Hi!

This is a post that is relevant to about 0.000000% (o, I forgot a "1"!) of the readers: how to implement the missing dladdr() in AIX5. I could not find it anywhere, nobody seemed to have an implementation - and CINT needs it. So when porting v5.28.00 to AIX5 I needed to deal with it.

To save other people from going mad, here's the code:

Hi!

Build systems belong to the world's most irrelevant things. That is: if they work: if they rebuild the parts that depend on a change, if they work for all platforms, and if they are fast. We are pretty happy with our unspectacular configure && make build system: it gets the dependencies right, and (thanks to cygwin) works on all platforms. But how does it do in terms of speed?

Hi!

I noticed that lately, on Ubuntu 10.10, I dont get any! backtrace! anymore! Nothing! I ran e.g.

root [0] TObject *o = (TObject*)8764586
root [1] o->GetName() 

 *** Break *** segmentation violation
Root > .q

In the past I got a nice stacktrace showing what called what, and that I was supposed to send the crash to myself - and now?

Ubuntu's kernel hardening efforts are causing that:

Hi!

Sorry for having been blog-lazy; first New Year's resolution: more posts.

This time I'll spread two revolutionary news items; they are "officially" public but hey, that doesn't mean everybody knows :-) It's on Rene and Fons, and no, you guessed wrong :-)

Hi!

Welcome to our new server, a blazingly fast 8 core Xeon 5520 with 24GB RAM. Don't tell anyone, but it's not running SLC5... Talking about OSes: Ubuntu Server is a really nice OS.

Hi!

The C++ "0x" draft has been published last week, finally! It might still change, but probably not much.

Hi!

Before ACAT 2010 I spent a week in northern India, visiting e.g. the royal bath of the Kumbh Mela in Haridwar, a 10 million Hindu Ganges bathing event. Scary? Yes. But what an amazing experience!

Hi!

Since version 5.26, ROOT's files are much faster to read; reports regarding ATLAS AODs regularly show a factor 6 speedup. I will explain where this acceleration comes from (or better what stopped previous ROOT files from being that fast) and how you can enable it. Disclaimer: almost all of what I describe here was done by Rene; I only describe his findings and solutions.

Diagnosis

ROOT v5.26 has a new tool that monitors the performance of reading TTrees: TTreePerfStat. Is is used like this:

Hi!

I'm happy to see that the title got you here :-) As a matter of fact, this is about several bugs in ROOT. We had code like

if (!CheckServerIsUp(server)) {
  MarkServerBad(server);
}

That code is just fine, right? Well, read on...

Hi!

Bjarne Stroustrup was here at CERN many weeks ago. In my previous entry I promised to tell you what else we were discussing: threading, symbols and reflection.