I recently purchased the hardware for a new server, I'll get into the details of that in a later post, however I did want to quickly mention a problem I had.

I tried to burn in my S5512WGM2NR motherboard, a Sandy Bridge motherboard from Tyan. It has the the C204 chipset paired with a Xeon E3-1230 and for memory a respectable (at time of writing) 16 GB of ram (4 x KVR1333D3E9S/4G 1333MHz DDR3 ECC CL9 UDIMM).

Anyhow, the MemTest from Fedora 15 locked up instantly and the official MemTest from http://www.memtest86.com/ locked up within 60 seconds or whenever you hit a key. I'm now using MemTest86+ from http://www.memtest.org/ and it works great.

tl;dr

Use MemTest86+ from .org not MemTest86 from .com.

note to self

This ram is weird, unbuffered ecc (udimm) is not common

If you want to randomly change the wallpaper on mac osx you can use the built-in functionality. However, if you want to pick an image from a subdirectory you need to use this little script.

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Continuing from maze solver update, I came across another very large maze at Purpy Pupple wikipedia page. And when I say large, I mean 4000x4000 large. Purpy calls it 2000x2000 but since it is very clearly 4000 pixels by 4000 pixels I'm calling it as 4k.

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The Sandy Bridge reviews sure paint a nice picture for this new cpu. I'm currently leaning towards the i5-2400 or the i7-2600 if I'm feeling rich. The K series are unacceptable since they don't support VT-d.

However, unless the platform can do the following I won't be buying it.

I want to use a discreet video card and the on-chip video card simultaneously. I want to run my htpc in a virtual machine and “give” either of the cards to it via pci passthrough. By having the htpc own the card it should have great performance and if I break X on either the host or the htpc guest I just have to flip the input on my receiver and continue on my way.

Since I currently use kvm and not xen, kvm will need to be upgraded to support display pci passthrough. The guest will need to be full screen of course, Spice may be required.

So hopefully Fedora 15 will be able to handle all that.

Here's a follow up to my previous post, maze solver. I've finally gotten around to solving this properly with a breadth-first search. Shortest path is 16031, 11% better than my previous best.

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If you'd like to be able to easily see which one of your kvm guests is the cpu hog, make links from to qemu-kvm

cd /usr/local/bin
ln -s /usr/bin/qemu-kvm vm_magneto
virsh edit magneto
# change emulator to
<emulator>/usr/local/bin/vm_magneto</emulator>
virsh reload
virsh shutdown magneto
virsh start magneto

I currently use a modded xbox running XBMC (xbox media center) and although I've loved it for many years it is starting to show its age. Its 10 year old cpu just can't decode an h264 encoded movie, plus I'd really like to be able to surf from the couch and view TED Talks and YouTube videos.

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A static variable in a class method are shared between all instances of that class and not per class instance.

#include <stdio.h>

class Foo {
public:

    int foo() {
        static int i = 0;
        i++;
        return i;
    }
};

int main() {

    Foo a, b;

    printf( "a: %d\n", a.foo() );
    printf( "b: %d\n", b.foo() );
}

a: 1
b: 2

EventSync from fbevents.net is a great app to sync OSX iCal with Facebook. However, if you ever do something to your calendar and EventSync is no longer updating your calendar then do the following from a terminal.

rm -r "~/Library/Application Support/SyncServices/Local/clientdata/com.llsoftware.fbevents"

I still don't know what eigenvalues are, what they're for, or how to use them, but I needed to calculate them for work and make sure they were positive.

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