the time when I logged on for the first time.

That was 91. HOLY SHIT! Time passes...

So, to tee up the contribution I have in mind: Obama wants to make a CyberSecurity Czar. Fine. I actually think that's probably a good idea. But, it triggered some musings that I thought I would share for discussion. I'll try the make a journal entry a story deal, put on my flame suit, and see what people think!

User Journal

Journal Journal: SwiftWeasel 1

I am liking Swiftweasel, it is noticeably faster than Iceweasel / Firefox on Linux, especially on netbooks like my eeepc 901 running eeebuntu.

Unfortunately, the deb repository for it is somewhat old (v3.0.3), and current .tgz builds from sourceforge are somewhat old as well (v3.0.5 for x86, and v3.0.6 for x86-64, whereas the current iceweasel / firefox is at v3.0.7). I kinda wish SticKK of the SwiftWeasel Project would post more instructions on how to build swiftweasel from current iceweasel sources.

Until then, I've seen that "about:buildconfig" can be used to identify the compiler and options used. When I get a chance, I'd like to try grabbing the iceweasel deb-src and modifying the build options to match. Don't see anything in there about how to enable Profile Guided Optimization (PGO) which is necessary to make *nix builds of firefox javascript run as fast as Windows builds, as mentioned at this firefox benchmarking site.

Oddly enough, I ran the SunSpider javascript benchmarking suite under both Swiftweasel and Iceweasel, and Swiftweasel actually took a tad longer. I feels much snappier in day-to-day use though, probably because of some of the FasterFox extension options. The default vanilla Iceweasel on the eeepc typically pauses for a second or two on new page loads.

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