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Something completely different?

From time to time, you see Chipster popping up in quite surprising ways...

Salvaging hard drives with ddrescue

As a Java programmer, you tend to not be bothered about hardware. Unfortunately sometimes hardware will come and pull out the rug from under you...

Packaging SSH Clients: PuttyTray redux and FileZilla

Secure SHell (SSH) is a popular low-bandwidth protocol to use remote devices via terminal sessions, tunnel connections and more. This post details one way to package open source windows clients for SSH and SFTP/FTP/FTPS (with UTF-8 support) to be distributed in a managed environment.

Data Center presentation

<p>I recently presented a summary of current data center trends and technology to an audience from Jyväskulä University. I wanted to share these slides with the audience because they include some useful links for further information. I'm sure others will find these slides useful.</p> <p>The topics covered include:</p> <ul> <li>What is driving data center innovation? <ul> <li>Web scale computing</li> <li>Economics and Metrics</li> </ul> </li> <li>Air cooling trends</li> <li>Separating hot and cold air</li> <li>Liquid cooling</li> <li>Modular buildings/containers</li> </ul> <p><a href="./resolveuid/24da0a768f0fccee7467c13e757d75ee">Data Center presentation is here (5.7MB PDF)</a></p>

Using Exchange 2007 calendar with Thunderbird plugin

If you have at least Thunderbird 3.0 and the possibility to install extensions, it's possible to use an Exchange 2007 or newer calendar within Thunderbird. The use includes making meetings and seeing other people's free/busy status when making reservations. The required plugin is here (requires lightning and minimum of Exchange 2007): https://addons.mozilla.org/en/thunderbird/addon/provider-for-microsoft-exchang/

Kirjastoaiheinen elämysmatka polkupyörillä

Internetin myötä kaikilla on nykyisin käytettävissään suoraan työpöydällään ennennäkemätön määrä tietoaineistoja. Varsinkin kirjastoalan ammattilaiset ovat tottuneet hyödyntämään monipuolisesti niin uusia kuin perinteisiäkin tietolähteitä. Mitä tapahtuu jos kootaan 80 heistä yhteen reiluksi viikoksi ilman kirjoja ja nettiyhteyttä? Sitä kokeiltiin <a href="http://www.cyclingforlibraries.org">Cycling for Libraries -tapahtumassa</a> pyöräillen 700 km Kööpenhaminasta Berliiniin.

MIDRAS-loppuraportti

Kun tehdään, niin syntyy siitä jotain jälkeäkin.

Mac OS X key bindings in Java

Mac OS X key bindings in Java - How hard can it be? We've found out that our software does not follow all Mac conventions when it comes to keyboards shortcuts. This was a bit of a surprise, as everything has been done "by the book".

Performance comparison of streamed encryption and compression

In the last post I discussed encrypting users' data files when they move around in a distributed system, such as Chipster. The big practical question was not answered: Will it be fast enough? To answer that I did some performance tests and give the results here.

Encrypting and compressing your data on fly

When running a distributed system for data analysis, you have to take the big responsibility for your users' data. While doing development for our Chipster system, we started to think about the question: How to make that big responsibility smaller?

Bleak future of open source in open web?

In a recent issue of the Wired magazine the big theme was: Is the Web dead? The take home message was that the heterogenous collection of independent companies, public institutions and individuals that made up the Web in past has been largely replaced by large centralised services. If open Web is to lose ground for closed systems, will this happen also for open source?

Työkaluja verkon suorituskyvyn testaukseen

Verkon ylläpitäjille ja myös loppukäyttäjille on tarjolla työkaluja, joilla voi testata verkkoyhteyden laatua, jos epäilee niissä joitain ongelmia. Blogin lopussa on pari esimerkkitapausta, jota osoittavat, että verkon suorituskyvyn selvittely kannattaa.

PERT auttaa selvittämään verkkoyhteyden pullonkaulat

PERT-toiminta (Performance Enhancement and Response Team) on Funetin ongelmaselvittelypalvelu, mikä pohjautuu Euroopan tutkimusverkkohankkeen GN3:n ja kansallisista tutkimusverkkojen (NREN, National Research Networks) jo 2004 alkaneeseen yhteistyöhön. Sen avulla pyritään ratkomaan ongelmia, joihin verkon käyttäjät törmäävät nykyisten huippunopeiden tietoliikenneyhteyksien kanssa.

Memory management in modern times

For us application programmers of modern times the canonical advice to memory management has been: don't do it. Trying to be too clever can lead to a serious degradation of performance, unless you are very careful. A couple of recent blog posts got me thinking that things are not so simple after all...

Firefox and Thunderbird updates with user rights

As network-using software, the web browser Mozilla Firefox and email suite Mozilla Thunderbird are especially fit to update themselves and keep vulnerability access time to a minimum. Here's how to configure them for self-updating with user-level rights.

Onnistunut loma

 

Metatiedot, osa 1½: rekisteriaineistojen metatietostandardeja

Ihmiset ja sitä myötä projektit palailevat pikku hiljaa kesälomilta, ja sitä myötä blogiakin voisi päivittää. En kuitenkaan kirjoita tällä kertaa kovin yleisellä tasolla, vaan kerron niistä käytännön metatietoasioista, joista on puhuttu ennen ja jälkeen kesälomien. Erityisesti tarkastelen matriisimuotoisten aineistojen kuvailun standardeja.

How to configure ssh keys on HP C Class blade enclosures

<p>Couldn't find this online so I thought I'd share it here.</p> <p>If you want to add an ssh key to a HP BladeSystem Onboard Administrator do this at the prompt:</p> <pre>&gt; set script mode on<br /><br />Script mode now in effect.<br /><br />[SCRIPT MODE]&gt; add sshkey UnIqUe_StRiNg<br />ssh-rsa realkeyomitted user@hostname<br />UnIqUe_StRiNg</pre> <p>Note that you can't have password and ssh key authentication for a single user so you'll need to create two administration users, one for password auth and one for ssh key.</p> <p>I'll leave the reader to decide what they think of this functionality!</p>

The 1st Implementation Phase of PRACE started

A couple of remarks on the 1st Implementation Phase of the PRACE (Partnership for Advanced Computing in Europe) project from the CSC'er point-of-view.

CSC HPC training curriculum

There will be a set of 1-3 day intense courses which will complete a "A first course in HPC", that is, a no-nonsense introduction to parallel programming and code optimization.