Torsten Hoefler’s blog

I visited ETH Zurich at the end of last month. Zurich is probably one of the most beautiful cities in Europe and definitely one of (if not the) most expensive city . Public transit is just a dream, I believe one really doesn’t need a car around the city (I know multiple people who live there and don’t have a car). The city is very hilly (I had to climb 1000 stairs to get from the main train station to my hotel, quite workout ). ETH itself sits majestically on top of a hill and offers a beautiful view. Especially the Professor’s lunch area, on top of the main building has an absolutely stunning view on the city and the lake. I also had many very interesting technical discussions and like the CS department there. Here are some pictures:

The gate to the computer science and chemistry building.

The entrance to the computer science building, all very impressive. The doors must weigh a ton but they are automatic (not like in Chemnitz where one really has to move the heavy doors ).

The majestic main building. I gave my talk here.

View of the city from the main building.

Another view of the city.

Another view of the city.

The main building’s back entrance .

I’ve been at IPDPS in Alaska this week. Actually, not just in Alaska but in *the* city in Alaska, Anchorage! Well, I was shocked, seriously. Achorage supposedly had 300.000 citizens, however, it seemed much smaller than Champaign or Chemnitz! There was really nothing happening there . The mountains in the background are extremely nice, I agree.

The other nice things was that it was effectively light until 12am. It’s really weird when you step out of a bar at 11pm and it’s like noon …. well, one weird thing was that all the natives seem to be drunk after 10pm for some reason. As I said, a strange place!

The conference was amazing! It seemed to me as if I knew every other person. And the IPDPS 25th anniversary show and Moose and Awards sessions were just great (with the right people around ).

This year, I was chairing the HIPS workshop there which also went extremely well! We had 58 attendees during the (excellent) keynote of John Mellor-Crummey!

Unfortunately, I had barely time to visit the wildlife, but we made a small trip. Here are some pictures to get an impression of Alaska (it’s basically like the Alps, nothing too special).

Interestingly, it wasn’t all that cold, around 12-15 degree Celsius. A fun fact is that Monday was colder in Champaign (10 degree Celsius) than in Alaska (14 degree Celsius) .

Yes, I have been there! Eklutna lake, near Anchorage!

Mountains …

More mountains …

View on the city (small, isn’t it?)

Even more mountains …

(Thanks to Jens and Thomas for the pictures, I forgot my camera …!)

This week I have been at the DOE ASCR Exascale meeting in San Diego. It was actually a very nice and informative meeting. I hope the strategy documents will be published soon. We identified a couple of challenges for Exascale (yes, more challenges ).

My flight was in the afternoon of the last day and nobody else was around that afternoon . Well, so I decided to take the local commuter train to Mexico ($2.50 each way ). It’s pretty cool, one usually doesn’t walk across international borders like this. The funny thing was that nobody cared when I walked into Mexico (the officer was sleeping), however, the controls to get back in the US were extremely strict so that there was a line of at least 1000 people and I would have missed my plane if I wouldn’t have walked to the front of the line (which worked surprisingly well).

Here are some pictures:

Apparently, the parking Lot and Mexico are the same direction

Glad that I didn’t come by car, seems like there are more serious controls.

The famous US-Mexican border, well, not too spectacular.

Walking through those prison-bar things is actually fun, and they twist rather fast if you want .

The border stone, not sure why it says something about water commission there??

The only Mexican guard (the immigration officer was sleeping on his chair a bit further but they didn’t want me to take pictures. Too bad. Btw., this guy had a G3 *lol*.

Very very inviting … really. I read that many people are robbed in this area.

But they had a gigantic flag! Viva la Mexico!

Well, time to go home (there was really not much to see actually — but the food was just *awesome*. I love *real* Mexican food now! Cilantro is not that bad if it’s used in the right combination.). Those signs were actually very helpful for dumb tourists like me.

Taco Bell has a branch in Mexico. If they know?

Probably Tijuana’s main sight, well, kinda sad but it’s humongous and the steel rods make funny noises in the wind.

Again, good that I didn’t go by car, the line into the US was hideous and sneaking to the front seems harder by car .

All-in-all an experience that I didn’t want to miss. I didn’t have much time though, but I guess Tijuana is not that touristy in general .

I have been appointed as Adjunct Assistant Professor in Computer Science at UIUC since last year. My first service to the CS department is teaching the lecture CS498 “Hot Topics in HPC: Networks and Fault Tolerance” together with Franck Cappello this semester. It is the first class that I teach in the US academic system and it is a bit different from what we used to do in Germany. Classes are generally smaller (I have around 20-25 students, some of which do not take credit) which enables a more interactive teaching style. In my networking part, I start with focusing on the theoretical foundations and models for communication and then show practical examples for each of them and how the knowledge can help practical setting. I think it’s most important to understand the basics (this is also harder to learn and understand from textbooks than the technical details) before diving into practical networks. Teaching this class has been a lot of fun so far even though the preparations are really weekend-time consuming. I really enjoy the interactions with the students during class.

I’m teaching the class every Wed and Fri 9:30-10:45am in Siebel 1103. If anyone is interested in the content, check out the class webpage at http://www.unixer.de/CS498/ .

Yes, we received the SC10 Best Paper Award for our paper “Characterizing the Influence of System Noise on Large-Scale Applications by Simulation”. Congratulations also to Timo and Andrew! SC10 is the premier international venue for HPC research and development. Only 50 of the 253 submitted papers have been accepted at SC10 and it was very nice to hear that our paper was one of the best paper nominees (each track nominated a best paper), but I didn’t expect that we would be best of all the nominees! The final decision was made after the presentations. My talk was in a way too small room which was completely packed (people were standing at the wall and sitting on the floor in the aisle). The room was “allowed to” host 150 people (sign at the wall) but there were at least 250 in there . Glad that there was no firefighter around. Well, the air got rather bad after ten minutes . The talk itself went extremely well, I was right in time and the audience had a lively discussion that I merely moderated (many questions trying to pinpoint flaws were actually answered by the audience ). That was really enjoyable.

Generally, I really enjoyed SC this year, I have had so many meetings that I was barely able to check the show-floor for goodies. New Orleans was also great (well, my hotel was, let’s say “suboptimal”, but it was very cheap). I’m looking forward to next year!

I am just back from the PROPER workshop in conjunction with EuroPar in Ischia. I have to say that it was absolutely awesome and want to thank my sponsors, Andreas Knuepfer and VI-HPS, again. The joy was even multi-dimensional, first, my keynote went very well and inspired many new ideas. Second, the following talks inspired even more ideas (especially Allen’s presentation). Third, the place was just beautiful (it was somewhat strange to be in a resort among the tourists and talk about CS topics. Fourth, I met many old friends and colleagues and also got to talk to Arnold Rosenberg about graph separators briefly. I loved it even though the travel was very stressful. My travel to Ischia took 25 hours (driving by car to IND, flying to Paris-CDG, flying to NAP, taking the bus to the ferry, ferry to Ischia, Bus to the hotel). The way back was the same order of magnitude. Given that I stayed only 36 hours on the island, the trip seems rather crazy. But hey, I had no jetlag after coming back .

Here are some impressions:
The hydrofoil ferry seemed pretty fast but wasn’t actually. Well, I fell asleep immediately after a 23 hours travel without any sleep.

The room where I presented the keynote .

The food was awesome! Fish, fish and more fish. Even fish-fries (which tasted like french, aehem freedom fries and were somewhat addictive).

The main attraction on Ischia. Well, I didn’t actually find the time to visit it, too much chatting going on … but I’ll probably get there another time.

This year’s Hot Interconnects Conference was very special. Not only was it at Google but I was in the committee as tutorials chair. The conference was very good and I really enjoyed the keynotes and the invited talks on Exascale interconnects and the many conversations I had. The tutorials also went very well. Here are some impressions:

Raj Jain’s Future Internet tutorials.

A Google bike, it looks even funnier when I rode it .

The facility.

Yeah! It worked. One can grow quite attractive Avocado plants from the seeds inside the fruits. It just takes forever (3 months). Here are the results:

Well, I’ve been to Washington more than once, but I finally found the time to actually check out the city (the flight arrived Sunday noon and the first thing on the agenda was Sunday evening ). It’s a very nice city. It’s very nice for walking around and well connected by subway. I did miss the Pentagon though (well, next time ). Here are some pictures:

The workshop was at the FDIC (Federal Deposit Insurance Agency). That was somewhat strange … it didn’t quite look like a hotel but it has an attached hotel (in the large building) and meeting rooms. Kind of cool and highly guarded (one has to check in with security first ).

The white house — it looks much larger in the news. It’s actually really tiny in reality.

The strange guy talking (insulting) trash in front of the house is of course not missing. The Secret Service was also around and didn’t remove him … weird.

They were just standing there.

And of course, the snipers on top of the house . I was expecting that they are hidden better … well.

Heavily armed cars .

This is clearly stolen from Berlin (Siegessaeule)!

The Washington monument. That looks actually much much smaller on TV. It’s really huge in reality. One can go up for free … if one stands in a lint at 8:30 am . How stupid …

Of course, the flags are not missing … the thing in the back is the Lincoln memorial. Quite a bit of a walk.

The WWII memorial, Indiana and Illinois.

The infamous Lincoln.

Korean war memorial, this is really well done.

The capitol on the other side of the Washington memorial.

Nice city!

When I was travelling to Washington today, I had a fun experience at the Indianapolis airport. Well, the first real fun thing is that this stupid CLEAR thing is dead (this was where you could buy yourself into a priority lane at the security checkpoint). Well, the second nice thing was that preferred (status) customers can now use the retired CLEAR lane (yeah, I was at the top of the line ).

However, the TSA officer directed me to a line that lead to a Backscatter X-Ray scanner. So first, I don’t really mind the scanner too much … well, kinda … it takes nice pictures of your girlfriend:

However, there was a huge sign “We respect your privacy and the use of the scanner is optional”. Well, so I decided to not follow the 300 lb guy in front of me (I am wondering if the officers checking the scans get extra pay). The “normal” metal detector right next to it was empty anyway. So what I did was just walk by the officer at the scanner and said that I’ll just use the metal detector instead. Wow, what followed was really unexpected. She shouted “code 5″ at me (as if I knew what that meant) while I proceeded through the metal detector. This apparently meant that I had to go through a manual search … because I refused to use the backscatter x-ray … so much about “optional” and “respect privacy”.

The manual search was really funny. The guy apologized for every single time he touched “sensitive areas” and explained that he would use the back of his hand *lol*. Of course, I kept complaining and eventually talked to the boss of the checkpoint (without much success). He even mentioned that backscatter will not be optional after the testing period. I’ll check Chicago next week but I haven’t seen them there yet.

Update: Btw., Europe is *not* better. Well, at least when you travel to the US. I was going back from Italy through Amsterdam where they had the same things at the gate! Yes, at the gate. Because apparently there are some silly US rules that they have to have a higher security. Refusing to go through was even funnier. So I had a family in front of me and they made the grown-ups go through the scanner while the children were just led through the metal detector (which was closed and they had to turn on for every single use). Well, ok. So I told them that I have concerns about my privacy and health and didn’t want to go through (remember, it’s Europe and there should be some laws … I hope). So they started discussing and showed me the screen of the thing. Well, how could I know what happens to the pictures that were *not* on the screen??? Then they started to explain me that this scanner would work with sonic waves … however, the label clearly said “backscatter” so I didn’t quite trust them. Then I asked why children don’t go through that thing and the answer of the “checkpoint lead” was *very funny*: they’re too small and the scanner can’t reach them. The next thing was that they wanted to deny boarding … fine. I demanded to talk to an airline representative what to do about it and suddenly I got my manual search. They said something in Dutch that I didn’t get … but the search was very thorough. I also had to take my shoes off while everybody else who walked through the scanner that “can’t scan children because they’re too small” did not take their shoes off. Well ,I started arguing again but all I got was “that’s a US regulation”. Very funny. So small terrorists, it’s not rocket science how to game those rules .

Update2: I had four more of those “refusing to go through backscatter” at different US airports … and I have to say that I never went through one. However, I got a private search every single time I refused. And I heard that they’ll be mandatory soon … they also reached Germany (Hamburg) . Well, well, there goes our freedom due to our fears.

Update3: My server is suffering from the fefe effect, so I apologize for any waiting time .

Update4: The picture above is apparently a fake — never trust BILD! Sorry, only in German. (Thanks Hanno)