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BOINC doesn't run multiple projects at the same time. It runs one project at a time, but it divides its time between projects according to percentages that you choose.

There are no active, public projects besides SETI@home yet. Predictor@home is running a public alpha test of its client that anyone can participate in. climateprediction.net began a private alpha test of its client today, and plans to begin a public beta test next month. Folding@home is developing a client, but has not announced any alpha or beta testing for it yet. BOINC Beta Test is still beta testing the BOINC client and may create an Astropulse project based on the client. Einstein@Home may be developing a client based on BOINC for its project which begins in 2005.

I recall reading that some SETI contributors had found ways to artificially raise their rankings for number of packets processed (forget how they did it). This angered some contributors whose high rankings were based on real results, and who were now being knocked from the top spots by the 'cheaters'.

Does the new client include methods to block the methods used to spoof the current SETI@Home client?

From their Getting started covers credits which states the lowest time to completion is what everybody gets for that workunit. Atleast two or more people must crunch the same workunit for this to be a success.

- Benad

Anyway, enough preamble. Here's the problem:
In the Work tab, when I right-click on the currently-running work unit, the context-sensitive menu displays one option, Show Graphics.

When I select Show Graphics, a window pops up, the entire contents of which is black. At this point, my Windows 2000 SP4 computer freezes. CTRL-ALT-DEL doesn't bring up the Windows Security window. CTRL-SHIFT-ESC doesn't bring up the Task Manager. I can't move the mouse. The keyboard is completely unresponsive.

Being a sucker for punishment, I sent a non-maskable interrupt to my CPU, and rebooted the machine. Then I tried the exact same steps, and got the same results. Yup, this bug is repeatable.

So is the new client ready for prime time? Um, not really. Add the insult of the website not recognizing the account ID that it gave me to begin with and I'd say this program should stay in beta a while longer.

A final note: If you happen to be one of the programmers for the client, and know why this problem is happening, reply here. I'd appreciate a reply.

Boinc is more than just an updated Seti@Home, it's a generic delivery platform for distributed projects. That means you, yes you, can develope a BOINC app. Just gather some people to run it for you and compute away without needing any approval from the guys at Berkeley. Basically the participants enter a project URL into the BOINC application, the program then downloads your code and the crunching begins. BOINC handles all the network, workunit, results, distribution, security, versioning etc. issues for you.

Participants can even choose to split their resources among several projects, say, Seti@Home and Folding@Home. Another thing that will also be used in the new Seti@Home is that you can have clients participating in the same project working on completely different computation sets. For example, clients that have proven themselves to have a fast workunit turnaround time and a long history of participating and that have a gigabyte or more of RAM can be given special tasks that would normally be impossible because of the high number of griefers on the net.

I guess this just shows that every project, even a non-commercial one, eventually needs to have someone with some marketing sense if it wants to continue to thrive.

BOINC transparently and securely downloads new application versions. This lets us upgrade and extend SETI@home without requiring you to download and install new software.

The FAQ didn't answer that question--does anyone know?

Will the format of input and output files change?

Yes. The new format is XML-like (though not legal XML).

Added additional science coverage. We now do a thorough search out to a chirp rate of +- 20 Hz/second. The cost of the additional coverage is that clients will take longer to process a workunit

However, as 3.03 is rather old, I wouldn't be surprised if the new and faster computers and old clients that weren't upgraded negated some of the effect.

thng

From page 24: Hidalgo suggests the use of ROC curves, originally from signal detection theory and used extensively in medical testing, as better capturing the important aspects of spam filter performance.

Perhaps a distributed analysis system (similar to SETI@home) could be used to combat spam. Not only could the idle time of bazillions of CPUs be levereaged to improve "signal" analysis, but perhaps the clients could analyize local incoming mail to corelate new trends in spam originators and then share that information with all of the other clients. Then you could combine that with the genetic evolution improvements of the F1 sim-cars recently mentioned on /.

So there's the high-level idea, now you smart people go make it work. :-)

Cause YOU know how much energy each of those weapons would draw compared to a reactor that would fit on the ship?

A fair enough answer. I have to mostly guess at the power requirements due to the exact design being classified, but there is a lower ceiling on how much power these things can use. The laws of physics don't allow you to obtain energy for free. It HAS to come from somewhere.

One gentlemen was kind enough to provide some numbers on energy delivered to a target. 16.9 MJ is tremendous in of itself, and would require the full output of a gas turbine to power. There is a trick however. The poster gave the figure in energy delivered to the target. The actual launch energy must be significantly higher for it to reach its destination. In fact, I wouldn't be surprised if 10x the 16.9 MJ is actually a low figure.

Assuming that it takes 10x the energy for launch, you are now requiring 169 MJ of energy to launch a single projectile. That's one HELL of a lot of energy. Even if we assume that you have several Gas Turbines to cover the energy costs, you still have the issue of fuel. Given that kerosine has an energy density of 36.8 MJ/liter, you'll easily burn through about 4.5 litres of fuel for every launch. (Probably a lot more due to inefficiencies.) That may not seem like much, but once the ship is out of fuel, it can't maneuver and it can't power its weapon systems. In other words, if these ships were nuclear powered, they could stay in a fight much longer (having MONTHS to YEARS worth of power with all systems at maximum draw) instead of bowing out after only an hour or so of fighting.

One of the classical algorithms to do genetic evolution using floating point values (not bits) as parameters, is Differential evolution.

At my school (Berkeley) they're using something by Vernier, most likely this, to require login and password for WLAN access. It's pretty cool--anyone can get a DHCP lease but apparently the Vernier access manager maintains a dynamic routing table that drops all your traffic until you've authenticated. Since they've managed to link the access manager in with the strange Kerberos-ish auth mechanism our school uses ("CalNet") I've a feeling the system is quite flexible and could be easily integrated with class schedules to provide the solution you're looking for. (The literature says it supports all the usual suspects--Kerberos, LDAP, Radius, NT, etc. and those are flexible enough on their own to do it.)

At my school (Berkeley) they're using something by Vernier, most likely this, to require login and password for WLAN access. It's pretty cool--anyone can get a DHCP lease but apparently the Vernier access manager maintains a dynamic routing table that drops all your traffic until you've authenticated. Since they've managed to link the access manager in with the strange Kerberos-ish auth mechanism our school uses ("CalNet") I've a feeling the system is quite flexible and could be easily integrated with class schedules to provide the solution you're looking for. (The literature says it supports all the usual suspects--Kerberos, LDAP, Radius, NT, etc. and those are flexible enough on their own to do it.)

Increasing performance of CPUs and memories will be squandered if not matched by a similar performance increase in BO. While the capacity of Single Large Expensive Disk (SLED) has grown rapidly, the performance improvements of SLED has been modest. Redundant Arrays of Inexpensive Disks (RAID), based on the magnetic disk technology developed for personal computers, offers an attractive alternative to SLED, promising improvements of an order of magnitude in performance-reliability, power consumption, and scalability. This paper introduces five levels of RAIDs, giving their relative cost/performance, and compares RAIDs to an IBM 3380 and a Fugitsu Super Eagle.

From The Case 1107

The central processor was a 36 bit architecture, capable of executing most simple arithmetic instructions in one 4 microsecond cycle time. Multiplication of two 36-bit integers took 12 microseconds, and division of a 72-bit dividend by a 36-bit divisor 31.3 microseconds. The processor performed 36-bit single precision floating point arithmetic in hardware, but did not implement double precision floating point.

From Univac I

The UNIVAC's word size was 72 data bits, which held eleven digits plus a sign, plus one parity bit for each six data bits, giving a total of 84. The mercury delay line memory amounted to 1000 words. Besides numbers, the UNIVAC could represent alphanumeric data (letters of the alphabet and some punctuation marks) using six bits for each character with twelve characters to the word. Codes were assigned for the letters of the alphabet and punctuation marks, such as 010100 for A, 010101 for B, 010110 for C and so on.

According to Why do We need a floating-point arithmetic standard?

Univac 110x float:

Underflow limit = 2^-129 ~ 1.5 x 10^-39
Overflow limit = 2^27 ~ 1.7 x 10^8

What exactly do you think "profoundly gifted" means? That someone can do well on tests?

Psychometricians, neurologists, psychologists... they've been working on what it means for a very long time and what - if anything - the IQ tests actually mean. Working theories cover such things as a larger "cache" (special region of the brain seems to function in the same way as cache on your MB), a greater ability to see consequences of actions, a higher level of raw capacity - some people may simply be able to hold more data, faster recall, greater ability to see patterns (many IQ tests have significant sections on spatial relationships), greater ability to connect abstract bits of data.... the theories are endless.

But what you - and most others - fail to address is that there -are- differences. Look at idiot savants: maybe there is somebody out there who could be brought into a math lab somewhere and tell at a single glance whether a million digit number is prime or not. Maybe there exists somebody who can fold proteins in his head. Maybe everybody thought they were useless morons because they couldn't learn to tie their shoes and they're locked up on Thorazine somewhere.

A high IQ score does not guarantee productivity. A high IQ score -is- a good indicator of -potential-. Kind of like when SETI @ Home sees an interesting signal in the first pass so they'll go back for a closer look.

You may be a genius, but if you want to earn respect from society you've got to do more than just be.

This is a philosophical/ethical/spirital question - should all human life have respect just because it -is- or should we only respect that human life that actually does something? It is also irrelevant to the question at hand. The original poster said "I believe I have these characteristics and I don't know what to do about it". The predominant response was "by telling us that you believe you have these characteristics you demonstrate yourself to be a useless, arrogant schmuck, you horrible loser you, get a life." That horrible zit on the ASCII of society should be encouraged to try and find his limits and act accordingly. Maybe that person will be the one to make an insane connection some day that cures cancer? Or never makes that insane connection because everybody told him to sit down, shut up, and fake interest in people who tell people like him to sit down, shut up and pretend to be interested in others.

And a little bit of my own advice here... This is obvious to most people, but apparently you don't seem to know... When talking about people, phrases like "All muslims..." are never going to be accurate. You can't lump billions of people into the same category. What if I say, all Catholic priests are pedeophiles? The actions of a few, or even a majority, don't speak for the actions of an entire group. It just doesn't work that way.

Also I think you should relax and take comfort in the fact that everything happening on this planet is, in persepective, quite trivial.

A little Googling found fixdisktable. Link 1 and 2.

Good luck.

A little Googling found fixdisktable. Link 1 and 2.

Good luck.

Berkeley Groks has an interview that aired today with John Derbyshire discussing the Riemann Hypothesis. He states that after talking with many mathematicians in the field, the prospects for a solution any time soon are quite low.

A quick example -- Microsoft doesn't implement IETF standard TSIG in their DNS implementation. So, your DDNS options are:

3. Use non-MS DNS and TSIG from workstations -- MS systems can't use DDNS

Which DNS service exactly are you using? I know BIND definetely works with Windows 2000 AD - at least Berkeley seem to have gotten it working.

What you are suggesting is effectively a capability based os like EROS. Now, the trouble indeed with current mainstream systems is that even when apps DON'T run as the root user, the actual normal user has way to many priviledges to give to their programs. The trouble is, in a mainstream OS it's damn near impossible to NOT let your program have all the priviledges your user account has. Capabilities are by no means a new idea, and one need not make system less usable to have them. Building an easy-to-use capability system that functions well and does everything that users expect it to do, requires quite a bit thinking and design though.

Just my .02 euro.

Pine was written at UC Berkeley and does indeed stand for "Pine Is Not an Editor."

The dark energy refered to is unusual because it implies a kind of antigravity. It isn't drawn into play to account for the fact that the universe is expanding, but rather to explain the recent observations that indicate that the rate of expansion is increasing.

It is related to Einstein's cosmological constant which Einstein regretted introducing because it was kind of a kludge to account for a supposed static universe.

Apparently there are cosmologists today who still regard it as a bit of a kludge, making the cosmological model convoluted like Ptolemy's model of the solar system. There was a recent Scientific American article that discussed this, but only a summary is available online.

Maybe you were confusing it with dark matter?

Here is a good link to a study on WEP.

(In)Security of the WEP algorithm

What people fail to realize is that there are some flaws with WEP that make it easy enough to decipher. If you simply don't want someone to see what is in your data packets floating over the airwaves, setup a VPN connection to a wired station from your mobile devices.

You should also consider turning on MAC table filters to prevent unwanted cards on your network. This isn't fool proof because of MAC address spoofing, but its a start.

Once WPA and some other other improvements being talked about come out, things might improve a bit, but that really is the game. People that want data find ways to get it and that includes cracking codes. *Notes other article about Lorenz on /.*

The Fall of Colossus (Forbin enlists aliens to take Colossus down)

Colossus and the Crab (they rebuild it)

If you happen to be in Berkeley, CA, go to the top of the hill above the campus and visit the Lawrence Hall of Science, where the exteriors for Colossus were shot. There's a great view of San Francisco Bay from there. (LHoS is pretty cool, too.)

Unsecured WiFi networks all over the country are very useful to criminals and terrorists.

I'm also rather shocked that DHL hasn't noticed this either. Open WiFi networks are pretty anonymous. The Access Point may log the MAC address of the NIC, but that address can be easily changed on most cards.

Not to mention that WEP isn't very secure. Once someone cracks the WEP key, they can probably figure out the MAC address for the other computers on the system, and mimic one of those systems.

So, the Feds can track the traffic down to the Access Point, and then they can find out the MAC address. By then, the evil individual is long gone, and has wiped the MAC address from their system.

One major flaw I see in telling people to enable WEP on their WiFi is the first question I'm sure to get back is "How do I do that?

So what? It's not like WEP provides security. It's a fundamentally broken protocol.

CNN is engaging in dangerous misreporting. They spun it so that insecurity is the AP vendors' fault by making WEP difficult to activate. This will lead viewers to believe that once they manage to enable WEP, they're safe. And that's just absolutely wrong. You'd be safer with no WEP and higher-level encryption (although running secure application protocols is even further outside the imagination of typical consumers).

People who made changes to the source code tended to want to have their names added to the acknowledgement. With large numbers of people working on a single project (or for many separate projects in a software distribution), the advertising clause quickly created large and unwieldy acknowledgements. Another practical problem was legal incompatibility with the terms of the GNU General Public License (which does not allow the addition of restrictions beyond those it already imposes), forcing a segregation of GNU and BSD software.

On July 22, 1999, William Hoskins, the director of the office of technology licensing for Berkeley, revoked the clause. The document enacting that revocation is available at ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.Lic ense.Change

It's a fascinating handdrawn design app, that might be appealing to non-programmers.

Here it is

Berkeley Logo looks like a very nice implementation (thanks Google). You can grab it gratis for Windows, Linux. Mac, DOS from this guy's home page.

Thanks for asking - you've inspired me to download it.

Just a theory? You're right! However, you're also very, very wrong.

Just a theory? You're right! However, you're also very, very wrong.

Just a theory? You're right! However, you're also very, very wrong.

Bacteria exchange genetic material.

Viruses mediate the exchange of genetic material.

The development pathway that unites all animals includes a stage in which a viable (usually fertilised) egg cell (zygote) divides a number of times to form a ball of cells (morula, blastula) gradually differentiating because of (dorsal/ventral etc.) gradients in (HOX) gene expression.

Sponges (porifera) are a likely candidate for the oldest surviving animal lineage, potentially dating from the recently annointed Ediacaran Epoch through the Cambrian explosion, so called because the basic developmental forms of animals diversified wildly in a (geologically) short time.

Hermaphroditic sponges produce sperm and eggs at different times, obviating themselves, and thus the last common ancestor of all sexually reproducing animals, from any requirement for different male and female phenotypes.

Sexual dimorphism came later and very differently in different taxa.

Such "all or nothing" questions are a standard intellectual trap for people who cannot see the overwhelming evidence for the fact of evolution, a fact that various theories strive to account for without ever needing to overturn the core Darwinian insight that everything alive today is the product of a very long history of variation and selection from multitudinous common ancestors.

The extinction event killed off all species larger than about 20kg. That wouldn't have included any mammals. Mammals 65 million years ago were tiny (mice sized) and most likely nocturnal.

The extinction event killed off all species larger than about 20kg. That wouldn't have included any mammals. Mammals 65 million years ago were tiny (mice sized) and most likely nocturnal.

Some key benefits to the idea of letting one person drive a gaggle of cars are

1. You can design the cars to densely tailgate each other to take advantage of slipstreaming. That buys you significant gains in gas mileage since most of a car's power at highway speeds is spent just moving air out of the way.
2. Cars can move at much higher speeds since human reaction times are removed from the chain. Right now, if you're in a line 100 cars long, it takes at least 50 seconds from the time the first car in line moves before the 100th car gets moving. With this technology, when the first car moves, all the cars move. When the first car stops, all the cars stop.
3. It allows for self-assembling trains. Fixed rail is well, fixed. Cars go wherever anyone wants to go when they want to go. By allowing one person to drive, and everyone else to follow, you'll have long strings of cars (just like you have train cars) that can peel off when they wish and can join when they wish. You get most of the efficiency of trains without having to coerce people into living in certain areas or travel to certain destinations.

And Microsoft could build software into its desktop version of Windows to harness the power of PCs, letting companies get more value from their computers. It's a technology that's applicable to tasks such as drug discovery and microchip design.

sounds a lot like seti@home, folding@home, or the grid project. Another example of embrace and extend. It's definitely going to be interesting when pc's are networked for spare cpu cycles as a normal everyday event. Maybe the can use all that cpu power to get some AI to rewrite windows code so its bulletproof.

to get back on the cool side, i've been a longtime seti@home participant...

lothar97 stats

:-P

Here's the official explanation from http://setiathome.ssl.berkeley.edu/about_seti/radi o_search_2.html:
Nature provides an even nicer way to further refine our frequency range. The simplest "stuff" of the universe, neutral hydrogen gas in interstellar space, emits radio signals at 1.42 GHz. Another molecule in space, the hydroxyl, or OH, emits at about 1.64 GHz. Now if you look at these two, H and OH, you would see that together they make up the compound of water HOH (or more commonly H2O). Life as we know it requires water to evolve and exist. The frequency range between these two emissions, from 1.42 to 1.64 GHz, is therefore a quiet region of the spectrum called "the water hole."

1 server processes spam, 1 processes viruses, 1 is a DNS server. The other 17 process data for the SETI@home German team.

When I saw this on slashdot, I thought that I had been doing SETI@Home for much longer than that, but apparently I registered May 16th, 1999, early in the UTC. Their news release puts the anniversay as May 17th.

Not sure if you have realized this by now, or if its even still applicable with the newer versions of SETI@Home, but when I was running it on my old PC, I found process time/unit was cut in half if I turned off the graphical screen saver.

In screensaver mode, SETI@home runs fastest if the screen is blanked, so for maximum speed set the preferences to blank the screen after a short time. FAQ

I'm not sure how they decided the official start date. They have users who signed up as early as March 1, 1999.

The true birthday was May 17th, per a post on the SETI home page dated May 18th indicating that "SETI@home turned five years old yesterday"

It's called BOINC (Berkeley Open Infrastructure for Network Computing), and it's still in beta, but progressing. I have it on one of my systems, but it's only working on one project right now. Aside from the occasional software update, I've not touched it in a month or two, so I'm not sure if they've implemented any more projects.

Finally, note that on modern drives, you can seek all the way across the disk in only about 30-50% more time than you can seek a short seek. Thus keeping your blocks close to the current cylinder but not in it has very limited value. Note that this is not the case on optical (CD/DVD) disks.

Bzzt. Wrong. Thanks for playing.

Seagate Barracuda 7200.7 Plus product manual. This is a modern drive. Look at page 17 of the PDF, section 2.7, "Seek Time". Track to track seek is listed as sub 1ms, while average seek is 8.5ms (for read). Latency (the rotational aspect), which is separate, is an average of 4.16 (as it should be for a 7200 RPM drive). So a short seek is 8 times faster than an average seek, much less a whole-drive seek. So keeping your blocks close to the current cylinder but not in it still has high value.

Additionally, if you can keep your data in the same track, you don't have any seek time, just rotational latency. And the size of track groups has been growing as densities have been growing. So there are lots and lots of blocks in the same track that aren't within readahead range.

And fragmentation is not a bugaboo. It's a fact. When you have random allocation on a volume, it will get fragmented.

Now you misuse the term "random allocation". When talking about disk, random allocation means that you randomly choose your next block--which certainly will cause fragmentation. I think what you are looking for is random file creation. However, under FFS, if you maintain sufficient free space, it is very unlikely that real fragmentation will occur even with random file creation/deletion. Yes, you won't be able to store all of your files contiguously. But as the grandparent points out, the old FFS block allocator finds "nearly optimal" blocks. From the original paper on FFS, you don't get serious fragmentation-related performance issues until you reach 90% disk utilization (there's an '86 FFS paper I can't find an electronic copy of which does a better analysis, but even the '84 paper has the 90% figure). At 90% utilization, nearly every file system ever starts getting severe performance problems due to fragmentation.

You can go back after the fact and unfragment it, but doing so in any serious fashion when writing files actually degrades performance due to the extra effort required.

You should read about log-structured file systems sometime. Like Sprite. The base idea of a log-structured file system (LFS) is that you don't try to keep your blocks the same. You write a log of changes, and stream that out continuously to make maximum use of your available write bandwidth. This has the severe downside of causing horrific freespace fragmentation, since every change to a file means the affected blocks are reallocated, and the old blocks are now garbage. So you have continuous freespace compaction (called segment cleaning in the paper). LFSs didn't catch on because at the time, they needed a large amount of free space compared to more traditional "overwrite" file systems to maintain performance. However, recent work with log file systems shows that the changing performance characteristics of disks (much higher bandwidth but same seek/rotational delays) have tipped the balance to log structuring. Regardless, the cleaning process is precisely going back and unfragmenting your data, and is necessary for a LFS.

HFS+ does nothing to prevent fragmentation except for use super-clusters.

As pointed out by others, Apple's later implementations do defragmentation of smaller files when they are accessed.

NTFS could do this, but I believe they do not. However, NTFS on servers has an allocation block size of 8K

People interested in this should also check out Eiffel and Sather as well.