beep is not useful.

sometimes I get a beep on my laptop. my console has ~10 applications on 9 desktops, including being remotely connected to ~5 machines. a beep without any context is not useful.

POSSIBLE BREAK-IN ATTEMPT (not really)

SSH gives out error messages like this:

Sep 28 09:50:09 s0 sshd[27967]: reverse mapping checking 
                  getaddrinfo for adsl86-34-217-144.romtelecom.net 
                  [86.34.217.144] failed - POSSIBLE BREAK-IN ATTEMPT!

Why does it label it as POSSIBLE BREAK-IN ATTEMPT!? How is it more of a possible break-in attempt than a user attempting to connect more than a few times with a wrong password? This has bugged me a bit recently when helping a few people who aren't really used to linux - its shouting at them that something is SERIOUSLY WRONG!!! and when they look through their log files, they've fixated on this (as far as I can) relatively minor misconfiguration of a remote user's network.

♫ if i could turn back time ♪

Cooker has a one-way-only knob for setting time. You wind forwards until you reach now. If you miss now, you wind forwards another 24h (luckily the cooker doesn't have a date too) until you reach now again. On TZ shift (i.e. end/start of summertime / daylight savings), once per year, there's a wind-forward 1h event. fairly easy. you make the clock run faster than real time. but once per year there's a once per year wind-forward 23h event. BUT! Turns out if you can stop the clock, then you can let real time wind forwards faster than clock time. and wait an hour. and then start the clock again. It involves more real time (you have to wait an hour) but a lot less tedious winding.

wikipedia find-of-the-day: electronic calculator abacus

linked on the wikipedia page for Soroban

5 centuries ago...

I just queued up jobs for a physics simulation that are 5 compute-centuries long:

6 jobs x 11.5 hours x 16384 nodes x 4 cores/node = 5.16 centuries.

I'm expecting the runs to be finished in about a week

If this ran on a single core and I wanted it to be finishing in about a week, I would have had to start them in the year 1495 (the most interesting wikipedia note for that year is Friar John Cor records the first known batch of Scotch whisky).

frustrated-with-slow-simulation haiku

microseconds pass
simulation time stretched
long as winters night

I can't complain too much though - this was 65536 cores on an IBM BlueGene/P

today is blog day

Today is blog day (well, today isn't, it's the 19th of May, but hurrah for autopost)

I'm supposed to recommend 5 blogs to you.

I'm also supposed to find *new* blogs. But FTS, I'm too lazy. Plus I know the ones listed here are ones that I know I go back to day after day and find useful.

Oglaf is some dude's NSFW comic that started out as an attempt at cartoon porn but now is mostly funny. The shield maiden is my favourite post.

Hacker News from ycombinator - kinda like slashdot in that its a lot of interesting geek links. More links. Less discussion. Feels more intimate, and more focused around the bay area startup crowd.

Lambda the ultimate - a programming languages weblog. A cross between programming and maths. If you like Haskell, you'll like this, though all sorts of language stuff (theory, design) is talked about. You can also laugh at the "amusing" paper titles that authors come up with.

In a bit of shameless self promotion, I'll point you at the drupal news feed for my hobby project, barwen.ch - this is partly blog, partly just a web page change tracker.

Finally, Bruce Schneier's security blog. Aside from his tendency to ramble on about squids, this is pretty interesting. It evolved out of his company newsletter, and talks mostly about computer security but also about other related topics such as social engineering and terrorism. And squid.

Exbibyte divergence.

Mostly used by debian crackheads, but slowly becoming more widespread (and apparently also defined by the IEC) is the use of kibibyte to mean a kilobyte measured as 1024 bytes, so that KB can be used to mean kilobyte measured as 1000 bytes. There's a 2.4% difference between the two.

Correspondingly there is Mibibyte, Gibibyte, tebibyte, pebibyte, exbibyte, zebibyte, and yobibyte.

While the difference is only 2.4% at the kibibyte scale, it gets bigger with larger prefixes: by the time you get to petabytes, the scale of the largest file systems I have access to these days, the difference is over 12% and by yobibytes its 20%

brazen sms charging

Its fairly obvious for anyone who thinks about it for a while that SMS is appalling bad value per-byte compared to IP or voice over the same system.

But Orange UK really made me laugh/cry with the brazen way in which they juxtaposed two menu options to make it so clear:

To buy 50 UK SMSes valid for a day for 1 pound, press 1.
 To buy 50 Mb of data valid for a day for 1 pound, press 2.

Yes, 1 UK SMS == 1 Mb of internet data.

W
T
F

y2.1k bug

a decade into this century, and I see plenty of people using 2 digit years. we all know where that's leading...