Yet another goodbye

For those who are about to halt -p, we salute you.

I’m moving out – of my first vserver that is.

I have had the server running for, well

lucretia:~# uptime 
 19:19:59 up 700 days, 22:51,  2 users,  load average: 0.02, 0.06, 0.02

Wow.. Time flies.

I have been migrating the services running in the machine to another, server. Not is the time to do the inevitable.

Sorry old chap, better you than me.

lucretia:~# halt -p

Broadcast message from root@lucretia (pts/1) (Fri Sep 30 19:23:24 2011):

The system is going down for system halt NOW!
lucretia:~# Connection to lucretia.greenpc.dk closed by remote host.
Connection to lucretia.greenpc.dk closed.

Of course, prior to this, I made sure to make a complete copy of the file system like so. Isn’t rsync the best tool?

rsync --progress -poazuHK -e ssh --delete --exclude /proc --exclude sys --exclude dev / home.greenpc.dk:/mnt/primary/backup/lucretia.greenpc.dk

Letting go

It pains me to let my N900 go. We have been together for almost two years now – but I have to move on.

I can still remember the unwrapping of the shiny Nokia box back in that gentle, fresh late-autumn morning back in November ’09.
Moving from a Sony Ericsson K800i, this was a large leap for me, and the N900 would be the phone that introduced me to the world of smartphones.

Suddenly I could do anything! I had a big screen where I could surf the high seas of the treacherous internet. And even with Flash content.
I was able to check anything, anywhere. I was king of information and technology.

As the N900 was build around my favourite Linux distribution; Debian, I felt right at home. A had a busybox and and xterm. This was not just a phone – it was a mini-computer with a built-in phone.

N900 and me hit it off – big time. We went everywhere together, did everything together.

Until…

I was appointed project manager of an Android programming project. I obviously needed a device for the development process (at least that was what I told myself).
For that purpose I bought a HTC Wildfire. This was the first step towards the end.

I could not help being drawn towards the much smoother interface of the HTC phone, despite the lower resolution on the Wildfire compared to the N900.

Suddenly my N900 did not seem so smart anymore. A lot the tasks that was difficult and hacky to do on the N900, was integrated in the to the user interface of the Wildfire.

Last week we broke up definitely. I found my new phone at a cheap Danish phone reseller, at lowered price.
Now I have a HTC Desire Z, because I would the Qwerty keyboard too much.

Still, I is  sad – to let a trusty life companion go.

Is ZFS overly hyped?

When ZFS first appeared, it was well received and praised.
The time was ripe for a modernization of file systems to eliminate the tedious task of having to plan and create volume groups.

My first experience with ZFS was when I was hired to build a NAS for a small business.
Initially, I chose to go the tradtional way and make the raid as a raid5. This took ages (about a day) to complete.
I therefore quite surprised when I saw the difference between creation time of a traditional raid5 and a raidz. The raidz was ready seconds after I had created it.

Also, when my server drowned ZFS helped my to salvage my data very easily .

So, what are the cool things about ZFS:

  • Creating raids take seconds insteads of hours (days)
  • It has filesystem level data integrity
  • Built-in snapshots that uses copy-on-write to preserve disk space. It’s like Apple’s Time machine – only on filesystem level
  • The L2ARC feature is brilliant. I have not yet had a chance to try it out yet though.

I know btrfs is said to be the upcoming zfs killer, but from what I have read, it still lacks most of the features that are fundamental for zfs now – and has been for some time.
The advantage of btrfs is that it has the potential of being a clean room implementation of zfs, addressing some of the design flaws that zfs has.

I’ve only seen the tip of the iceberg, and for all my usage it has proved itself more than worthy. I am still trying to convince a business partner to engage in a more bold and lager scale zfs implementation, but this is still in the idea stage.

The next step for file systems will probably be more from the userspace perspective. Modern computers, like the ipad requires a different filesystem layout – or none at all. The next evolutionary step for file systems will be metadata-driven, and storage will be a large pool distributed over different mediums, like cloud based storage.

The applicability of ZFS is enormous – and in my opinion the only thing holding people back is the lack of trust in the technology.
Even though, its technology as I like it best. Complexity made simple – with rich opportunity to dive into the sea of technical details. So to answer my own question; no, I don’t think

Endnu en ubrugelig valgprognose

Som tidligere omtalt byggede vi på min tidligere uddannelse et stemmesystem med det formål at stille entry- og exitpolls tilgængelig ved et lokalt valgmøde.

Valgmødet foregik i Nykøbing F. og var primært rettet mod unge under 18. Det var altså rent teoretisk.

Vi gjorde os dengang følgende observationer:

Resultat før mødet

Man kan tydeligt se en tendes til en højredrejning i prognosen baseret på stemmer indsamlet ved indgangen.
Til gengæld bliver billedet markant anderledes ved udgangen. Det skal bemærkes at stemmeterminalerne først blev aktiveret ved mødets afslutning, og derfor kun repræsenterer meningsfordelingen hos de “vælgere” der deltog i hele mødet.

Resultat efter mødet

Ud over at en stor del (ca. 50%) af deltagerne har forladt mødet viser tallene også at der nu er en kraftig venstreskæv fordeling – især til Enhedslisten der er gået markant frem.

Både Venstre og Socialdemokratiet er gået tilbage. Dansk Folkeparti er det parti der har lidt størst tab under mødet; ud af de 114 stemmer de fik ved indgangen, er 100 vælgere enten udvandret eller har skiftet mening.

Jeg syntes observationene er interessante, men de har jo intet at gøre med det forestående valg. Måske andre kan hive flere spændende konklusioner ud fra disse tal?

Til de kodeinteresserede kan serverdelen og kommandolinje klienten hentes her:

valgsystem.tar.gz

Politiske partilogoer i svg format

I forbindelse med konstruktionen af et valgsystem tilbage i 2007 havde jeg brug for de enkelte partiers logoer i et vektorbaseret format – da det ikke var alle der havde den slags liggende, gav jeg mig i kast med at kreere dem selv.

Nu da der atter er valg, kan nogen måske få nytte af dem.

De er alle manuelt tracet i inkscape af undertegnede og i svg format.

politiske_logoer_2007.zip

God fornøjelse.