These settings control writing back modified pages. The experiments in the paper are read-only. With writes the situation is even worse than shown in the paper (though tuning these settings may help a bit).
This would be exactly the kind of innovation we would need in computer science. Instead we often get stuck in local minima (in this case a 40-year old POSIX interface) without realizing how much pain this causes.
Even after watching these videos and reading lots of articles on the topic, I still find the full C++ memory model extremely hard to understand. However, on x86 there are actually only a couple of things that one needs to understand to write correct lock free code. This is laid out in a blog post: https://databasearchitects.blogspot.com/2020/10/c-concurrenc...
Everyone interested in the history of computing should read The Dream Machine by M. Mitchell Waldrop. The book pretends to be the biography by a little-known, but highly-influential guy named Licklider, but is in fact maybe the best general history of computing. It covers Turing, von Neumann, ARPA, Multics, DARPA (the internet), and Xerox PARC. Alan Key recommends it as the best history of PARC.
Well, the biggest Ivy Bridge EX has 15 cores! There's speculation that the 18 core Haswell-EPs are actually Haswell-EX dies that Intel wants to get rid as fast as possible because these chips have buggy TSX (transactional memory).
But cold caches are an unrealistic assumption. The top-most levels of a tree will always be in cache, unless you almost never access them -- in which case there's no problem either. Additionally, a radix tree is ordered, whereas a hash table is not.
I wonder how long it will take until there is a market for IP addresses. I suspect once such a market is in place IPv6 will not see widespread adoption, since most IPv4 addresses are not really used.
What has happened so far: A curfew was put in place, it has done absolutely nothing, the streets are full of people everywhere in the country. There are reports of dozens of deaths. The headquarter of president Mubaraks party is on fire for hours, no firefighter are there. The headquarter is next the most important Egyptian museums. The police has no control over the streets, the army was ordered in to enforce the curfew. The people are actually cheering as the military is moving in. It is still unclear what the military will do. Hillary Clinton has issued a statement to the Egyptian government to restrain security forces and avoid violence.
The Big Short: Inside the Doomsday Machine is a very good book on the crisis. The Economist calls it "One of the best books on the recent crisis". I very much agree with this assessment. It's written by the former investment banker Michael Lewis who is the author of Liar's Poker and Moneyball.
You visit a family whose three children are all at the local school.
You don't know anything about the sexes of the children. While walking
clumsily round the home, you stumble through one of the three
unlabeled bedroom doors that you know belong, one each, to the three
children, and find that the bedroom contains girlie stuff in
sufficient quantities to convince you that the child who lives in that
bedroom is a girl.
Later, you sneak a look at a letter addressed to the parents, which
reads `From the Headmaster: we are sending this letter to all parents
who have male children at the school to inform them about the
following boyish matters'.
These two sources of evidence establish that at least one of the three
children is a girl, and that at least one of the children is a boy.
What are the probabilities that there are (a) two girls and one boy;
(b) two boys and one girl?
This is actually an interesting variation of the problem. If a random door opens but by chance happens to not have the prize, then the result is different.
Even in England it used to be commonly called Informatics. I like Informatics/Informatik/Informatique etc. much better than "Computer Science", because most applications are not really about computing, but about information.
In order to handle complexity, I split my program carefully into
modules with low coupling. I'm happy until a new feature comes along
which cannot be implemented without destroying the independence of the
existing modules. Then there are two options: Either I redesign the
system based on the new requirements or hack the new feature into the
old architecture. Both alternatives make me sad.
I recognize some repetitive pattern in my code. So I create some
straightforward abstraction that removes the redundancy. I'm happy
until the pattern appears again, but this time in some slightly
different form so that the old abstraction can't handle it. Then I
change the abstraction to include the new case. Eventually, I realize
that the abstraction has only complicated the system, because now one
has to understand both the implementation of the abstraction and the
use of it. This make me sad.
I'm working on some easy task. I know that I have solved problems like
this many times before. Unfortunately this time my brain just refuses
to solve the problem. Without solving the problem, I go home and think
about pursuing a different career.
On the next morning I solve the problem within 5 minutes and I'm glad
to be a programmer.
Interesting. In Russian and Polish this kind of phrase is quite common. In German it's not common, and I would consider it bad style. How about English?
Since nvme0n1 is the EBS boot volume, we have 8 SSDs. And here's the read bandwidth for one of them:
So we should have a total bandwidth of 2.7*8=21 GB/s. Not that great for 2024.