Cold Aisle Containment in our server room

On Thursday 10 March 2011, we installed a so-called Cold Aisle Containment in the server room shared by the Department of Computer Science and HIIT. This is a rustic contraption made from transparent PE plastic, air-conditioning tubes, and a great deal of duct tape. It cuts back on the need to cool the server room very efficiently, as the air-tight plastic stops the intake and exhaust air from the servers from mixing.

After: http://www.youtube.com/watch?v=jZIuJIVYsDs
Before:   http://www.youtube.com/watch?v=ufb0PkCal2k

I videoed the setup before the change and after. The video may look like our server room is starting to resemble one of those biospheres that were popular in the 1990s. The advantage with transparent plastic as building material is that it puffs out with pressure, so now our maintenance team can monitor the cooling capacity of the computer room air conditioners (CRAC) by keeping an eye on the surface of the plastic. In this way, the CRACs will produce exactly as much cool air as the servers need.

Before installing the plastic bubbles in the server room, the CRACs were running full blast all the time. One of them pushed 15-degree (C) intake air under the floor, which became 19-21 degrees when it hit the servers because of the mixing of the air flows.At the end of our three hours of hard work this changed considerably, as the flow of exhaust air became more efficient, making work in the server room much more humane.

The intake air to the servers used to be 20 degrees, but now we need much less cooling capacity. We were able to shut down one CRAC completely and crank up two others 7 degrees. To adjust the last two devices, we need some special tools that we are still waiting for. We will continue to adjust the CRACs, as we are aiming at intake air of 22 degrees and to turn off one more CRAC unit.

Servers in the cold

In addition to optimising the server room, we have been running (other) servers outside since February 2010. At this moment, there is a 26U rack placed on the roof terrace of Exactum. It is protected from water and snow by a kind of cell. You can admire its winking lights at night in the images from the Exactum camera:

Near: http://www.cs.helsinki.fi/u/tkt_cam/exactum_terrace.jpg
Afar:  http://www.cs.helsinki.fi/u/tkt_cam/exactum.jpg

We are monitoring the servers constantly, and they are part of the Folding@home calculation. In addition, anyone can ask about the inner temperatures of the servers via a Twitter feed set up to monitor them. Twitter is in a state of perpetual beta, so more features are on the way.

Twitter:      http://twitter.com/HelsinkiChamber
Folding@home: http://fah-web.stanford.edu/cgi-bin/main.py?qtype=teampage&teamnum=200947

The intake server air is not filtered in any way. The most frequently asked question is, whether the moisture condensing inside the servers harms them. However, the condensation works in reverse, since the servers are cooled by air, so they are always warmer than the air around them. The next most frequent question is whether we could build a sauna with the exhaust air from the servers. We will return to this question in the near future.

If this or any other projects seem interesting to you, you can learn more on Thursday 17 March at the event "Science in the best of company" during the demo session at 17:30-20.

 

- Researcher Mikko Pervilä

You can also follow our research in our blog at http://blogs.helsinki.fi/pervila/.

Created date

17.03.2011 - 13:35

Inter-university research and training centre on information security

The University of Helsinki and Aalto University have set up a joint research centre focusing on information security. The new centre, HAIC (Helsinki-Aalto Centre for Information Security), will coordinate the Master’s-level security education between the university and Aalto, with links to research and doctoral education.

The idea is to build bridges to the industries and gain their support for the education, and e.g. grants for MSc students coming from outside the EU, the head of the Department of Computer Science, Sasu Tarkoma, says.

Computer science undergraduate Petteri Timonen awarded in US science competition

Petteri Timonen, 19, came second in his category of the Intel International Science and Engineering Fair (ISEF) in Phoenix, Arizona.

 

On Friday, 15 May, Timonen, who is studying computer science at the University of Helsinki, was awarded a grant worth 1500 USD, some 1330 euros, in the Systems Software category of the Intel ISEF science competition.
 
As his entry, Timonen submitted a software tool he developed for Finland’s Red Cross to make mobile blood runs around the country as cost-effective as possible. Timonen implemented his tool in cooperation with the Blood Service.

The tool has gained international attention, as no tool like it seems to have been developed anywhere else. Timonen has also negotiated with the American Red Cross by email.

Renewed Carat App Gives a Smart Boost to Battery

 
The Carat Project Team at the University of Helsinki, Department of Computer Science, has published a new version of the popular mobile energy-awareness application.

After launch in June 2012, Carat has helped over 850,000 users, of which 41 per cent have been Android and 59 per cent iOS users, respectively. The new user interface follows modern application design guidelines and presents battery information in a more intuitive and easy to use manner.

- In addition to the new user interface, we have increased the accuracy of the energy saving recommendations of Carat, says Professor Sasu Tarkoma, the leader of this research done at the university.

The user interface features the number of energy intensive applications (Hogs), energy anomalies (Bugs) and user recommendations (Actions) at a glance on the main screen as well as global energy statistics for the device community.

Cover Song Identification Using Compression-based Distance Measures

M.Sc. Teppo E. Ahonen will defend his doctoral thesis Cover Song Identification Using Compression-based Distance Measures on Friday the 1st of April 2016 at 12 o'clock in the University of Helsinki Exactum Building, Auditorium CK112 (Gustaf Hällströminkatu 2b).  His opponent is Academy Professor Petri Toiviainen (University of Jyväskylä) and custos Professor Esko Ukkonen (University of Helsinki). The defence will be held in Finnish.

Measuring similarity in music data is a problem with various potential applications. In recent years, the task known as cover song identification has gained widespread attention. In cover song identification, the purpose is to determine whether a piece of music is a different rendition of a previous version of the composition. The task is quite trivial for a human listener, but highly challenging for a computer.