Josef “Jeff” Sipek

Today is 4th of July...which means fireworks everywhere. Yesterday evening, Jackson, MI had a rather nice display. Here are some of the photos I took:

This past week, Trinity Church (previous post) hosted the AGM. As a result, the NY Times wrote an article about the event and change ringing.

Neat, I just found out that the ringers at Trinity have a new website.

Yesterday, with a group of other people, I went to the Star Trek Exhibition at the Detroit Science Center.

Unforunately, photography is not allowed so if you want to see what it sort of looked like, you'll have to look at the official slideshow.

It was really nice to walk around the bridge of the Enterprise - N C C one seven O one; no bloody A, B, C, or D.

We got a group photo (paid one of course) of the whole bunch of us on the bridge, I might post it when I get a copy of it.

There were plenty of items from all the different series as well as movies - including phasers, tricorders, costumes, ship models, etc., etc.

They had a transporter room (TNG-style), as well as the Guardian (from TOS: The City on the Edge of Forever). We got a group photo with the Guardian as well, I might post it when I get a copy.

Afterwards, we went to see the latest movie in the IMAX they have there. I saw the movie once already (back in May, I think) which was good as some scenes were really hard to follow on such a large screen (e.g., the bar-fight scene).

Overall, it was fun, and if you happen to be near Detroit or Philadelphia you should go and see it before it's over.

Today being 4th of July meant that I could get some fireworks photography going. I was disappointed to find out that Ann Arbor didn't have a fireworks display (or at least I haven't found any information about one). The closest one I could find was in Romulus - about 20 minute drive east on I-94.

The fireworks started around 22:05, and ran for about 25 minutes. Since I managed to not charge up the battery before leaving, the camera let me take only about 40 photos. Below are some of them.

As promised, here's more of the day-by-day summary of Usenix '09.

Friday

The last day of the conference. As before, I got to the place at 8:30, and had breakfast.

The first session, System Optimization, was interesting. It started with Reducing Seek Overhead with Application-Directed Prefetching. The idea is pretty obvious. You have a library that takes lists of future accesses from the application, and tries to prefetch the data while monitoring the application's IO accesses. The first deviation from the prefetch-list causes an invocation of a call-back. This allows the application to specify a new prefetch list.

The second talk of the session, Fido: Fast Inter-Virtual-Machine Communication for Enterprise Appliances, was about a simple and fast way to have multiple VMs communicating. Their target was a collection of virtual machines running in an appliance box. Since the OSes were inherently trustworthy (before virtualization took off and even now, there was one OS that did everything), they achieve zero-copy by mapping all the other OSes into each address space. For example, suppose you have 3 VMs (red, green, blue), their address spaces would be something like:

Each VM gets all the VM's address spaces read-only, and its own read-write. Then a simple message can be exchanged to specify buffer addresses.

The Web, Internet, Data Center session wasn't very exciting. The one talk that stuck in my head was RCB: A Simple and Practical Framework for Real-time Collaborative Browsing. What they did was some javascript-fu that synchronized the DOM trees between two (or more?) browsers.

The last session for the day (and the conference) was Bugs and Software Updates. It opened with The Beauty and the Beast: Vulnerabilities in Red Hat's Packages. The authors did some crazy statistics and found that there was some correlation between packages' dependencies and the number of vulnerabilities. Several audience members pointed out that publishing these findings may cause a feedback that completely maybe either exaggerate this correlation, or it may cause the developers to make dependency choices to make their software seem less likely to have vulnerabilities.

The second talk, Immediate Multi-Threaded Dynamic Software Updates Using Stack Reconstruction sounded interesting, but I really feel like I need to look at the paper first before drawing any further conclusions.

The last talk of the session, Zephyr: Efficient Incremental Reprogramming of Sensor Nodes using Function Call Indirections and Difference Computation, seemed like 2 talks in one. First, we were told about rsync protocol's shortcomings, and how they fixed them, and then we were told about their function call indirection scheme to make the deltas smaller. This function call indirection sounded far too much like dynamically linked binaries, with GOT pointer and all that good stuff.

After a short break, the last invited talk began. The speaker was David Brin - a science fiction writer. He is one of those people that really knows how to present. He gives off an aura of knowing exactly what he'll say next. I can't tell for sure if he does know what he'll say next, or if he merely has an idea where he wants to get to, and "improvises" to get there.

I went back to the hotel, but got bored soon after. Not knowing what to do, I went for a walk. I just took the first street away from the hotel. It turned out to be a road that went considerably uphill toward the San Diego Medical Campus (or whatever it was called). After some exploring, I got some food (this was the only place I saw that had fast food joints, the hotel area was about as boring as it can get).

Saturday

I woke up relatively late - 10am. I blame getting used to the pacific timezone (grr, just in time to fly back!). After packing up, and checking out, I ran into Swami. We went to get breakfast, and talked about all sort of stuff - grad school, conferences, the good ol' days at FSL. After some time, he and another student from Wisconsin took off. I decided to go for a walk. I ended up in the same fast food place. There, I started typing up the previous blahg post. After about 2 hours of working my laptop, I went back and got a shuttle to the airport.

At the airport, I tried to do some work. Before long, I switched to reading a book. Shortly after, it was time to board. The flight itself was mostly uneventful. Sadly, the 2 hour layover in Charlotte, NC was painful. The free wifi that was there few days earlier disappeared. I survived it. Two-ish hours later, we landed at DTW. Due to some miscommunication, I ended up without a ride back to Ann Arbor. I managed to call up a friend that drove me back.

Phew! It's been a fun couple of days. I'm going to provide a day-by-day summary of what's been going on.

Tuesday

More or less the entire day was take up by travel. The flight was mostly uneventful, with a 1 hour layover in Charlotte, NC. The one hour was long enough to get from one terminal to the other and get food, yet short enough that by the time I was done eating, the first class passengers were about to board. For virtually the entire duration of the flight, I was preoccupied with a book I took with me.

Wednesday

Waking up for a 9am event was never easier! I guess it was the timezone difference. Instead of going to bed at about 3am, I went to bed at around midnight (which happens to be 3am on the other coast!).

I woke up at about 6:30 - not due the alarm. I went back to sleep. At 7:30, I woke up for real. Before long, it was 8:30, and I was already at the conference about to get my proceedings and badge. Free food, namely orange juice and crossionts followed.

Nine o'clock rolled around, and the conference began. The keynote was ok. I wasn't amazed by it, even though the speaker had valid points.

At 11, the first session began - virtualization. This was one of the sessions I've been looking forward to. Well, I was interested in one paper specifically: vNUMA: A Virtual Shared-Memory Multiprocessor. The name summarizes the idea very nicely. Why was I interested in it? Well, a long time ago, when you couldn't walk down the street and buy a multi-core system, the year was 2003 - I had the same idea. It's a rather obvious idea, as is the name. At first, I was going to hack the Linux kernel to accomplish it (I still have a couple of patches I started), but other things sapped up my time. (The fact that everyone I mentioned it to told me that the paging over ethernet overheads were going to make it impractical made me want to do it even more!) As it turns out, the folks from University of New South Wales, that got a publication out of it, started working on it in 2002.

Their implementation is for the Itanium architecture. They said that they chose it because at the time they started, Intel was pushing Itanium as the architecture that'll replace x86. Unfortunately, I didn't get to talk to any of them at the conference.

The lunchtime invited talk was nice. It was about how faculty at Harvard tried to make the intro to computer science course fun and appealing, yet still retain the same important intro material. The big thing: they used Amazon's Elastic Compute Cloud (EC2) instead of the on-campus computer network. They liked being in charge of the system (not having to wait for some admin to take care of a request for some change), but at the same time they didn't like being the admins themselves. Some of the students were also not exactly "thrilled" about hearing about the cloud so often - especially since they didn't have to use it in a cloud-way. One of the most memorable parts of the talk was when the speaker whipped out a phone book, asked the audience about how to find something in it, and shortly after proceeded to do binary search - ripping the book in half, then tossing a half across the podium, and then ripping the remainder in half.

Afterward, the networking session took place. The one talk that was fun was StrobeLight: Lightweight Availability Mapping and Anomaly Detection. The summary of the idea: ping the subnet, then some time later, ping it again, and count the number of IPs that changed - essentially XOR and then count ones. It's a simple idea that apparently works rather well.

The next session was about storage. It started with a paper that got a best paper award. One of the authors is Swami - a former FSL member, not at University of Wisconsin-Madison. While he never said it during the talk, they essentially implemented a stackable filesystem. Right after it was a talk by guys from the MIT AI lab, about decentralized deduplication in SAN cluster filesystems.

After a short break, the last invited talk for the day happened. A dude from Sun talked about SunSPOTs. SunSPOT is a small wireless sensor/actuator platform that's based on Java. It reminded me of several other such platforms, but seemed a lot more polished. Unfortunately, it's Java-centric way was rather disappointing. (More or less everyone that knows me, knows that I don't like Java.)

The day concluded with a poster session & food.

Thursday

Again, waking up wasn't a problem. The breakfast happened to be bagels.

9am: the first talk of the distributed systems session, was Object Storage on CRAQ: High-Throughput Chain Replication for Read-Mostly Workloads. This is one of the papers I'm intending to look at. The other two I found less interesting.

11am: the kernel development session had 2 interesting talks. The first, Decaf: Moving Device Drivers to a Modern Language talked about taking device drivers, splitting them into two portions (a performance critical section in C, and a non-performance critical section that could be moved to "a modern language" - read: Java). While I strongly disagree with the language choice, the overall idea is interesting. Java (along with other more managed languages) provides stronger static checking than C. They actually took some Linux drivers, and split them up. I want to go over their evaluation again. The next interesting talk was about executing filesystems in a userspace framework (Rump File System: Kernel Code Reborn). Unlike FUSE and other attempts, this one aims to take in-kernel filesystem code, and execute it in userspace without any modifications.

The lunchtime invited talk about about how teaching students how to program is hard. How some error messages the compiler outputs are completely misleading and confuse students.

I zoned out for most of the 2pm session about automated management. There were emails & other things to catch up on.

The short paper session started off nicely with The Restoration of Early UNIX Artifacts. The speaker mentioned that he managed to get his hands on a copy of first edition UNIX kernel source. While it was slightly mangled up, he managed to get it up and running. After a bit of effort, he got his hands on some near-second edition UNIX userspace. Another short paper was about how Linux kernel developers respond to static analysis bug reports.

The last invited talk for the day was unusual. It was about the Antikythera mechanism. He used Squeak EToys (a Smalltalk environment) to simulate the mechanism. He put the "software" up on the web: http://www.spinellis.gr/sw/ameso/

Afterwards, more food. This time without posters. And after the food, there were some BOFs. The one I went to was about ancient UNIX artifacts. There I got to see first edition UNIX running. Really neat. It felt like UNIX - same but different in some ways. The prompt was '@'; the 'cd' command didn't exist, instead you had 'chdir'... that's right, the "tersness" of UNIX wasn't always there!; the 'rwx' bits you see when you do ls -l were different, you had one 'x' bit, and 2 rw pairs. On my way out, I got more or less dragged into a mobile cluster BOF (or whatever the title was), the most interesting part was when we got to talk about Plan 9 all the way at the end.

About two weeks ago, I went to see a play called Bleeding Red. This was at Purple Rose --- a small theatre in Chelsea, MI.

Their summary of what the play was about says it pretty much all:

In this ball-kicking comedy with adult humor, the biggest football match in twenty years is about to kick off across the pond in London. Tommy, confirmed bachelor and passionate Liverpool fan, arrives at his best mate Bobby's flat to discover he's been dumped by his fiancee. Trouble is, Bobby is the linchpin of the all-important pre-game ritual. Tommy must get him to the pub before the game starts, even if it means recruiting the help of another traitorous female, Bobby's fetching sister Sarah.

Featuring:
Heidi Bennett
Matthew David
Matthew Gwynn
Stacie Hadgikosti
Michael Brian Ogden

Stage Manager: Jessica Garrett
Set Designer: Vincent Mountain
Properties Designer: Danna Segrest
Costume Designer: Sally Converse-Doucette
Lighting Designer: Dana White
Sound Designer: Quintessa Gallinat

Directed by Guy Sanville

It was a nice story. As the story involves Liverpool fans, the actors were doing a Liverpudlian accent.

If you are into comics and happen to be near Chelsea, MI (about 15 mins from Ann Arbor, MI) on June 12 & 13, you might want to consider going to Kids Read Comics comic convention. (As the name implies, it's targeted at a younger crowd but don't get discouraged by that.)

The guest list looks quite good (at least in my opinion).

Yesterday, I went to the anual Roth Pond Regatta at Stony Brook. It's an event where different groups of people race their cardboard and duct-tape boats across a pond. (This was the third time I went, but this year, my participation was limited to taking photos.) Below are some of the more interesting ones, you can always check out the whole gallery (as well as photos from 2007 and 2006; note that the photos haven't been post processed).

The Stony Brook Computing Society's boat:

Some other team's boat...both nice looking and fast:

These folks did not have Dino around:

Gargamel (SBCS member):

Getting the head on:

Papa Smurf! (note the size of the people in comparison):

Another team had fun with special effects:

Then, the races began...

Some boats didn't make it off the starting line:

Others did extremely well:

Papa Smurf is getting old, and isn't as agile as he once used to be:

Gargamel finds it very amusing:

Paddle faster!

Trojans nearing the finish line (note that the boat looks somewhat unfinished - the legs aren't fully painted!)

Papa Smurf getting demolished (part of the rules, once you lose, you must dispose of your boat)

Mummy trying to get to the shore:

The dumpster "guardians" using power-tools on Papa Smurf's head:

This is a very small subset of the photos I took...if you want to see more (un-postprocessed) photos, follow the link near the top of this entry.

I'm a still a day late when it comes to writing about OLS. Here's Friday's list of talks, and other happenings.

The day began with A Practical Guide to using Git (From a Kernel Maintainer) - it was very crowded in the room, so much so that I didn't really see the slideshow, but since I already know enough about how to use Git, I don't mind all that much. Good talk.

The next talk which I kinda had to go to was SynergyFS: A Stackable File System Creating Synergies Between Heterogeneous Storage Devices. It was a disaster - and I put that mildly. The first 30 minutes of the 45 minute talk consisted of Samsung branded marketing material showing that solid state disks were better than the regular platter-based disks. Since the marketing people care mostly about Windows users, the propaganda materials consisted of things like a video thing showing Microsoft Windows Vista booting on two identical laptops - with the exception of the storage device.

Anyway, about 2/3 of the talk through, a SynergyFS got mentioned. And that's when the one quite important bit got mentioned. At the time of the writing of the paper, the filesystem was a "proposed filesystems." In other words, it didn't exist. I am not certain if it exists at the moment, and if it does, what state it is in, but I do know (since an audience member asked when/where he could look at the code) that unless one signs an NDA with Samsung, he can't even look at it. The code is not GPL licensed, since Samsung lawyers apparently see it as a way to lose some magical intellectual property, which as far as I know they never had. There has been papers published about hybrid storage, there have been papers published about fanout stackable filesystems, there have been papers published about fanout stackable filesystems which use different storage technologies (in no particular order: FiST, GreenFS, RAIF, Unionfs).

Overall, I feel like going to the talk was a waste of time. Meh.

Then I lunched.

Well, just before lunch, I was playing around with SELinux on my laptop, and after logging in, the processes weren't getting the right context. After lunch, I went to SELinux for Consumer Electric Devices. I walked into the room, and saw the NSA/Tresys/RedHat SELinux developers (including Dave Quigley) clustered in one area of the room. I just couldn't resist, and I said "SELinux sucks" and then proceeded to walk away. The really amusing thing was all the SELinux people turned around to see who it was that dared to say such a thing. Very amusing. I sat next to them, and mentioned my SELinux problem. Stephen Smalley tried to figure out what the problem was, and in the end, reached the conclusion that somehow, even though the targeted policy was in use, the system was using some information from the strict policy completely confusing everything. I installed the strict policy, and things started working....well, for the most part. I should file this under the Debian bug tracker since it is a bug.

The SELinux talk was ok. It was what I expect...SELinux is kinda bloated for embedded systems. Some time after the talk, I overheard Stephen Smalley talking to Dave, saying that they should look into it a bit.

The next talk which I went to was Around the Linux File System World in 45 minutes. The reason I went to it was because it was being presented by Steve French. It was interesting, as I expected, and I'm going to read through his paper to see what exactly he did for the accounting (and what his thoughts are).

After Steve's talk, I was going to go to a BOF about MIPS kernel port, but got distracted by people (including Steve).

At first, I wasn't sure if I was going to go to the keynote (The Joy of Synchronicity) by Mark Shuttleworth (of the Ubuntu, space travel, and other-random-stuff fame). The title alone makes it sound like a hand-wavy, dreamy thing, but in the end I decided to at least spend 5 minutes listening. It was ok. Not great, from a technical perspective, but he did have some interesting ideas...well, it was really all just one idea - open source projects should have regular release schedules. I don't know if I agree or not. On one hand it's a nice thing, but at the same time, schedules are quite annoying when you want to make major changes (the KDE 3.x to 4.0 changes come to mind). In the end, I did stay the entire time, but I bailed at the beginning of the Q&A session.

Some food later, I headed to the hotel room to finish up writing notes for the day before. Well, I tried to upgrade my Wordpress install...but more about that later.