Archive for October, 2006
Filesystems and murder
Hans Reiser created the Reiser4 filesystem which is widely regarded as the best
performing and most extensible modern filesystem. After stumbling upon
href="http://video.google.ca/videoplay?docid=6866770590245111825&q=hans+Reiser">
Hans’ Tech Talk at Google, I was intrigued and
went off to read more about it. You can find plenty of information within the
various links in this post, so I’ll only go over what I personally found
interesting about Hans and his filesystem in approximately chronological
order:
- Hans Reiser was born
in California, dropped out of junior high school because he
didn’t like the way things were taught, and got accepted into UC Berkeley at the
age of 15. He earned a degree in Systematizing (combination of Math,
Physics, etc). -
Worked in
various tech jobs to accumulate capital. Hired a small team of programmers
from Russia (to avoid venture capital) and founded href="http://namesys.com/">Namesys which is responsible for developing the
Reiser filesystem. -
ReiserFS (aka. Reiser3)
was created from scratch by Hans Reiser. Made it into Linux Kernel at version
2.4.1. Hans was dissatisfied with the performance in some key situations (many
small randomly-sized files), so once ReiserFS was stable, he went on to create
Reiser4. -
This would be a good time to read the
href="http://newkerneltrap.osuosl.org/node/5654">interview with Hans Reiser on
KernelTrap. In particular, the Background section where he talks
about the thought process and attitude of being a systems architect, which I
found very insightful. Some of the following points summarize the interview. -
What happened to Reiser1 and Reiser2? Due to a versioning mistake early on,
the major version number got bumped up to Reiser3, and they refused to go back. -
Hans invented an improved data structure for Reiser4 called the
href="http://en.wikipedia.org/wiki/Dancing_tree">Dancing Tree. This tree
structure has better performance than most modern databases (which use
variations of B trees). This has something to do with the tree structure being
more parallel to the way a hard drive stores and reads data. -
Reiser4 code is incredibly modular, clean and well-documented. It boasts an
impressive plugin architecture which supports significant expandability, like
live compression, encryption, metadata, querying, etc. Also, Hans is very
supportive of the open source development mantra and very encouraging of
external contributions. -
Through plugins, Reiser4 is able to match all the functionality that
Microsoft promised with WinFS
and more. -
One example of an impressive plugin is live compression: Due to advancement
in CPUs, we are able to compress data faster than hard drives can write it, so
we can compress things on the fly without performance penalty. In fact, we gain
performance due to the decreased amount of data needed to write or read. More
compression = less space = less blocks to read/write = faster operations. With
average compression rate of 50%, we’d be able to achieve x2 read speeds (as
well as 1/2 storage space required). -
Reiser4’s storage is completely independent of the overlying structure (like
the hierarchical structure that we’re used to). With plugins, Reiser4 can be
extended to function like a relational database or any other metaphor we can
produce. -
Reiser4 is not yet part of the main Linux Kernel branch (but is available
through Andrew Morton’s patchset). Next step is to get it stable enough to make
it into the kernel and then start pumping out those awesome plugins. -
Nancy Reiser, Hans’ wife, disappeared on September 6th, 2006.
href="http://news.google.com/news?q=hans+reiser">Hans was accused
of murdering her. Blood splatter was found. On October 16th, Hans was
arrested. Body still missing. Alternate speculations include that she ran off to
Russia (her place of birth). Great concern for the development of Reiser4
ensues.
It may seem selfish and barbaric to be concerned about the health of the
development of a filesystem when a woman is murdered, but
href="http://www.ninareiser.com/">many people do show compassion.
Similarly, many people believe that Reiser4 is the filesystem,
and with the leaps of advancement it has over competing filesystems, these
people fear for the project’s future. Slashdot discussion covered this topic on
several occasions.
My best wishes go out to Nancy Reiser and the Reiser4 project. May they both
turn out to be alive and healthy.
Bye bye Google
6:43pm - I received my Google Rejection tonight. Google was my ambition for the
past couple of years, but moreso over the past few months than ever befor
e (that’s an understatement). Naturally, I feel disapointment. Yet at the same
time, I feel relief — relief that the journey isn’t over.
Google was my holy grail. If I acquired a job there, I would be content. It
would be over before things even begun. This way, I still have my ambition to
show Flickr, Youtube, Facebook and all those yahoos how it’s done. Hear me roar.
I’ll stop stealing some poor sap’s wireless on Bloor and Huron and drive home.
Good night.
In the UTM cafeteria
Asian guy listening to Eminem on his laptop says: Hey, I’m using a cracked version of Windows, do you know how to get updates?
Me: Nah, sorry. I don’t use Windows.
Him: Oh? What operating system are you using?
Me: Linux
Him: Oh yeah, I’ve heard it’s better… How much is it?
Me: It’s free
Him: Wow, really? So I just go on the Linux website and download it?
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