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Linux 3.1 Released With Support for the OpenRISC CPU

dcowart Re:Wiimote support built-in (165 comments)

From the Changelog linked to in the article...

1.3. Filesystem barriers enabled by default in Ext3
Hard disks have a memory buffer were they temporally store the instructions and data issued from the OS while the disk processes it. The internal software of modern disks changes the order of the instructions to improve performance, which means that instructions may or may not be committed to the disk in the same order the OS issued them. This breaks many of the assumptions that filesystems need to reliably implement things like journaling or COW, so disks provide a "cache flush" instruction that the OS uses when it needs it. In the Linux world, when a filesystem issues that instruction, it is called a "barrier". Filesystems such as XFS, Btrfs and Ext4 already use and enable barriers by default; Ext3 supports them but until this release it did not enable them by default: while the data safety guarantees are higher, their performance impact in Ext3 is noticeable in many common workloads, and it considered that it was an unnaceptable performance regression to enable them by default. However, Linux distros like Red Hat have enabled barriers by default in Ext3 for a long time, and now the default for mainline has been changed aswell.

In other words: if you use Ext3 and you note performance regressions with this release, try disabling barriers ("barriers=0" mount option).

about 2 years ago

Linus Torvalds Ditches GNOME 3 For Xfce

dcowart Re:Change for the sake of change? (835 comments)

The ip command is slowly replacing the functionality of the ifconfig command for networking. I recommend it instead.

more than 3 years ago

The Most Useless Key On My Keyboard Is...

dcowart Re:Scroll lock! (939 comments)

It used to be that when you 'scroll lock' a linux console it would hang the machine. The kernel buffers would fill with messages to be dumped to the console and eventually would run out of memory and the machine would hang. Toggle the scroll lock off and it would unlock, dump tons of messages to the console, and things would start running again.

This was especially problematic on KVM's that used the scroll lock key to switch between machines. It would be a week or too and then a server would just stop responding. Ugh.

more than 4 years ago

Using WiMAX To Replace a Phone?

dcowart Re:iPod Touch (169 comments)

Yes, you can actually. I got the apple earphones(needed to replace old ones) & mic set from my local mac store and I hooked them up to an ipod touch with the skype app and was able to make calls easily. This was using only 802.11b/g connections that were open where ever I was located. The biggest problem was spotty wifi connectivity and coverage. Also since I ride a motorcycle I was more worried about having access to emergency services, so I didn't go with it as a solution to totally replace my cellphone.

I could see that if it were economical, you could have all calls go to skype & skype-voicemail and talk when you're close to a wifi connection. While also having a prepaid cell phone for emergency calls. I was very close to doing this but since I'm on a family plan and my cell phone is only $10 extra it wouldn't really save me anything to go that route.


more than 5 years ago

Why IT Won't Power Down PCs

dcowart Re:harder than it seemed (576 comments)

We have deep freeze as well here where I work. We have it turn off the pc's at 11pm. It turns them all on at 2:55am unfrozen, windows update runs at 3am (with the auto-install) also symantec anti-virus runs, and at 4am it refreezes the machines and shuts them back down. Wake-on-Lan will need to be setup on the PC's but this system works very well for patching & updating the machines while also keeping them frozen from mal-ware.

Let your IT guys know, it should be that simple... at least as far as freezing & updates.

more than 5 years ago

Star Trek Premiere Gets Standing Ovation, Surprise Showing In Austin

dcowart Re:I would have rather seen Wrath of Khan (437 comments)

I might have to turn in my slashdot id for this but, I have never seen Wrath of Kahn in any form... just never got around to it.

And I'm totally jealous of those that got to see the new movie!

more than 5 years ago

Rackable Buying SGI Assets For $25M?

dcowart Re:Surprised? (159 comments)

yeah I was ignoring their printing business and just thinking of their unixes... I had forgotten about the Itanics though... like most of the world !zing!

more than 5 years ago

Rackable Buying SGI Assets For $25M?

dcowart Re:Surprised? (159 comments)

Sun not so much, rumors are that IBM may buy them... HP is only alive b/c people are still using HP/UX and Tru64 for things.

IBM learned long ago the money is in selling support contracts. None of the other vendors ever seemed to really grasp that idea.

more than 5 years ago

"Slacker DBs" vs. Old-Guard DBs

dcowart Re:I've never understood the UNIX world's fascinat (267 comments)

In Re: to my Re:, I like sqlite for simple DB applications, I get DB functionality with a very low overhead. Otherwise I use postgresql.

I have used Oracle and some others before now, but those are my two current DB's (sql-engines?) of choice.

more than 4 years ago

"Slacker DBs" vs. Old-Guard DBs

dcowart Re:I've never understood the UNIX world's fascinat (267 comments)

How does it work for searching though? If I just have my "freespace" file and my pointers to records, does a search for some piece of user requested data have to hit every record or is there a hash somewhere for the data contained in the record? You don't mention it in your description.

It seems that the biggest advantage to a relational DB is that the syntax for accessing it is well known, SQL. It has a human read-able interface and while sometimes whonky to work with for complex operations, it provides the simplest cross-platform way to access data. I don't need to know which data blocks hold the data, I just ask the database for them "SELECT slashdotid, name FROM users where slashdotid 20000"... and I get rows of data.

Could I just read it from a file? Yes. Would it be simpler? Maybe. But what if I have 200001 records, then I have to do some magic sorting in my program, and I have to manage memory for them, and disk space, etc. It is simpler to let the DB handle that mess and I just ask for the data I need.

It breaks up the process of programming into data storage and data manipulation/presentation. DB's for storage, my bad python for manipulation and presentation.


more than 4 years ago

Streaming the Inauguration In a School?

dcowart Re:Just do what you did... (201 comments)

First Black President, that's why this is important. I plan to watch it. This is how far we as a nation have come in the 60 years since the civil rights movement and the Jim Crow laws that held black people down for so long. More than just another president being inaugurated this is a statement that anyone can achieve anything they push for. Yes, I'm a flag waving optimist about this but having grown up in an inner city and having seen the devastation of being poor in America, It makes me hopeful that things can change for the better.

This is the kind of thing that can give an inner city kid a shred of hope that he can get out of the slums and into something better.

I'm starting to get all preachy now, but that's why this is something kids should watch.

more than 5 years ago

Age of Conan Servers To Merge, Funcom Sees Layoffs

dcowart Re:I did predict the suckage. (109 comments)

I'm going to second that. Wrath is very nicely done. The graphics are visually arresting. The quests aren't just kill six snow moose, it's go kill 10 crazed dwarfs and crack open their skulls to see if their brains are rotten... and I'm all for the skull cracking.

Blizz learned a lot from the BC expansion and definitely made this one better. I am a fan of WoW and have been playing for three years now. I often take breaks from it to play steam games, but no other MMO has offered anything remotely like it in terms of ease of use, that is, it doesn't act like it hates the player. But this is an AoC article so I'll stop being a slavering fan-boy now.

more than 5 years ago

Of childhood "building" toys, my favorite is ...

dcowart Re:The best (785 comments)

The stone blocks are "Richter's Anchor Stone Building Sets". I liked your photos of them and did a little googling to find them. has a lot of info about them and some pictures. I also found them at some other toy retailers (google is my friend).

Makes me wish I had some when I was a kid or that I had kids to give them too now.

more than 5 years ago



Dennis Ritchie, kill -9

dcowart dcowart writes  |  more than 2 years ago

dcowart writes ""Computer scientist Dennis Ritchie is reported to have died at his home this past weekend, after a long battle against an unspecified illness. No further details are available at the time of this blog post.""
Link to Original Source

dcowart dcowart writes  |  more than 7 years ago

dcowart writes ""John W. Backus, who assembled and led the I.B.M. team that created Fortran, the first widely used programming language, which helped open the door to modern computing, died on Saturday at his home in Ashland, Ore. He was 82." Source: NY Times. I first read this on the Beowulf mailing list, where a lively discussion of programming in Fortran vs. C vs. C++ was in process..."



A086865 solution in python

dcowart dcowart writes  |  more than 6 years ago

OEIS A086865 in python

import math

def isprime(possprime):
        """returns t/f if number is prime or not"""
        for x in range(2, int(possprime/2)+1):
                if possprime % x == 0:
                        return False
                return True

n = 0

while n < 10:
        pp = 2 * math.pow(10,n) + 11
        print "Working on ", n
        if isprime(pp):
                print n, " gives ", pp, " which is prime."

Works for python up to n = 8. Then runs out of memory :-( Just means I have to rewrite it in C.


Data is Heavy...

dcowart dcowart writes  |  more than 6 years ago

So I've been neglecting my slashdot journal for too long.

I am moving hosting providers to save some money. Virtual data is hard to move. Sure, file copies happen fast, but directories, databases, emails all these things take work to move. Data has no mass, so why is it difficult to move? Well, it is energy so it can in theory have mass...

So moving masses of data, I spend my afternoons entwined in it.



dcowart dcowart writes  |  more than 8 years ago

I created an account on the iFolder wiki to delete some casino spam on one of their developer pages. Bastards. The technology looks good though. I'm wondering how to incorporate it into some of the things we do at my current workplace...


Opensuse on Sparc

dcowart dcowart writes  |  more than 8 years ago

I got my Sun blade 100 in and am working on getting OpenSuSE 10 ported to it. I had to install gentoo on it first. Emerge somethings, rpm, bzip2, etc... I pulled all the rpmbuild macro files from an i586 opensuse box and replaced the /usr/lib/rpm installed macros (from redhat). That gives me something like a suse rpm build environment. I then had to fix up the /usr/lib/rpm/sparc64-linux/macros file to include some things suse sticks in the other arches and remove the redhat/gentoo things. I also had to remove the -m64 flag to the gcc opts b/c it conflicts with long_double_64 for some reason.

This has been a week long project and it's starting to actually build packages well now. The first steps were just in getting things working.


So much for writing more often...

dcowart dcowart writes  |  more than 8 years ago

LOL, Well I wanted to write more this week, but never did. Oh Well!

Anyway, the sun blade 100 came in like I wanted and due to my own oversight, I didn't have any ECC PC133 RAM to put in it. That sucked. So I'm getting some more on ebay and hope to have it in in the next week. Then I'll be able to get cranking with the linux. I'm resisting the urge to buy another sun blade though. I'm thinking compiler farm for linux builds. Maybe a little later on. I did get to setup the serial console from it to my linux box (using minicom, reminds me of using Telix (tellix?) in the old days). That was interesting and kinda fun. Right now it's sitting on top of my Athlon-64 linux box with a serial cable draped down the side of it going to the port on the back of the linux box... and both machines have their cases removed.

I have one friend who says that I should only install solaris on it. That it would be a waste to install linux. I choose not to listen to him. The vision is to setup linux b/c I think it would be cool. There are tons of these things floating around. I think something interesting can be done with them.

Once I had pretty well worked the sun blade to death, I put together one of my orgnial lunch box machines, a Shuttle SV25 system. The fan on the power supply is going though so I've got to replace it, which means either getting a new system or cracking the power supply... not sure about either solution.. I may try disconnecting the internal one and then putting a new one outside the power supply... we'll see though.


It's been an ebay weekend.

dcowart dcowart writes  |  more than 8 years ago It's been an ebay weekend. I'm getting a Sun Blade 100 workstation and a removable hard drive caddy. I've got bids in on another hard drive caddy and a 5-bay IDE hard drive cage for ATA drives. Once I combine that with a 3ware 7500 series RAID controlled I'll be in business!! W00t! I'm sticking with ATA b/c I already have a few of the same size drives to use with it. So I've been having fun spending money on ebay.

I spent some time Sunday working on my computers. I've been trying to get working on one of my PC's that has been giving me problems and I think now that the PC is finally giving up it's ghost. The sequence that normally causes the cdrom to eject now causes the machine to reboot. I've been having problems with the USB ports on it as well and the PS/2 ports have been dead for a while. So I'm assuming that there is some issue with the Northbridge (which controls those things) and so I'm dumping the motherboard :-(

I'm gaining a new one though in the form of a Sun Blade 100 though so that makes me happy. I'm going to try to port opensuse to it. LOL that should keep me off the streets for a while. I'm going to setup my workstation to serve the sources for the suse packages so I can host them out via NFS to it and use it to recompile and test, but leaving the data on the the network.

We'll see how it goes. I'm going to try to keep my journal here updated more often too. I just need to get into the habit more often.


New 2001FP waiting for me and things to do...

dcowart dcowart writes  |  more than 8 years ago When I got home I had a great surprise waiting for me. My new Dell 2001FP was waiting for my by the door. So now I have a 20" LCD monitor hooked up to my linux boxes. It's very nice and I'm typing this now on my KDE Desktop with Firefox open. It makes me very happy! :-)

In my own computer work, I've taken my primes machine and turned it into a media center in my living room. So I've gotta get it up again, I need new hardware to use my other box is just dying (I think part of the Northbridge is broken, various built-in things on the motherboard have died), luckily I can still use the PC itself. is my usual shopping destination. I've gotta get back to work on the KJV translation. My Dream Library site is up, but not getting much traffic.


Dead DB server and OpenSUSE wtihout PostgreSQL???

dcowart dcowart writes  |  more than 8 years ago

Lost my home database server last night. It had been up and running for a while and I wanted to update it from FC1 to OpenSUSE 10. I've been using OpenSUSE at work for a while and really enjoying it. It seems to be a very viable desktop linux candidate. So I backed up the important data and configs and rebooted with the OpenSuSE cd in. So it took forever to boot, I'm talking like five minutes or more. It finally got to the first setup screen and I tried to use a mouse... It wasn't working so I tried by-passing my KVM switch, still dead, I tried a second mouse nothing, finally I tried a USB mouse, Success!!! I was really happy about this stupid mouse. (I also seem to have lost a small Playstation Mouse in the process. That I'm really not happy about. :-( ) I got through the next few screens clicking away and that I was trying to type in the volume group name in the LVM setup and the keyboard wasn't working, tried the same steps and darn it I had to use a USB keyboard to do things. If that means what I think it does, the PS/2 parts of the Northbridge of the are blow/corrupted. I chugged along with the USB devices, and began the actual copying files part of the install. Once it got to where it would normally ask for CD 2 it rebooted. {sigh} That blows. It now hangs while trying to boot.

So I've begun my search for another web/database server for my house. I am going cheap b/c it's not a highly loaded machine. I'm looking at a sempron 64 mobo that should do nicely, that sempron 64 2800 and a gig of RAM should not cost more that $150 or so. ( pricing) I'm just gonna have to wait until I get paid again :-(

During the install of OpenSuSE from the CD's I noticed something though. While they do include the PostgreSQL libraries for connecting to a Postgres DB, they don't actually include the Database itself. This maybe a CD vs. DVD thing. Novell is doing something funky where the packages don't match between the OSS version and the "Non-Free" version. Although they do include some OSS software in the Non-Free version. I'm wondering if it's not included b/c it's an "enterprise" DB. I'm gonna compare it with the SLES 9 version and see what's different. Hopefully I can update the OpenSUSE Wiki with the info sometime today.


LVM in linux...

dcowart dcowart writes  |  more than 8 years ago

If you aren't using LVM in linux by now, run to the howto, read it, and start using it on all your servers. IT ROCKS!! I needed more space for my /var partition so I lvextend'ed the partition using the free PV's in my VG and then resize2fs'ed the ext3 fs to use the new space. It's just great to be able to do these operation without having to take the box down. It's much much more flexible that having hard coded partitions. ReiserFS makes it easier b/c then I don't have to unmount the partition to grow it larger. I think XFS is the same way. Although to shrink it, the partition must be unmounted.

LVM is a good thing all around.


Captain Keys is a pain in the butt still...

dcowart dcowart writes  |  more than 8 years ago

I've gone back to playing Halo for a while on the harder setting. I forgot how much I disliked Captain Keys. The jerk keeps getting captured or crashing space ships and so a lot of the game is driven by rescuing him. It's a great game though. It probably has the best story behind the game of any I've ever played. It brings back good memories of playing with Bill, one of my old roommates, and seeing the guilty spark (a game character) saying, "I've got a bad feeling about this". You can't shoot the guilty spark no matter how hard you try. And while he's not evil, he is doing his job trying to destroy the solar system. Flood are still just as creepy and I still curse like a maniac as they come jumping out from everywhere. There still is an element of fear b/c I know they are coming and I know they are going to do a lot of damage before I kill them. It's a game where I'll still jump around when I hear them attacking me.

In other news I've been thinking of trying to start a tech support group for non-profit groups. Something cheaper than the other rip-offs and something more permenant than the-guy-that-knows-something-about-pc's . I don't know if it could take off, but I think it could. I don't know what kind of capital I would need either. It seems like a strange thing to do, but I can see something of a need out there.



Trouble canceling accounts.

dcowart dcowart writes  |  more than 8 years ago

Crap. Trying to cancel various accounts for things online shows me just how much ppl want to keep my business. It's pretty much impossible. WoW gets kudo's for making it very easy and usefull.



I found my hostid....

dcowart dcowart writes  |  more than 8 years ago


Prints a hexidecimal number globally unique to your host.

In linux (and AIX and Tru64) based on the IP address of the host. In Solaris based on the MAC address of the host and stored in the PROM. Solaris doesn't guarantee uniqueness. With NAT'ing Linux can't either anymore...

    SuSE Linux had it as part of the util-linux rpm. Looking at the HISTORY for that package hostid had been removed in 1997. Hmmm... Check the source, best resort of a linux geek, and yes, it's not there. Grab a Redhat SRC rpm for util-linux. It's not there either, but it does at least have a note that it had been moved to sh-utils. AhHA! Jump to sh-utils has been combined into core-utils, grab the source. Yes! It's there... but wait, hostid is pretty much a syscall to gethostid.

gethostid(2) is in unistd.h, rpm -q tells me it is in glibc, grab the glibc source. And I have it, buried five directories down is the source for gethostid. It uses the IP address of the system but splits it into two pieces and then flips each piece; so gets changed to before having each piece changed to hex. reading the source though, if it can't find the IP address of the system, it generates a random number...

This all came up b/c I tried to set my hexidecimal hostid to 0xDEADBEEF. The AIX freshly allocated pointer value. I also notice that while the Linux version of this command outputs hex, it requires decimal to be input on the command line. The AIX and Tru64 versions allow an ip address to be input, a much more friendly way of doing it, espcially since it uses the IP address anyway.

That was my hostid fun for yesterday.


PS. I also re-arranged my computer room some.


Message Passing....

dcowart dcowart writes  |  more than 8 years ago

I've just been having an interesting time with the last few bits of the cluster setup. We are almost done with the system administration part of it though. I've written a small application for testing the cluster and the MPI libraries (Message Passing Interface) behind it.

MPI is a set of libraries that give a standard way for nodes on a cluster to send data between each other. It makes cluster programming a little easier b/c you don't have worry about the details of how they communicate, you can focus on What gets communicated. I wrote a program yesterday to find the factorials of all the numbers between 1 and 200000 this way. It is actually a very bad program in that in that I just had each node do the same thing, not really what you want in a real world situation. I'm working on the next part of that today, having the master node assign each rank a number to work on and then having the node return the number to the master. Still a pretty simple project but the goal is to expand it to do two simple series expansions, 'e' the base of the natural logarithm and 'pi' the ratio of the circumfrance of a cirle to it's radius. Both of those would make decent cluster tests. 'e' directly depends on factorials so the stuff I'm doing now is my base for getting that working. I'm worried about the GMP libries that I also use though, I'm not sure they are safe for using in this kind of work. We'll see though.


not much from yesterday

dcowart dcowart writes  |  more than 11 years ago

after work I took a bunch of pictures from megatokyo, ascii art and other junk and decorated the men's room. fun way to celebrate finally getting exchange & Active directory working in a subdomain of a real unix system.

I posted a bad program to the list. a really bad way to find the data about a message.


found megatokyo today....

dcowart dcowart writes  |  more than 11 years ago I've been reading megatokyo like a maniac for the past few hours. It's really good, I'm having a little trouble distinquishing between some of the characters but that could be because my eyes are watering over...

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