Neotextus

Archive for October, 2005

Copy on write memory for Xen

by on Oct.03, 2005, under Computing

Xen

It looks like the Xen Virtual Machine Monitor is going to get a copy on write memory sub-system sometime soon, removing one of the few remaining performance limitations on the platform. Thanks to the work of researchers at UCSD which will be presented in a paper at this years ACM Symposium on Operating Systems Principles, a copy-on-write memory sub-system has been developed for the Potemkin Virtual Honeyfarm. Whilst the existing implementation is specific to the honeyfarm, future versions should be able to provide a more general solution much like the similar VMware resource management capability. Having the ability to ‘flash clone’ a virtual machine potentially enables some radically new uses for virtual machines above and beyond the honeypot, particularly when combined with a copy on write filesystem like Parallax, such as the ability to “time-travel” by rolling back the state of a virtual machine to that prior to a failure or exploit.

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Jabberd 2

by on Oct.03, 2005, under Computing

I am a big fan of instant messaging, and of XMPP in particular as an open standard. So much so that I run our own Jabberd2 server at work, and we have done a bunch of work on using XMPP services as the basis for wide-scale system management and eventing systems. Having said that, I have always found the open source servers to be a little fragile.

My latest issue was to get into work this morning to find that a routine bug fix for the mysql libraries had broken my jabber installation. Even worse, a quick Google search could only find advice on how to fix the problem using configuration options which had changed, or showed that I was not alone in having this issue :-( So here it is, for those of you running Jabberd2 on Fedora Core 4 (FC4), you need to make sure that you have mysql-devel installed, and then:

./configure --with-extra-include-path=/usr/include/mysql --with-extra-library-path=/usr/lib/mysql
make
make install

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Photo Rally

by on Oct.01, 2005, under Photography

Portland Community College have organised a photo rally (a treasure hunt really) at their Sylvania campus. I decided to take up the challenge today, and here are the results.

Bark Start at the library, just to the left and behind the bus kiosks. Head to the red. While walking, take a close-up picture of the peeling white canoe construction material used by Native Americans in the East and Midwest.
Rockets Shoot all six rockets on the needle.
Teepee Take a picture of the library sign over the small rusty teepee-like sculpture.
Butt Stop While on the same plateau, shoot the Butt Stop.
Playing Cross over to the Little Theatre area. Show whats playing in the middle (with pins).
Refreshing Head towards parking lot, but before getting there … Show something refreshing with lights, on the side of the building.
Serpent [1] Show the inline serpents twice – once all sharp,
Serpent [2] one fading into fuzzy.
Rainbow Take a picture of a rainbow with an apple on top.
Warning [1] Go around the building, and while enroute to your next destination … take two photographs of two different kinds of warning signs, one on your right,
Warning [2] one on the left
Messages Turn left, downhill. Take a picture of a place where dogs love to leave messages.
Stop Photograph the plea for ‘being able to stop quickly’, with the maple tree behind it.
Sleeping Tools Shoot the place where tools sleep, frames with flora and guidance systems.
Pine Cones Silhouette the pine branches and cones, with a celestial backdrop.
Danger Enter at the Do Not Enter. Photograph the Danger Warning on the machine screen while having your lens touch the protective screen (between the verticals), and shooting wide open for shallow depth of field.
Circles Follow the sidewalk and go left up the stairs. Shoot the black circles.
Mercury Proceed up. Take a picture of the name of the only metal which is liquid at ordinary temperatures, without you in it.
Profiles Stay straight and then turn right on the sidewalk, passing the toilets. Turn left at the grove of four. Take one picture showing two profiles and one straight face of the three unmoving subjects.
Mermaid Go to the nearby building. Show where a mermaid might be comfortable, with everything sharp.
Annex Turn right, into the building. Take a picture of the Annex, without the Seattle.
Frappacino Move to the end case. Take a picture of the Frappacino without competition.
Flyer Walk to the notices under cover. Go in for a close look at an information flyer.
Shaft Take a picture where you get the shaft, either side.
Storage Go downstairs. Photograph the secure storage once, with sharp up-close and fuzzy in the distance.
Notches Show 39 notches on a wheel.
Hot and Fast Take a picture of the device where you can get something hot, fast.
Copycat Show the LED instructions on the copycat.
Elevator Go back to the elevator, and while walking, take a light meter reading of the center of the building. Then go into the elevator and travel up to the top. While riding up to the top floor, take a picture out the window showing vertical motion.
Favorite Walk to the light brown display cases. Shoot your favorite without you in it.
Reflections [1] Go down two levels, using the stairs and exit out the doors on the opposite side of where you first entered. Turn left and go down the stairs, turning left again. Go through the white traffic gates. Turn left at the dumpster, following the sidewalk by the building. Take 2 pictures of the pool building area, with and without reflections on the window.
Reflections [2]
Foliage Go upstairs, turn right and go up more stairs. Then turn left. Approaching the stairs, near the entry to the CC, veer diagonally for 60 feet. While stainding in one stop, unmoving, take two pictures of the dedication on the natural monument – one with the foliage in sharp, and the other with the foliage out of focus.
Clock Turn right and go up the stairs into the College Center. Go upstairs again. Take a picture of the glowing mechanical device that governs our schedules.
Eyes Near the FYI counter, take one picture of the vertical robotic eyes without more post than necessary
Spy Be an international spy. Show the communication device top line sharp, but make the bottom line unintelligible.
Juice It Up Go downstairs by the Juice It Up. Make the JUI signage words be visually amicable with the color.
Dining Hall Go down the hall and turn right, approaching the dining hall. Shoot a wide angle of the dining hall.
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