This document contains only my personal opinions and calls of judgement, and where any comment is made as to the quality of anybody's work, the comment is an opinion, in my judgement.
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Some time ago I bought a third party laptop PSU branded Targus, which is a usually reliable supplier.
The main defect of this PSU is that the interchangeable tip broke off very soon, and for understandable reasons, the main being that electrical contact between main cable and tip is via a 2×pin plug in the main cable and a corresponding socket in the tip.
This is a very good design because it is very convenient and robust and indifferent to rotation. The adaptor tips are a bit bigger, but this is rarely important.
In addition or among the several annoyances
derived from Debian
and its excessively
attitude, I have just discovered that Ubuntu, at least in
version 10, automagically
dynamically discovered block devices (such as USB disks)
This is very inconvenient because once so wrapped the block
devices are therefore
busy and cannot be
reconfigured, for example repartitioned, conveniently.
This is done by a udev script (currently /lib/udev/rules.d/55-dm.rules), and that could be edited or perhaps overridden to avoid this, but a simpler workaround if coarser workaround when one does need to reconfigure a just inserted block device is to run:
This will remove all the active DM wrappings, which usually are only those of the newly inserted device. If more precision is desired, one has to issue multiple commands like:
dmsetup remove /dev/dm/dm0
The Samsung WB2000 camera (also known as TL350 in the USA) has these notable strengths:
MP. The AMOLED is very readable in bright light and from any angle, and the high resolution and big size means that scanning through photos is very pleasant.
Overall a very highly satisfying camera, with some more minor positive points, such as:
The negative points are few and relatively less important:
This camera replaces the previously mentioned Olympus SP-350 (because I had dropped it and cracked its LCD display). I like the new camera rather more than the previous one, which was pretty good, and the main differences are:
To some extent it is remarkable that there are relatively small differences between the 5-year old SP-350 and the WB2000, but the latter is definitely an improvement especially with the new technology for the display and the faster processor.
In summary because of the better image sensors (the lower pixel count helps a lot), the better display and the higher processing speed the WB2000 seems to me significantly better than most similarly priced cameras, and the price is also towards the lower end of the midrange camera segment.
It was interesting to read that Facebook have been having large scalability problems with MySQL:
According to database pioneer Michael Stonebraker, Facebook is operating a huge, complex MySQL implementation equivalent to “a fate worse than death,” and the only way out is “bite the bullet and rewrite everything.”
Not that it’s necessarily Facebook’s fault, though. Stonebraker says the social network’s predicament is all too common among web startups that start small and grow to epic proportions.
Part of the issue is that indeed successful companies grow very fast and getting something to work at all takes precedence over getting it to work well. But part of it is technical, as the main problem unsurprisingly is not so much the size of the databases, but the extremely high degrees of concurrency required:
The is that the site had 1,800 servers dedicated to MySQL and 805 servers dedicated to memcached, although multiple MySQL shards and memcached instances can run on a single server. Facebook even maintains a MySQL at Facebook page dedicated to updating readers on the progress of its extensive work to make the database scale along with the site.
The reason why this is a technical problem is the nature of
the application: on a site like Facebook it is difficult to
exploit locality of data use, as just about any user could in
principle connect to any other user, and
almost certainly involve
driven peaks in resource huge, and un predictable ones.
Relational databases have been designed usually for fairly stable and predictable factual databases typically for registration of transactions and entities, rather than for social networking and online discussions.
In particular MySQL was designed as a simple, even simplistic DBMS for small scale applications, more like the single user Akonadi databases than massively multiuser online social networking sites.
I have upgraded my new laptop some time ago to 4GiB selling out again again to the ever more appalling memory waste of most software, but also because I switched to 64 bit GNU/Linux, which does seem to consume more memory as expected.
I have recently given 2GiB of it to someone else for their laptop as their memory was defective, so I am temporarily back to just 2GiB.
It is way too little. Sometimes my laptop just freezes during paging, in part because of the suboptimal Linux VM and swapping logic. This is mostly because of web browsing, even if having both KDE and GNOME running also impacts, as well as having six virtual screens.
But the main issue is tabs during web browsing, of which I tend to have many because I sort of use them as very active bookmarks. Unfortunately many web browsers implement tabs in a way that requires lots of memory, for example caching previous pages to make the backwards and forward buttons quick. Also web pages tend to be overcomplicated with many gratuitous images and dynamic layouts.
However 4GiB seems still quite monstrous to me for what is after all mostly text work: terminal and EMACS windows, email, and mostly text web pages. Even in 64 bit mode it seems a bit excessive. I can imagine more memory for something like more detailed and appealing games instead, and that has been happening too.