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The final credit granted to all machines which returned the correct result is the same and is the lowest of the values claimed by each machine. The claimed credit by each machine for an identical work unit often varies due to minor differences in floating point arithmetic on different processors. Other users collect large quantities of equipment together at home to create "SETI farms", which typically consist of a number of computers consisting of only a motherboard , CPU , RAM and power supply that are arranged on shelves as diskless workstations running either Linux or old versions of Microsoft Windows "headless" without a monitor.
Like any project of prolonged duration, there are factors that may result in its termination. Some of these are detailed below:. The decreasing operating budget for the observatory has created a shortfall of funds which has not been made up from other sources such as private donors, NASA , other foreign research institutions, nor private non-profit organizations such as SETI home.
However, in the overall longterm views held by many involved with the SETI project, any usable radio telescope could take over from Arecibo, as all the SETI systems are portable and relocatable. When the project launched, there were few alternative ways of donating computer time to research projects. However, there are now many other projects that are competing for such time. In one documented case, an individual was fired for explicitly importing and using the SETI home software on computers used for the U.
To some extent, this may be offset by better connectivity to home machines and increasing performance of home computers, [ citation needed ] especially those with GPUs ,  which have also benefited other distributed computing projects such as Folding Home.
For example, in , Piotr Luszczek a former doctoral student of Jack Dongarra , presented results showing that an iPad 2 matched the historical performance of a Cray-2 the fastest computer in the world in on an embedded LINPACK benchmark.
There is currently no government funding for SETI research, and private funding is always limited. Berkeley Space Science Lab has found ways of working with small budgets, and the project has received donations allowing it to go well beyond its original planned duration, but it still has to compete for limited funds with other SETI projects and other space sciences projects.
A number of individuals and companies made unofficial changes to the distributed part of the software to try to produce faster results, but this compromised the integrity of all the results. BOINC will run on unofficial clients; however, clients that return different and therefore incorrect data are not allowed, so corrupting the result database is avoided. BOINC relies on cross-checking to validate data  but unreliable clients need to be identified, to avoid situations when two of these report the same invalid data and therefore corrupt the database.
The only downside to this is that if the user selects features that their processor s do not support, the chances of bad results and crashes rise significantly. Under SETI home processing loads these experimental technologies can be more challenging than expected, as SETI databases do not have typical accounting and business data or relational structures. The non-traditional database uses often do incur greater processing overheads and risk of database corruption and outright database failure.
Hardware, software and database failures can and do cause dips in project participation. The project has had to shut down several times to change over to new databases capable of handling more massive datasets. Hardware failure has proven to be a substantial source of project shutdowns—as hardware failure is often coupled with database corruption.
From Wikipedia, the free encyclopedia. This article needs to be updated. Please update this article to reflect recent events or newly available information. Retrieved 9 January Tony Phillips May 23, Archived from the original on October 1, Retrieved October 6, Astronomy Picture of the Day.
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University Of California, Berkeley. Discovery of radio evidence of extraterrestrial life. Because we're not done; in fact we haven't mentioned the joint studies; we haven't mentioned the interaction with Santa Teresa. And if we're going to lunch at noon, we only have 40 minutes. We have videotapes that we're going to show you. We'll show you a little snapshot of those just before we go to lunch.
Some of you may have seen little snapshots last night. We have videotapes from the era, from , so you can see what you looked like if you were on tape.
This [begins showing System R slides] was the kind of talk that went around at the time on System R. See - we cover all the bases; everything important is there, right?
Did we miss anything? So of course we have all the people who make more than their manager. We only had one database. Here's "Find the names and salaries of employees who make more than their manager" - right there, number four or something.
Now one of the things I want to talk about is Raymond's discovery of compilation. He gave a talk in the cafeteria conference room in Building 28 once where he said we can compile and it will run faster. I remember that meeting very well because we basically threw out a huge pile of code and started all over again because we realized we were doing it wrong.
And we had to change all our presentations. Like the TODS paper is all wrong, as an example, because we changed the way it worked. Here's an application program. So we just tokenized it and looked for illegal symbols.
There's the same picture as you saw in the overheads. MVS still in parentheses. That dates it, because MVS came out of parentheses in Oh yes, so we load the Why did this project turn into a research project on transactions, and locking, and logging?
Actually the fundamental contributions of the work turns out to be the stuff that hardly appears in the papers, which is all the work that Jim and his colleagues did. First System R install was So here's the definition of all the papers that we wrote. We called it full function, but hardly the full pages that is required today. Oh, here's the "Indian's salary's greater than the chief's salary". Right, you sure didn't. We allowed you to specify a NULL symbol, and then we would insert that wherever it was.
The non-nerds in the room don't even know what we're talking about. If you don't know somebody's age There were great controversies about NULL. Just to give you an example, if you don't know somebody's age, but you know a lot of other things about them and you want to record it in a database but you don't want to put in their age. So you leave it blank, but now you sort, say, on age. Where do you want that person's age to come out: This is NULL theology.
There are the people who want to eat the egg from the big end and people who want to eat it from the little end. And then there are people who want to eat it from the middle. Oh, gee, views and authorization. That's good; didn't know we had all that.
I think I had a big screen for this presentation. I went to accounts payable. Eagle was an IMS successor; it was going to do everything. And they were very worried about path lengths. But TP1 was more of a general characterization; ET1 was a specific program. And then Jim wrote all this stuff down in an article that he published in Datamation. It had Anonymous et al. Actually in about , General Automation beat IMS at the Bank of America for the automated teller system, and we saw the attack of the killer minis that were going to wipe out all the mainframes.
And that was some of the stuff that was driving FS ; some of the stuff that was driving And the benchmark that B of A used was canonized as TP 1, 2, 3, 4, 5, 6, 7. It was called Eagle in one of its many incarnations To call Eagle the same as DB2 is misrepresenting history quite a bit. Eagle wasn't the focus on relational; it was kind of an IMS successor. Oh, I see, it's all the DNA; a tree is the same as a human, right?
With a few changes in the genes. Well, Eagle was a tree. Well, I believe it's possible, likely, that I'm the first person ever to write ET1 in relational. Because I decided we had to have it and everybody else was busy. At that time I was a second-line manager. So I wrote it. And I remember taking some liberties with it. It might well have been Bob Selinger that helped, I mean I know you were working on tracing.
Did you wind up tracing ET1? All right, the details, which we can talk about at lunch, had to do with whether you had to keep the account records sorted by account.
Or whether you can just insert the records into the table and then, at the time you print the bill, sort them then. And I argued for sorting then, because relational doesn't really have a notion of sorting order anyway.
But then there was this argument about whether it was equivalent or not, because IMS was keeping it, if you will, more organized. So what have we got? OK, you get the idea.
There was this presentation that we took everywhere. I have a proceedings of one of the last of the biggies, which was in , at Wang Institute, the Eastern Computer Science Colloquium or something, and Jim and me and Mike Stonebraker and Ted Codd - oh, gee, it's just a long list of neat names Non-procedural, lots of optimization.
This was one of my favorite talks. It talked about how there were many ways to do these things and how you would need an optimizer to make your choice. We had an eight megabyte database! OK, so you get the idea. So I'll put in some of my own reminiscences here for a minute.
At one point, Irv and Frank decided to change the management structure, and in something that I've never seen happen before, Irv worked for me and I became Irv's manager. I spent a lot of time making those slides. And then Leonard was offered a job back working for Bob Evans in New York, and that was onward and upward. He became a director at that point. Frank was named the manager of the Computer Science Department. That left open the job of manager of database systems, which Frank had been, so I took that job.
That was in, like, the end of probably. And I stayed in that job until July of , when my wife was offered a job in Washington DC, and I thought that I should follow her, rather than be left behind and not have a marriage.
So we moved to Washington, and Robin Williams succeeded me in the job of manager of Database Systems. And then the department changed quite a bit; it grew, and it became much more diverse. We were just talking a minute ago about the fact that as System R became more successful, it accreted more.
I remember Don Slutz, for example, was not working on System R in or something. But you joined, what the RDS in? You heard the story about Franco in I mean he was grabbed out of some other thing, and then Don Slutz.
I think that by the time of the end, if you count, I mean Juan Rodriguez-Rosell was a performance analysis guy interested in whatever - operating systems performance - but we converted him into a System R performance person. And so by the time we were done we might have had as much as half the department working on - not necessarily System R, but things related to System R. Mario and Paolo Tiberio were working on a tool to do database design and that was a database design tool that was keyed off System R.
I tell you, my artifact [the CS brochure] is winning. Because during the time I've been talking, it's gotten to the third person, and he's whispering, "Look at this! The joint studies were brilliant in the sense of forcing IBM to move; I'm not sure it was so important for what we learned. Frank had the idea of doing joint studies; actually, I think this was Ralph Gomory 's idea, or Leonard's, or somebody's; Ralph's, I think, as much as anybody. And finally, after about a one-year delay, a major relationship with Boeing Aircraft , in Seattle, Washington.
We have the reports; in fact I have copies of reports and there are copies up there [on the artifact table]. I think Bob Yost brought every single report we got. It's not quite the SQL standard - I mean nothing is that big - but it's a lot of paperwork that was generated. Are you the best person to talk about that? I'm not sure any of these joint studies really exercised all of the neat stuff that we had to offer, like concurrency and transactions and locking and different degrees of consistency and all those different things - they really didn't care about any of that stuff.
The thing that I remembered the most about these joint studies is that we got a lot of trips to beautiful Hartford, Connecticut and Kalamazoo, Michigan, and that was kind of neat. We got factory tours; we got a tour of the jet engine factory in Hartford; we got to go through all the machine shops and watch them building jet engines - that was kind of neat. They told us how at every stage of building the engine they would weigh it very carefully to see if they had left any extra parts inside.
It was a real mess. I remember in particular a wonderful trip to Kalamazoo to visit the Upjohn people. They had a place that they called their homestead, which was a beautiful Victorian mansion on a huge plot of land outside Kalamazoo.
It had a pond and a greenhouse and all sorts of very wonderful accommodations that they kept there for visitors. Tandem bicycles parked around for people to ride around and have a good time. They put us in a room where there was one whole wall completely filled with different kinds of liquor. We asked them if we could take home anything that we didn't drink.
That was a nice trip. A bunch of things were happening at about this time that I think we ought to mention just in passing. And the reason that we had to do that was because of a legal challenge that came from a lawyer.
Mike, you probably can help me out with this. We never found out what kind of an aircraft a SEQUEL was, but they said we couldn't use their name anymore, so we had to figure out what to do about that. So that was how that happened. A couple of other interesting things happened about that time, too. Our famous paper that got published in TODS: And there's a story about that, too. I want to prove something to you by showing you a foil here. If you've ever seen a reference to that paper - that TODS paper - it says the title of it - this is the famous fourteen-author paper; everybody that had ever attended any kind of a System R meeting was included as an author of this paper - so this is the cover page of the manuscript that we sent to TODS for the fourteen-author paper.
If you've ever seen a reference to this paper, its title as it got published was "System R: Relational Approach to Database Management" - it didn't have the "A" in it. When we wrote the paper, it said, "System R: And the reason for that is because when the galley proofs came back from TODS, they sent them back to us for proof-reading, and all of the fourteen authors were alphabetical, and Astrahan of course was first, so a lot of our papers are Astrahan et al.
The penalty that Morton had to pay for that was, he had to proof-read the galleys. So I gave the galleys to Morton, and this was a pretty long paper, he had a lot of proof-reading to do, and he was pretty busy. So he did a pretty good job of proof-reading, but he didn't proof-read the title.
So that's what happened to the "A". Another thing that happened at about that time was that some technical problems came up that got dealt with and solved, and I thought they were kind of interesting and somebody ought to talk about it. I think somebody ought to talk about the Halloween problem. Pat, you had a lot to do with the Halloween problem; do you want to talk about it? I'm having a little trouble remembering this, but we had exercised the "person who earns more than their manager" query to death, and finally got to the point where the optimizer was choosing indexes sometimes to implement this query and it happened to think that the Salary index was a pretty good index to select for this.
And having selected the Salary index for the first time in us testing out the optimizer, we ended up discovering that this query didn't stop. Because we were using the Salary index to go after the Employee table and we were also updating it, and Don Chamberlin kept getting more and more raises. Which made him very happy, but it made us optimizer folks a little bit uncomfortable. So Morton and I sat down and discovered this and analyzed what was going on, and came to one of your RDS meetings and it happened to be on Halloween.
So we ended up telling the group about this and consulting the general wisdom to figure out what in the world we ought to be doing about this thing.
As we talked about it, it came to be known as the Halloween problem. And I think it's still kept that title to this day. It's famous in the industry - everybody knows the Halloween problem.
And it happened to be discovered on Halloween. So that was how the Halloween problem got its name. An interesting footnote is that we just discovered another one of these as sort of a variation on that, in the latest work that we did having to do with referential integrity and things like that, where the referential integrity relationships were going to trigger off the same kind of non-stop behavior.
It's interesting because all these odd-ball things had names: So the phantom was because it was something that was sort of there, but not there; the name was descriptive. And this was called the Halloween problem not because it surprises you, or it's spooky, or trick-or-treat or anything; this is because it happened to be discovered on Halloween day.
But I think most people think it's the other; I think most people think it's called Halloween because it's so surprising. Here are a couple of more artifacts from the joint-study days. I wrote most of the manuals for the users at our various joint studies to use and we designed a nice logo. And Jean Chen helped us make these nice binders that a lot of you still have. When we went to Upjohn, like other places, they gave us a factory tour.
We got a factory tour of Boeing; we got to see them putting together 's and at Upjohn we got to see them making vitamin pills. They would give the vitamin pills away for free in the cafeteria and they all gave us this nice sign. This sign says, "Keep the quality up. Upjohn was the originator of friable pills and that's the heritage of the Upjohn Company, and that was apparently what he said.
You know, Thomas Watson has a lot of famous sayings, you know, "Respect the individual" and stuff. What they say at Upjohn is "Keep the quality up. Gary and Frank Nargi??? At Yorktown , there was a guy named Fred Damerau who was doing natural-language queries. We also had a joint study with a company who was developing some helicopter design based on two-column relations in System R; exclusively two column relations. Do you have any idea when the last System R site went down?
If you used System R, then you came to have it free for a long period after that. So I think they used it for a long time. They were running that on a Model with one megabyte of memory. So in looking back on this, one of the things that I marvel at is the impact that this work had when it was really, by today's standards, very small according to certain measures. And I brought along a couple of foils that kind of show you a measure of things.
This is a profile that I drew up for Frank King one time that shows the number of people that were involved in System R at various stages of its life. From to , this was kind of the profile. We started out at about ten or eleven people. And this was when the Phase Zero prototypes were installed, and this was the different installations of System R at the joint study sites. As you can see, we never had twenty people in System R; probably the average was around fifteen.
And after , it fell off to half that. So the area under that curve was not a lot of manpower by Microsoft standards. But we had a pretty big impact from it. As far as the code size of System R is concerned, believe it or not, it wasn't very big.
Now 38, lines of code isn't a lot; I mean, it's pretty hard to find any kind of a product that small. So add this up, maybe 80, lines of code and that was System R for you.
It's not a lot for what we were able to accomplish with it. This was the size of the load map. That's all there was in the systems that we installed at the joint study sites. So it wasn't very big, either in terms of its code size or the people that wrote it. I kept track of the two lists, called the bug list and the wish list, during the time that we had the joint studies going.
We would have quarterly reports at each of these joint studies and they would wish for things and I would write them on the wish list; we mostly didn't implement any of them. At the end of the project, I think there were something like wishes that were open. The bugs we tried to fix, though, and I've got some statistics on this. This is where the bugs came from. Over the course of the project, we had bug reports.
We found most of them ourselves, but Boeing found a lot, too. These were the number of bugs that were found at different joint study sites. This is what happened to them. So we did our best to Yes, we declared some features. And this was the hero list. This is the people who fixed the most bugs in System R.
The RSS didn't have any bugs. No, it's really true; Franco never wrote a bug. Except for one, right, Bruce? Did you find one? He wrote about half of RSS, and I think we found one bug. And that was after nine years. I remember index management, though, as being a trouble How does the wish list compare with what was implemented afterwards by other systems?
Did you ever look at that? I haven't really looked back and analyzed that. I couldn't tell you about that. Raymond, did you want to talk some more about the compiler and interpreter issue? I don't remember it. It was amazingly short. It didn't stay that short, but short enough to pursue the idea. Now of course, because we started from an interpreter, we went all the way, and compiled into machine language.
Later on, because I think Franco didn't like that, we came back to well prepared tables, rather than code; but of course the idea of compilation remained unchanged, because you do the optimizer once and you package the whole thing; then you invalidate the "code" if things change that impact the access strategy. So that was one of the contributions to the system. It was a good example of how you can change direction in a group and convince people to follow it. It was a good experience. I think that was one of the key things that made System R a success: Raymond's idea to compile rather than interpret our high-level language.
Because that was the thing that was responsible for our performance, and performance was the thing we had to prove to get relational accepted.
Everybody agreed it was sort of neat, but they didn't think it could perform. And Raymond was the man that made it perform. Actually, this is sort of the history. Because they spent so much effort to get it all just right. Let's see, in the TODS era, I gave talks at the TODS era too, and then we had pre-optimized packages - that was some idea that we had that we wouldn't have to go through optimization.
But that was before compilation, correct? Before compilation we were already worried about performance, so we didn't believe that we would fully interpret, but we had this idea of pre-optimized packages, I'm not sure if it was all worked out. It was like you only had to optimize it once, but then you were still interpreting.
Oh, I see it was really like combining the two, doing composition in advance. But then I remember that after Raymond's talk, and we all decided that compiler was it, we had still the question of what to do for ad hoc query. Because Raymond had not proved anything about ad hoc query; he had proven something about canned transactions, that you want to compile canned transactions.
So then the question was, "What about ad hoc query? Then the plan became, "We'll do both an interpreter and a compiler. How are you going to make sure? So then Pat was able to conclude, right, that we could do both ad hoc and canned transactions with the compiler. There were lots of measurements Morton and I were doing on the number of pages touched when doing an ad hoc query.
Once we found 92 pages were hit to save touching two pages at runtime.