Josef “Jeff” Sipek


Doug Engelbart Institute — Online exhibits, historic videos, texts, archive photos, and stories about Doug Engelbart, the inventor of the mouse, hypertext, and GUIs…all in the 1960s

Flight recorders data inspection by Airbus

Parsing JSON is a Minefield

Completely Painless Programmer’s Guide to XYZ, RGB, ICC, xyY, and TRCs — Brain-hurting amount of information about color profiles, etc.

darktable — A Lightroom-like open source software

World plugs — Info about every electric plug form factor in the world

Visiting Helsinki

Back in July and August I got to visit Helsinki. Needless to say, I dragged my camera and lenses along and did some sightseeing. Helsinki is a relatively new but welcoming city.


My first trip there was in early July (7th-10th). This meant that I was there about two weeks after the summer solstice. At 60°10’ north, this has been the northernmost place I’ve ever been. (I’m not really counting the layover in Reykjavik at 63°59’ north, although I do have an interesting story about that for another time.) If you combine these two relatively boring facts (very far north and near solstice timing), you end up with nearly 19 hours of daylight! This gave me ample time to explore. Below are a couple of photos I took while there. There are more in the gallery.

Approaching Wikipedia article: Senate Square and the Wikipedia article: Helsinki Cathedral:

The cathedral:

Not far from this (Lutheran) cathedral is an Eastern Orthodox cathedral—Wikipedia article: Uspenski Cathedral.

And here is its interior:

Like a number of other cities in Europe, Helsinki is filled with bikes. Most sidewalks seem to be divided into two parts—one for walking and one for biking. The public transit seems to include bike rentals. These rental bikes are very…yellow.


On Saturday, July 9th, I took a ferry to the nearby sea fortress—Wikipedia article: Suomenlinna—where I spent the day.

Of course there is a (small) church there. (You can also see it in the above photo in the haze.) This one has a sea-fortress-inspired chain running around it.

The whole fortress is made up of six islands. This allows you to see some of the fortifications up close as well as at some distance.

There are plenty of small buildings of various types scattered around the islands. Some of them are still used as residences, while others got turned into a museum or some other public space.


The August trip was longer and consisted of more roaming around the city.

The Helsinki Cathedral in the distance.

There are a fair number of churches—here is the Wikipedia article: Kamppi Chapel.

Heading west of the city center (toward Wikipedia article: Länsisatama) one cannot miss the fact that Helsinki is a coastal city.

Finally, on the last day of my August trip I got to see some sea creatures right in front of the cathedral. They were made of various pieces of plastic. As far as I could tell, this art installation was about environmental awareness.

I took so long to finish writing this post that I’ve gotten to visit Helsinki again last month…but more about that in a separate post. Safe travels!


Last week I got to spend a bit of time in NYC with obiwan. He’s never been in New York, so he did the tourist thing. I got to tag along on Friday. We went to the Statue of Liberty, Ellis Island, and a pizza place.

You may have noticed that this post is titled “Biometrics,” so what’s NYC got to do with biometrics? Pretty simple. In order to get into the Statue of Liberty, you have to first surrender your bags to a locker and then you have to go through a metal detector. (This is the second time you go through a metal detector — the first is in Battery Park before you get on the boat to Liberty Island.) Once on Liberty Island, you go into a tent before the entrance where you get to leave your bags and $2. Among the maybe 500–600 lockers, there are two or three touch screen interfaces. You use these to rent a locker. After selecting the language you wish to communicate in and feeding in the money, a strobe light goes off blinding you — this is to indicate where you are supposed to place your finger to have your finger print scanned. Your desire to rent a locker aside, you want to put your finger on the scanner to make the strobe go away. Anyway, once the system is happy it pops a random (unused) locker open and tells you to use it.

What could possibly go wrong.

After visiting the statue, we got back to the tent to liberate the bags. At the same touch screen interface, we entered in the locker number and when prompted scanned the correct finger. The fingerprint did not get recognized. After repeating the process about a dozen times, it was time to talk to the people running the place about the malfunction. The person asked for the locker number, went to the same interface that we used, used what looked like a Wikipedia article: one-wire key fob near the top of the device to get an admin interface and then unlocked the locker. That’s it. No verification of if we actually owned the contents of the locker.

I suppose this is no different from a (physical) key operated locker for which you lost the key. The person in charge of renting the lockers has no way to verify your claim to the contents of the locker. Physical keys, however, are extremely durable compared to the rather finicky fingerprint scanners that won’t recognize you if you look at them the wrong way (or have oily or dirty fingers in a different way than they expect). My guess the reason the park service went with a fingerprint based solution instead of a more traditional physical key based solution is simple: people can’t lose the locker keys if you don’t use them. Now, are cheap fingerprint readers accurate enough to not malfunction like this often? Are the people supervising the locker system generally this apathetic about opening a locker without any questions? I do not know, but my observations so far are not very positive.

I suspect more expensive fingerprint readers will perform better. It just doesn’t make sense for something as cheap as a locker to use the more expensive readers.

Private Pilot, Honeymooning, etc.

Early September was a pretty busy time for me. First, I got my private pilot certificate. Then, three days later, Holly and I got married. We used this as an excuse to take four weeks off and have a nice long honeymoon in Europe (mostly in Prague).

Our flight to Prague (LKPR) had a layover at KJFK. While waiting at the gate at KDTW, I decided to talk to the pilots. They said I should stop by and say hi after we land at JFK. So I did. Holly tagged along.

A little jealous about the left seat

I am impressed with the types of displays they use. Even with direct sunlight you can easily read them.

After about a week in Prague, we rented a plane (a 1982 Cessna 172P) with an instructor and flew around Czech Republic looking at the castles.


I did all the flying, but I let the instructor do all the radio work, and since he was way more familiar with the area he ended up acting sort of like a tour guide. Holly sat behind me and had a blast with the cameras. The flight took us over Wikipedia article: Bezděz, Wikipedia article: Ještěd, Wikipedia article: Bohemian Paradise, and Wikipedia article: Jičín where we stopped for tea. Then we took off again, and headed south over Wikipedia article: Konopiště, Wikipedia article: Karlštejn, and Wikipedia article: Křivoklát. Overall, I logged 3.1 hours in European airspace.

Saint Paul, Minnesota

Holly and I went to Minnesota four weeks ago. We stayed at Crowne Plaza in downtown Saint Paul and had enough free time to explore the city and its surroundings a bit. The weather was great, so the photos ended up pretty good looking. You can jump to the whole photo gallery or just look at the select few photos below.

The first day of exploring was pretty brief. We spent about two hours total exploring the other side of the Mississippi river. We found a place with a nice view of the whole downtown Saint Paul. Aside from the hotel from across the Mississippi river

and a bird of some sort (I have no idea what kind of bird this is) that was enjoying the updraft from the breeze hitting the river bank and turning up the steep hill side

I got enough shots to make a panorama of downtown. It is about 270 degree field of view! (I have a 14MB JPEG for those wishing to see all the details.)

On the way back to the hotel, we saw this old (and steep) stair case:

Here’s a shot of the bridge up close. Did I mention that the weather was great?

The next day, we didn’t explore since we didn’t have much time. However in the evening the Wikipedia article: mayflies took over the skies. It was amazing and annoying at the same time. The next morning, we went for breakfast and saw dead mayflies everywhere.

After breakfast we went on to explore the city a bit more. We immediately noticed that the whole city seemed deserted. Businesses just didn’t open on Sundays, after an hour of walking around we ran into maybe 5 people total.

Eventually, we asked a security guard what was going on. He said that downtown Saint Paul has enough government offices that the whole city more or less lives Monday to Friday, 9am to 5pm.

Eventually, we made it to the capitol hill — the capitol is on a hill. Again, I couldn’t resist the temptation to make a panorama. This time it is only 180 degrees wide. (17MB JPEG)

Then I climbed up the stairs, and took enough for a third (and final) panorama. Again, about 180 degrees wide. (9MB JPEG)

Afterwards, we mosied on toward the Saint Paul Cathedral. (Our last stop before going to the hotel to grab the bags and heading to the airport.)

There is a bunch of photos in the gallery that I didn’t include this post. That concludes this edition of “Travels with Jeff & Holly.”

OLS 2008 - Day 1

Times has come once again to talk of Ottawa Linux Symposium. Yep, that’s right it’s that time of the year again (ok, I’m posting it a little bit late).

Today was mostly uneventful. I woke up just before 6, got to the airport, flew to Ottawa, got to the hotel, realized I was about 4 hours early for check-in. I left my bag at the hotel, and went to the conference center. There I ran into Christoph Lameter. Having nothing better to do, we decided to pick up our registration and then go eat something.

When I got to the airport (LaGuardia) in the morning, I went on to continue reading a book I was about 2/3 of the way through — Princess Bride. My reading got briefly interrupted by the boarding call. After boarding the plane, I resumed reading. There is one really nice property these paper things have over electronic ways of eating up time…they don’t need to be turned off for take off and landing. Anyway, I fished the book while waiting for the hotel shuttle at the Ottawa airport. For what it’s worth, it’s a good book that everyone should read.

Around 6pm, a bunch of people I know (but probably shouldn’t associate myself with them in public ;) ) got to the hotel…about 2 hours later, one of them, a weather-loving KDE code monkey (yeah, that’s you Shawn) and I ordered pizza. It was quite tasty, as were the chicken pieces in the blue-cheese sauce.

Anyhow, time to run to the next talk….I’ll try to post at least once a day with random stuff…we’ll see how that goes.


As many of you may have noticed, I’ve been really lazy when it comes to updating this blahg of mine…so here’s a short summary of what happened over the past week at SC07. I’m sure I forgot to talk about a ton of things…feel free to leave a comment.

Friday, November 9

Pretty uneventful day…flying from JFK to Reno via LAX, checking into the hotel were the two highlights.

Saturday, November 10

We mis-read the bus schedule, and ended up taking the 6:30 shuttle to the convention center. Waking up that early was quite painful. When we got to the center, we started unpacking the nodes, rack and the TV. Compared to the other teams, we were unfortunate enough to have twelve 8-core nodes, and two 4-core nodes. Yeah, 14 nodes, an infiniband switch, a gigE switch, a TV, and the full-sized rack. That’s 18 things to unpack. Other teams had around 8 nodes and similar interconnect. Either way, we had more to set up.

The organizers of the Cluster Challenge (this is the whole thing about universities, and teams, Stony Brook being one of them - read the link for more info) were nice enough to organize a cruise on lake Tahoe for us…but the only problem with it was, that it was in the evening. So, we got to see a whole lot of big black nothing.

Majority of the Indiana University team, featuring Pikachu:

Majority of the Indiana University team, featuring Pikachu

I must admit, the pikachu hat was a great way to draw attention, I therefore propose that next year, the team looks more like this (photo courtesy of Peter Honeyman):


Sunday, November 11

While most of Saturday was spend setting up hardware, at least half of Sunday was spend setting up software. Somehow, magically, NFS decided to stop working (I’ve been told by the NFS folks that it’s generally not NFS that breaks but something else, but I maintain that NFS is broken :) ). In our case, NFS was a major component - we went the netboot way, and had only 1 disk for the entire cluster. We exported the node root directory image, as well as the home directories over NFS over ethernet, and created a tmpfs (kind of like a ramdisk, but it grows as needed) over NFS over IP over IB. There’s probably a way to remove IP out of the equation, but we just didn’t have enough time to try everything we wanted to - like doing PXE boot over IB, removing the need for ethernet all together. (One of the visitors who stopped by our cluster told me that he does do netboot over IB.)

Stony Brook’s rack

Monday, November 12

The Cluster Challenge started at 20:00. Things got really hectic really quickly, but overall it was all fun. Once everything calmed down, we decided to start the 6-hour shifts. I went back to the hotel. At 4:13 in the morning, I got woken up by a call from the team leader asking me when I’d be back. 4:13 is waaaay too early. I decided to take a pillow and the blanket with me to the conference center.

Colorado team

About 19.5 hours later, still at the conference center, I decided to go to sleep. I didn’t feel like going back to the hotel, so I crashed on one of the couches right by our team’s rack. I hear there is a photo of me sleeping on the couch. Moral of the story: when at a conference, take a pillow and a blanket with you, it might come in handy when you decide to sleep at the conference center.

Tuesday, November 13

Shortly after noon, the entire conference center lost power for a couple of seconds (see The Register). None of the teams were using UPSes (UPSes eat up power, which was quite precious - only 26 Amps per team), all the clusters rebooted. I’ve heard that the team from Taiwan lost more than 10 hours of computation because of that.

Taiwan team

We lost only about 15 minutes wall time of computation (on 96 cores) because we just started a new job.

Taken right after the power outage (notice that the lights are still off):

Right after the power outage, it took them a while to turn back the lights

Wednesday, November 14

The competition ended at 16:00. That’s 44 hours after starting. Everyone was quite tired, but not tired enough to skip what the conference organizers have prepared for us. They rented out an entire arcade in one of the near by hotels. The arcade included a whole lot of games, including laser tag. I wish I had a photo of one of the signs at the laser tag place, because it had quite a number of grammatical mistakes.

Purdue team

Thursday, November 15

Judging/organizer station

The conference ended at 16:00. Everything got promptly torn down, and packed up in boxes. And then…*drumroll* everyone headed to a Blue Man Group show done specifically for SC07 tech badge holders (which included the folks doing the Cluster Challenge - read: us). The show was fantastic, but far too short. Next time I have a pile of PVC pipes, I’m going to have a ton of fun :)

Friday, November 16

After an hour meeting at the center to figure out what could be done better next year, everyone dispersed, and went their own ways. We went to the airport, and headed back to NY - this time via Phoenix. We got to JFK around midnight.

OLS 2006 - day 1

So, the first day here in Ottawa is about to end. I didn’t do all that much simply because I was tired - I actually fell asleep for few hours, which helped a lot as I had only about 4.5 hours of sleep before heading to the airport. In the afternoon, I found Rik van Riel and Matt Domsch. We chatted a bit. Anyway, I’m going to get some food.

And So The Quest Began Once Again

Almost a year after returning from his quest, brave Sir Jeff decided that ’tis was time to return to the land of Canada. And so the quest began once again.

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