Planet Linux Plumbers Conf

June 03, 2009

Darrick Wong

Picspam!

/me rounded up a bunch of (old) panoramas and put them into the high-definition panorama viewer. Be sure to check out the (huge spike in memory cache when you load the) panorama previewer (click the "See All" button).

June 03, 2009 02:27 AM

August 27, 2008

Stephen Hemminger

Exploring transactional filesystems

In order to implement router style semantics, Vyatta allows setting many different configuration variables and then applying them all at once with a commit command. Currently, this is implemented by a combination of shell magic and unionfs. The problem is that keeping unionfs up to date and fixing the resulting crashes is major pain.

There must be better alternatives, current options include:
  • Replace unionfs with aufs which has less users yelling at it and more developers.
  • Use a filesystem like btrfs which has snapshots. This changes the model and makes api's like "what changed?" hard to implement.
  • Move to a pure userspace model using git. The problem here is that git as currently written is meant for users not transactions.
  • Use combination of copy, bind mount, and rsync.
  • Use a database for configuration. This is easier for general queries but is the most work. Conversion from existing format would be a pain.
Looks like a fun/hard problem. Don't expect any resolution soon.

by Linux Network Plumber (noreply@blogger.com) at August 27, 2008 10:20 PM

April 16, 2017

Paul E. McKenney

Book review: "Fooled by Randomness" and "The Black Swan"

I avoided “The Black Swan” for some years because I was completely unimpressed with the reviews. However, I was sufficiently impressed a recent Nassim Taleb essay to purchase his “Incerto” series. I have read the first two books so far (“Fooled by Randomness” and “The Black Swan”), and highly recommend both of them.

The key point of these two books is that in real life, extremely low-probability events can have extreme effects, and such events are the black swans of the second book's title. This should be well in the realm of common sense: Things like earthquakes, volcanoes, tidal waves, and asteroid strikes should illustrate this point. A follow-on point is that low-probability events are inherently difficult to predict. This also should be non-controversial: The lower the probability, the less the frequency, and thus the less the experience with that event. And of my four examples, we are getting semi-OK at predicting volcanic eruptions (Mt. St. Helens being perhaps the best example of a predicted eruption), not bad at tidal waves (getting this information to those who need it still being a challenge), and hopeless at earthquakes and asteroid strikes.

Taleb then argues that the increasing winner-takes-all nature of our economy increases the frequency and severity of economic black-swan events, in part by rendering normal-distribution-based statistics impotent. If you doubt this point, feel free to review the economic events of the year 2008. He further argues that this process began with the invention of writing, which allowed one person to have an outsized effect on contemporaries and on history. I grant that modern transportation and communication systems can amplify black-swan events in ways that weren't possible in prehistoric times, but would argue that individual prehistoric people had just as much fun with the black swans of the time, including plague, animal attacks, raids by neighboring tribes, changes in the habits of prey, and so on. Nevertheless, I grant Taleb's point that most prehistoric black swans didn't threaten the human race as a whole, at least with the exception of asteroid strikes.

My favorite quote of the book is “As individuals, we should love free markets because operators in them can be as incompetent as they wish.” My favorite question is implied by his surprise that so few people embrace both sexual and economic freedom. Well, ask a stupid question around me and you are likely to get a stupid answer. Here goes: Contraceptives have not been in widespread use for long enough for human natural selection to have taken much account of their existence. Therefore, one should expect the deep subconscious to assume that sexual freedom will produce lots of babies, and that these babies will need care and feeding. Who will pay for this? The usual answer is “everyone” with consequent restrictions on economic freedom. If you don't like this answer, fine, but please consider that it is worth at least what you are paying for it. ;–)

So what does all of this have to do with parallel programming???

As it turns out, quite a lot.

But first, I will also point out my favorite misconception in the book, which is that NP has all that much to do with incomputability. On the other hand, the real surprise is that the trader-philosopher author would say anything at all about them. Furthermore, Taleb would likely point out that in the real world, the distinction between “infeasible to compute” and “impossible to compute” is a distinction without a difference.

The biggest surprise for me personally from these books is that one of the most feared category of bugs, race conditions, are not black-swan bugs, but are instead white-swan bugs. They are quite random, and very amenable to the Gaussian statistical tools that Taleb so rightly denigrates for black-swan situations. You can even do finite amounts of testing and derive good confidence bounds for the reliability of your software—but only with respect to white-swan bugs such as race conditions. So I once again feel lucky to have the privilege of working primarily on race conditions in concurrent code!

What is a black-swan bug? One class of such bugs caused me considerable pain at Sequent in the 1990s. You see, we didn't have many single-CPU systems, and we not infrequently produced software that worked only on systems with at least two CPUs. Arbitrarily large amounts of testing on multi-CPU systems would fail to spot such bugs. And perhaps you have encountered bugs that happened only at specific times in specific states, or as they are sometimes called, “new moon on Tuesdays” bugs.

Taleb talks about using mathematics from fractals to turn some classes of black-swan events into grey-swan events, and something roughly similar can be done with validation. We have an ever-increasing suite of bugs that people have injected in the past, and we can make some statements about how likely someone is to make that same error again. We can then use this experience to guide our testing efforts, as I try to do with the rcutorture test suite. That said, I expect to continue pursuing additional bug-spotting methods, including formal verification. After all, that fact that race conditions are not black swans does not necessarily make them easy, particularly in cases, such as the Linux kernel, where there are billions of users.

In short, ignore the reviews of “Fooled by Randomness” and “The Black Swan”, including this one, and go read the actual books. If you only have time to read one of them, your should of course pick one at random. ;–)

April 16, 2017 09:13 PM

February 26, 2017

Paul E. McKenney

Stupid RCU Tricks: What if I Knew Then What I Know Now?

During my keynote at the 2017 Multicore World, Mark Moir asked what I would have done differently if I knew then what I know now, with the “then” presumably being the beginning of the RCU effort back in the early 1990s. Because I got the feeling that my admittedly glib response did not fully satisfy Mark, I figured I should try again. So imagine that you traveled back in time to the very end of the year 1993, not long after Jack Slingwine and I came up with read-copy lock (now read-copy update, or just RCU), and tried to pass on a few facts about my younger self's future. The conversation might have gone something like this:

You  By the year 2017, RCU will be part of the concurrency curriculum at numerous universities and will be very well-regarded in some circles.
Me  Nice! That must mean that DYNIX/ptx will also be doing well!

You  Well, no. DYNIX/ptx will disappear by 2005, being replaced by the combination of IBM's AIX and another operating system kernel started as a hobby.
Me  AIX??? Surely you mean Solaris, HP-UX or Ultrix! And I wouldn't say that BSD started as a hobby! It was after all fully funded research.

You  No, Sun Microsystems was acquired by Oracle in 2010, and Solaris was already in decline by that time. IBM's AIX was by then the last proprietary UNIX operating system standing. A new open-source kernel called "Linux" became the dominant OS.
Me  IBM??? But they are currently laying off more people each month than Sequent employs worldwide!!! Why would they even still be in business in 2010?

You  True. But their new CEO, Louis Gerstner, will turn IBM around.
Me  Well, yes, he did just become IBM's CEO, but before that he was CEO of RJR Nabisco. That should work about as well as John Sculley's tenure as CEO of Apple. What does Gerstner know about computers, anyway?

You  He apparently knew enough to get IBM back on its feet. In fact, IBM will buy Sequent, so that you will become an IBM employee on April 1, 2000.
Me  April Fools day? Now I know you are joking!!!

You  No joke. You will become an IBM employee on April 1, 2000, seven years to the day after Louis Gerstner became an IBM employee.
Me  OK, I guess that explains why DYNIX/ptx doesn't make it past 2005. That is really annoying! So the teaching of RCU in universities is some sort of pity play, then?

You  No. Dipankar Sarma will get RCU accepted into Linux in 2002.
Me  I could easily believe that—he is very capable. So what do I do instead?

You  You will take over maintainership of RCU in 2005.
Me  Is Dipankar going to be OK?

You  Of course! He will just move on to other projects. It is just that there will be a lot more work needed on RCU, which you will take on.
Me  What more work could there be? It is a pretty simple mechanism, way simpler than a memory allocator, for example.

You  Well, there will be quite a bit of scalability work needed. For example, you will receive a scalability bug report involving a 512-CPU shared-mmeory system.
Me  Hmmm... It took Sequent from 1985 to 1997 to get from 30 to 64 CPUs, so that is doubling every 12 years, so I am guessing that I received this bug report somewhere near the year 2019. So what did I do in the meantime?

You  No, you will receive this bug report in 2004.
Me  512-CPU system in 2004??? Well, suspending disbelief, this must be why I will start maintaining RCU in 2005.

You  No, a quick fix will be supplied by a guy named Manfred Spraul, who writes concurrent Linux-kernel code as a hobby. So you didn't do the scalability work until 2008.
Me  Concurrent Linux-kernel coding as a hobby? That sounds unlikely. But never mind. So what did I do between 2005 and 2008? Surely it didn't take me three years to create a highly scalable RCU implementation!

You  You will work with a large group of people adding real-time capabilities to the Linux kernel. You will create an RCU implementation that allowed readers to be preempted.
Me  That makes absolutely no sense! A context switch is a quiescent state, so preempting an RCU read-side critical section would result in a too-short grace period. That most certainly isn't going to help anything, given that a crashed kernel isn't going to offer much in the way of real-time response!

You  I don't know the details, but you will make it work. And this work will be absolutely necessary for the Linux kernel to achieve 20-microsecod interrupt and scheduling latencies.
Me  Given that this is a general-purpose OS, you obviously meant 20 milliseconds!!! But what could RCU possibly be doing that would contribute significantly to a 20-millisecond interrupt/scheduling delay???

You  No, I really did mean sub-20-microsecond latencies. By 2010 or so, even vanilla non-realtime Linux kernel will easily meet 20-millisecond latencies, assuming the hardware and software is properly configured.
Me  Ah, got it! CPU core clock rates should be somewhere around 50GHz by 2010, which might well make those sorts of latencies achievable.

You  No, power-consumption and heat-dissipation constraints will cap CPU core clock frequencies at about 5GHz in 2003. Most systems will run in the 1-3GHz range even as late as in 2017.
Me  Then I don't see how a general-purpose OS could possibly achieve sub-20-microsecond latencies, even on a single-CPU system, which wouldn't have all that much use for RCU.

You  No, this will be on SMP systemss. In fact, in 2012, you will receive a bug report complaining of excessively long 200-microsecond latencies on a system running 4096 CPUs.
Me  Come on! I believe that Amdahl's Law has something to say about lock contention on such large systems, which would rule out reasonable latencies, let alone 200-microsecond latencies! And there would be horrible reliability problems with that many CPUs! You wouldn't be able to keep the system running long enough to measure the latency!!!

You  Hey, I am just telling you what will happen.
Me  OK, so after I get RCU to handle insane scalability and real-time response, there cannot be anything left to do, right?

You  Actually, wrong. Energy efficiency becomes extremely important, and you will rewrite the energy-efficiency RCU code more than eight times before you get it right.
Me  Eight times??? You must be joking!!! Seems like it would be better to just waste a little energy. After all, computers don't consume all that much energy, especially compared to industrial and transportation systems.

You  No, that would not work. By 2005, there are quite a few datacenters that are limited by electrical power rather than by floor space. So much so that large data centers open in Eastern Oregon, on the sites of the old aluminum smelters. When you have that many servers, even a few percent of energy savings translates to millions of dollars a year, which is well worth spending some development effort on.
Me  That is an insanely large number of servers!!! How many Linux instances are running by that time, anyway?

You  By the mid-2010s, the number of Linux instances is well in excess of one billion, but no one knows the exact number.
Me  One billion??? That is almost one server for every family in the world! No way!!!

You  Well, most of the Linux instances are not servers. There are a lot of household appliances running Linux, to say nothing of battery-powered handl-held smartphones. By 2017, most of the smartphones will have multiple CPUs.
Me  Why on earth would you need multiple CPUs to make a phone call? And how would you fit multiple CPUs into a hand-held device? And where do you put the battery, in a large backpack or something???

You  No, the entire device, batteries, CPUs and all, will fit easily into your shirt pocket. And these smartphones can take pictures, record video, do video conference calls, find precise locations using GPS, translate among multiple languages, and much else besides. They are really full-fledged computers that fit in your pocket.
Me  A pocket-sized supercomputer??? And how would I possibly go about testing RCU code sufficiently for your claimed billion instances???

You  Interesting question. You will give a keynote at the 2017 Multicore World in February 2017 at Wellington, New Zealand describing some of your plans. These plans include the use of formal verification in your regression test suite.
Me  Formal verification of highly concurrent code in a regression test suite??? OK, now I know for sure that you are pulling my leg! It has been an interesting conversation, but I must get back to reality!!!


My 1993 self did not have a very accurate view of 2017, did he? As the old saying goes, predictions are hard, especially about the future! So it is quite wise to take such predictions with a considerable supply of salt.

February 26, 2017 11:09 PM

September 22, 2016

Sri Ramkrishna

Making money from copylefted code

I wanted to put this out there while I still have it fresh in my mind. Here at the copyleft BoF with Bradlely Kuhn at LAS GNOME. One of the biggest take away from this is something that Bryan Lunduke said that people are able to make money off from copyleft if we don’t actually brand it as free and open source software. So it seems that if we don’t advertise something as free or open source or that there is software available, then there is a decent chance that you can make money.

Which goes back to the interesting conversation we had the previous day on pretty much the same topic. Just fascinating stuff.

by sri at September 22, 2016 06:04 PM

September 20, 2016

Sri Ramkrishna

We’re going to partay, karamu, fiesta, forever

GNOME release 3.22 happens to be during one of the core days of the Libre Application Summit Hosted by GNOME (LAS GNOME) On top of a high rise, in Portland Oregon, we’re going to celebrate GNOME 3.22 in grand style with the conference participants and end the core days at LAS GNOME!

by sri at September 20, 2016 12:05 AM

September 06, 2016

Greg KH

4.9 == next LTS kernel

As I briefly mentioned a few weeks ago on my G+ page, the plan is for the 4.9 Linux kernel release to be the next “Long Term Supported” (LTS) kernel.

Last year, at the Linux Kernel Summit, we discussed just how to pick the LTS kernel. Many years ago, we tried to let everyone know ahead of time what the kernel version would be, but that caused a lot of problems as people threw crud in there that really wasn’t ready to be merged, just to make it easier for their “day job”. That was many years ago, and people insist they aren’t going to do this again, so let’s see what happens.

I reserve the right to not pick 4.9 and support it for two years, if it’s a major pain because people abused this notice. If so, I’ll possibly drop back to 4.8, or just wait for 4.10 to be released. I’ll let everyone know by updating the kernel.org releases page when it’s time (many months from now.)

If people have questions about this, email me and I will be glad to discuss it.

September 06, 2016 07:59 AM

April 06, 2009

Darrick Wong

January 15, 2014

Greg KH

kdbus details

Now that linux.conf.au is over, there has been a bunch of information running around about the status of kdbus and the integration of it with systemd. So, here’s a short summary of what’s going on at the moment.

Lennart Poettering gave a talk about kdbus at linux.conf.au. The talk can be viewed here, and the slides are here. Go read the slides and watch the talk, odds are, most of your questions will be answered there already.

For those who don’t want to take the time watching the talk, lwn.net wrote up a great summary of the talk, and that article is here. For those of you without a lwn.net subscription, what are you waiting for? You’ll have to wait two weeks before it comes out from behind the paid section of the website before reading it, sorry.

There will be a systemd hack-fest a few days before FOSDEM, where we should hopefully pound out the remaining rough edges on the codebase and get it ready to be merged. Lennart will also be giving his kdbus talk again at FOSDEM if anyone wants to see it in person.

The kdbus code can be found in two places, both on google code, and on github, depending on where you like to browse things. In a few weeks we’ll probably be creating some patches and submitting it for inclusion in the main kernel, but more testing with the latest systemd code needs to be done first.

If you want more information about the kdbus interface, and how it works, please see the kdbus.txt file for details.

Binder vs. kdbus

A lot of people have asked about replacing Android’s binder code with kdbus. I originally thought this could be done, but as time has gone by, I’ve come to the conclusion that this will not happen with the first version of kdbus, and possibly can never happen.

First off, go read that link describing binder that I pointed to above, especially all of the links to different resources from that page. That should give you more than you ever wanted to know about binder.

Short answer

Binder is bound to the CPU, D-Bus (and hence kdbus), is bound to RAM.

Long answer

Binder

Binder is an interface that Android uses to provide synchronous calling (CPU) from one task to a thread of another task. There is no queueing involved in these calls, other than the caller process is suspended until the answering process returns. RAM is not interesting besides the fact that it is used to share the data between the different callers. The fact that the caller process gives up its CPU slice to the answering process is key for how Android works with the binder library.

This is just like a syscall, and it behaves a lot like a mutex. The communicating processes are directly connected to each other. There is an upper limit of how many different processes can be using binder at once, and I think it’s around 16 for most systems.

D-Bus

D-Bus is asynchronous, it queues (RAM) messages, keeps the messages in order, and the receiver dequeues the messages. The CPU does not matter at all other than it is used to do the asynchronous work of passing the RAM around between the different processes.

This is a lot like network communication protocols. It is a very “disconnected” communication method between processes. The upper limit of message sizes and numbers is usually around 8Mb per connection and a normal message is around 200-800 bytes.

Binder

The model of Binder was created for a microkernel-like device (side note, go read this wonderful article about the history of Danger written by one of the engineers at that company for a glimpse into where the Android internals came from, binder included.) The model of binder is very limited, inflexible in its use-cases, but very powerful and extremely low-overhead and fast. Binder ensures that the same CPU timeslice will go from the calling process into the called process’s thread, and then come back into the caller when finished. There is almost no scheduling involved, and is much like a syscall into the kernel that does work for the calling process. This interface is very well suited for cheap devices with almost no RAM and very low CPU resources.

So, for systems like Android, binder makes total sense, especially given the history of it and where it was designed to be used.

D-Bus

D-Bus is a create-store-forward, compose reply and then create-store-forward messaging model which is more complex than binder, but because of that, it is extremely flexible, versatile, network transparent, much easier to manage, and very easy to let fully untrusted peers take part of the communication model (hint, never let this happen with binder, or bad things will happen…) D-Bus can scale up to huge amounts of data, and with the implementation of kdbus it is possible to pass gigabytes of buffers to every connection on the bus if you really wanted to. CPU-wise, it is not as efficient as binder, but is a much better general-purpose solution for general-purpose machines and workloads.

CPU vs. RAM

Yes, it’s an over simplification of a different set of complex IPC methods, but these 3 words should help you explain the differences between binder and D-Bus and why kdbus isn’t going to be able to easily replace binder anytime soon.

Never say never

Ok, before you start to object to the above statements, yes, we could add functionality to kdbus to have some blocking ioctl calls that implement something like: write question -> block for reply and read reply one answer for the request side, and then on the server side do: write answer -> block in read That would get kdbus a tiny bit closer to the binder model, by queueing stuff in RAM instead of relying on a thread pool.

That might work, but would require a lot of work on the binder library side in Android, and as a very limited number of people have write access to that code (they all can be counted on one hand), and it’s a non-trivial amount of work for a core function of Android that is working very well today, I don’t know if it will ever happen.

But anything is possible, it’s just software you know…

Thanks

Many thanks to Kay Sievers who came up with the CPU vs. RAM description of binder and D-Bus and whose email I pretty much just copied into this post. Also thanks to Kay and Lennart for taking the time and energy to put up with my silly statements about how kdbus could replace binder, and totally proving me wrong, sorry for having you spend so much time on this, but I now know you are right.

Also thanks to Daniel Mack and Kay for doing so much work on the kdbus kernel code, that I don’t think any of my original implementation is even present anymore, which is probably a good thing. Also thanks to Tejun Heo for help with the memfd implementation and cgroups help in kdbus.

January 15, 2014 08:57 PM

September 03, 2009

Valerie Aurora

Carbon METRIC BUTTLOAD print

I just read Charlie Stross's rant on reducing his household's carbon footprint. Summary: He and his wife can live a life of monastic discomfort, wearing moldy scratchy 10-year-old bamboo fiber jumpsuits and shivering in their flat - or, they can cut out one transatlantic flight per year and achieve the equivalent carbon footprint reduction.

I did a similar analysis back around 2007 or so and had the same result: I've got a relatively trim carbon footprint compared to your average first-worlder, except for the air travel that turns it into a bloated planet-eating monster too extreme to fall under the delicate term "footprint." Like Charlie, I am too practical, too technophilic, and too hopeful to accept that the only hope of saving the planet is to regress to third world living standards (fucking eco-ascetics!). I decided that I would only make changes that made my life better, not worse - e.g., living in a walkable urban center (downtown Portland, now SF). But the air travel was a stumper. I liked traveling, and flying around the world for conferences is a vital component of saving the world through open source. Isn't it? Isn't it?

Two things happened that made me re-evaluate my air travel philosophy. One, I started a file systems consulting business and didn't have a lot of spare cash to spend on fripperies. Two, I hurt my back and sitting became massively uncomfortable (still recovering from that one). So I cut down on the flying around the world to Linux conferences involuntarily.

You know what I discovered? I LOVE not flying around the world for Linux conferences. I love taking only a few flights a year. I love flying mostly in the same time zone (yay, West coast). I love having the energy to travel for fun because I'm not all dragged out by the conference circuit. I love hanging out with my friends who live in the same city instead of missing out on all the parties because I'm in fucking Venezuela instead.

Save the planet. Burn your frequent flyer card.

September 03, 2009 07:04 AM

March 04, 2013

Twitter

March 01, 2013

Twitter

February 18, 2009

Stephen Hemminger

Parallelizing netfilter

The Linux networking receive performance has been mostly single threaded until the advent of MSI-X and multiqueue receive hardware. Now with many cards, it is possible to be processing packets on multiple CPU's and cores at once. All this is great, and improves performance for the simple case.

But most users don't just use simple networking. They use useful features like netfilter to do firewalling, NAT, connection tracking and all other forms of wierd and wonderful things. The netfilter code has been tuned over the years, but there are still several hot locks in the receive path. Most of these are reader-writer locks which are actually the worst kind, much worse than a simple spin lock. The problem with locks on modern CPU's is that even for the uncontested case, a lock operation means a full-stop cache miss.

With the help of Eric Duzmet, Rick Jones, Martin Josefsson and others, it looks like there is a solution to most of these. I am excited to see how it all pans out but it could mean a big performance increase for any kind of netfilter packet intensive processing. Stay tuned.

by Linux Network Plumber (noreply@blogger.com) at February 18, 2009 05:51 AM

September 25, 2010

Andy Grover

Plumbers Down Under

<p>Since the original <a href="http://www.linuxplumbersconf.org/">Linux Plumbers Conference</a> drew much inspiration from <a href="http://lca2011.linux.org.au/">LCA</a>'s continuing success, it's cool to see some of what Plumbers has done be seen as <a href="http://airlied.livejournal.com/73491.html">worthy of emulating at next year's LCA</a>!</p><p>LCA seems like a great opportunity to specifically try to make progress on cross-project issues. It's quite well-attended so it's likely the people you need in the room to make a decision will be <em>in the room</em>.</p>

by andy.grover at September 25, 2010 01:50 PM

September 10, 2010

Andy Grover

Increasing office presence for remote workers

<p>I work from home. My basement, actually. I recently read an article in the Times about <a href="http://www.nytimes.com/2010/09/05/science/05robots.html?_r=1&amp;pagewanted=1">increasing the office presence of remote employees with robots</a>. Pretty interesting. How much does one of those robo-Beltzners cost? $5k? This is a neat idea but it's still not released so who knows.<br /><br />I've been thinking about other options for establishing a stronger office presence for myself. Recently I bought a webcam. If I used this to broadcast me, sitting at my desk on Ustream or Livestream, that would certainly make it so my coworkers (and the rest of the world) could see what I was up to, every second of the workday. This is actually a lot <i>more</i> exposure than an office worker, even in a cubicle, would expect. If I'm in an office cube, I might have people stop by, but I'll know they're there, and they won't <i>always</i> be there.&nbsp; There is still generally solitude and privacy to concentrate on the code and be productive. I'm currently trying something that I think is closer to the balance of a real office:<br /><ul><li>Take snapshots from webcam every 15 minutes<br /></li><li>Only during normal working hours</li><li>Give 3 second audible warning before capturing</li><li>Upload to an intranet webserver</li></ul>I haven't found this to be too much of an imposition -- in fact, the quarter-hourly beeps are somewhat like a clock chime.<br /><br />In the beginning, it's hard to resist mugging for the camera, but that passes:<br /><img style="max-width: 800px;" src="http://oss.oracle.com/%7Eagrover/pics/blog/whassup.jpg" alt="whassup???" height="240" width="320" /><br />Think about how this is better than irc or IM, both of which <i>do</i> have activity/presence indicators, but which either aren't used, or poorly implemented and often wrong. How much more likely are you, as a colleague of mine, to IM, email, video chat, or call me if you can see I'm at my desk and working? No more "around?" messages needed. You could even see if I'm looking cheerful, or perhaps otherwise indisposed, heh heh:<br /><img style="max-width: 800px;" src="http://oss.oracle.com/%7Eagrover/pics/blog/cat1.jpg" alt="hello kitty" height="240" width="320" /><br />On a technical note, although there were many Debian packages that kind-of did what I wanted, it turned out to be surprisingly easy to roll my own in about <a href="http://github.com/agrover/pysnapper/blob/master/webcam.py">20 lines of Python</a>.<br /><img style="max-width: 800px;" src="http://oss.oracle.com/%7Eagrover/pics/blog/working.jpg" alt="working hard." height="240" width="320" /><br />Anyways, just something I've been playing around with, while I wait for my robo-avatar to be set up down at HQ...</p>

by andy.grover at September 10, 2010 05:20 PM

November 08, 2009

Valerie Aurora

Migrated to WordPress

My LiveJournal blog name - valhenson - was the last major holdover from my old name, Val Henson. I got a new Social Security card, passport, and driver's license with my new name several months ago, but migrating my blog? That's hard! Or something. I finally got around to moving to a brand-spanking-new blog at WordPress:

Valerie Aurora's blog

Update your RSS reader with the above if you still want to read my blog - I won't be republishing my posts to my new blog on this LiveJournal blog.

If you're aware of any other current instances of "Val Henson" or "Valerie Henson," let me know! I obviously can't change my name on historical documents, like research papers or interviews, but if it's vaguely real-time-ish, I'd like to update it.

One web page I'm going to keep as Val Henson for historical reasons is my Val Henson is a Man joke. Several of the pages on my web site were created after the fact as vehicles for amusing pictures or graphics I had lying around. In this case, my friend Dana Sibera created a pretty damn cool picture of me with a full beard and I had to do something with it.



It's doubly wild now that I have such short hair.

November 08, 2009 11:36 PM