correct

From a short lecture of this guy, which was very interesting, I tried to crawl internet further.
Taken from the site of weakmemory:

Multiprocessors are now dominant, but real multiprocessors do not provide the sequentially consistent memory that is assumed by most work on semantics and verification. Instead, they have subtle relaxed (or weak) memory models, usually described only in ambiguous (and sometimes flawed) prose, leading to widespread confusion.

Very scary short information. In fact processors specification which is written on their manual are usually written in obscured sentence, instead of in mathematical notation. There are several reasons for that, either they are simply bug, accommodating future changes or avoid patent infringement.

So the lesson from this is to make sure that your code is robust against this obscure features, particularly when you have to deal with critical software.

last posting on this year, and again about computer? what a pity!

Urban Hiking

Yesterday we went hiking to Cercedilla. Very nice, particularly after this very tough week.

I learnt important quote. In hiking sometimes I should look back, watching beautiful scene that I've passed, that might be unseen when I moved advance. I may thankful for how far I have hiked and arrive to certain point, then finally conclude that I shall also reach the peak. However sometimes I should not force myself to reach the peak when there's a sign not to do so, for it may endanger myself or ruin the nature. I think life is just like that.