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Spirit 'Will Be Perfect Again' 331
G. Holst writes "NASA technicians are preparing to wipe Spirit's flash memory clean of science and engineering files that have stymied its software. The fix, likely to be made Friday, could completely restore Spirit. "I think it will be perfect again," says the Mission Manager. Chalk this one up for earth!" There are numerous stories about Spirit and Mars: one describes being careful with rm -rf. Reader Tablizer sends in an interesting site: "I discovered Bill Momsen's website where he describes his experiences working on the first successful photographic mission to another planet: Mariner IV to Mars."
flash... (Score:4, Funny)
Flash, a-ha, saviour of the universe
Flash, a-ha, he'll save everyone of us.....
Re:flash... (Score:5, Funny)
perfect again? (Score:4, Funny)
Re:perfect again? (Score:5, Funny)
Re:perfect again? (Score:4, Funny)
Hey Mr. Bush! I didn't know you frequented Slashdot!
Re:perfect again? (Score:5, Funny)
Re:perfect again? (Score:2)
Well the simulation was perfect.
Ctrl-Alt-Del sent to mars... (Score:5, Funny)
Glad to hear Spirit will be feeling herself again.
Re:Ctrl-Alt-Del sent to mars... (Score:5, Funny)
Like that joke.. (Score:5, Funny)
"Goddamnit! There must have been some sudden increase of enthalpy in the cylinder!" the chemist yells, gnashing his teeth, banging on the steering wheel.
"Maybe the fan belt broke or the battery is dead or the wheels came off.." the engineer mumbles.
After thinking a while the computer scientist shrieks in a shrill, frantic voice:
"Let's just try getting out of the car and getting back in!!!@!"
p
Another variant (Score:5, Funny)
The manager says: "First, we have to appoint a committee to investigate the problem and recommend a solution. Then, we must write a project plan, and review the specifications before we can start design and implementation. I estimate it will require about 3 months."
The engineer says: "I have some tools in my briefcase. I can rebuild the master brake cylinder in an hour or so, and we'll be on our way."
The programmer says: "No, no, no! First, we have to push the car up to the top of the hill and see if the brakes fail again!"
My question (Score:5, Interesting)
I mean could VxWorks be responsible for not being able to function with the Flash RAM filled?
Re:My question (Score:2)
Check out this recent Slashdot article [slashdot.org].
Re:My question (Score:5, Informative)
Re:My question (Score:5, Insightful)
Another thing that surprised me is that if the flash had been broken, all data had to be uploaded before the rover went to sleep.. every modern PC can continue to refresh it's DRAM while sleeping. Why can't spirit? Maybe a feature to consider on future missions?
Re:My question (Score:5, Informative)
-B
Re:My question (Score:5, Informative)
VxWorks memory, embedded protection (Score:5, Informative)
Released versions of VxWorks do not have protected memory. (The development version does.) So nothing is there to prevent overwrites by concurrent tasks, etc.
Those of you in the audience experienced in embedded systems know that this makes sense for embedded hardwar -- VxWorks or not -- for three main reasons:
Stuff running in such environments is damn near bug-free. It's not like, say, Mozilla, or even the Linux kernel, or even /bin/ls. These things get tested rigourously, not as an afterthought deligated to the junior programmer.
In systems which are allowed to fail once in a while, reboots are fast. There's no hard drive to spin up, no filesystem to fsck, etc. It can just go *click* and humans won't typically see an interruption in [whatever it was the doohickey was doing].
There's usually no point in memory protection. If the propulsion system walks off the end of a garbage pointer, mission's over. No real use in keeping the guidance system going; it's already on a ballistic uncontrollable arc. If some critical part of the super-smart pacemaker fails (see #1), there's no victory in digging the device out of the corpse and saying, see, this other critical part wasn't affected, thanks to the memory protection! In those cases, memory protection just increases the cost and size of a device, without helping anything.
Protected memory is good for systems which do more than one thing, and/or have parts which can die without killing the whole device (e.g., a desktop computer). And as I said above, some embedded OSes are added such protection for customers who want to adapt their technology to more general-purpose tasks.
Re:VxWorks memory, embedded protection (Score:3, Insightful)
Re:VxWorks memory, embedded protection (Score:3, Informative)
I'd want to see real, hard numbers.
Check out any book on OS design. That's about the typical average cost. The processor's memory manager often has a limited list of memory regions, for example 8 or 16, and this is used as a cache for the active regions that are needed. Whenever the processor attempts to access memory outside those regions, an exception/interrupt is thrown, and then the cache needs to be updated, or an exception thrown
Re:VxWorks memory, embedded protection (Score:5, Insightful)
That's false reasoning.
1. No practical software is bug-free.
2. Testing is never complete.
3. People make mistakes, even during testing.
4. Spirit broke down.
It makes sense, when building a robust system, to do rigorous testing AND have the memory protection.
VxWorks obviously has a brilliant team of brainwashers^Wsalesmen because they've convinced you that you don't need a feature they don't offer. Perfect!
Re:VxWorks memory, embedded protection (Score:3, Insightful)
Absolutely. While building it.
I forgot, this is slashdot, where VxWorks is the eternal enemy, and second-guessing actual rocket scientists is the national sport.
IIRC, memory protection was removed from the early versions by popular request, b
Re:My question (Score:3, Insightful)
Yes modern PCs have all of these wiz bang features but let me ask you this... would you want to be on an airplane where it's fly by wire system was controlled with your PC? No probably not.
Systems that fly and are life critical (yes there is no one on it, but space systems are held to that standard) cannot have a bunch of wiz bang features on board. The more you add, the more potential for failures. So you tr
Re:My question (Score:5, Insightful)
Re:My question (Score:2)
Re:My question (Score:2)
Re:My question (Score:5, Interesting)
files=30
well, that basically told the OS how many files it was going to have to handle at any given time.
Well, in the case of Spirit, it's not that they were short on flash or RAM, it's that the portion of RAM used to handle the files in flash when the flash filesystem is mounted grew unexpectedly for some reason (kinda like the frames in conventional memory you used to access extended memory in DOS). They think the problem was that this portion of RAM used to handle Flash files was not big enough for the amount of files they had in the flash (including files from 6-7 months in transit and a couple of days on the ground in mars).
Soooo, a quick (ok, maybe not so quick) rewrite of the routines in the OS for this flash-files-handling-RAM-portion should do the trick.
Bottom line, it WAS a bug that could only surface with thousands of files in flash, which is something they didn't try on the ground.
Re:My question (Score:5, Insightful)
Which is a reminder to always test the boundary conditions, no matter how ridiculous they may seem. If it is possible to have that many files, then the regression test scripts should generate that many files during testing.
At least it's fixable.
Re:My question (Score:3, Informative)
The problem here isn't so much one of boundary conditions, but of the subtle differences between simulators and reality.
None
Re:My question (Score:5, Insightful)
VXWorks is not that bad (I use it on almost a daily basis). Every single OS has its problems. Before we all go and start calling VXWorks or Spirits software a crappy piece of code, you have to understand what goes into writing space qualified software.
This is not some thing you hack together over the weekend. In fact something you wrote for a space system over the weekend would be tested over a period of months and possibly even years depending on the criticality of the code. We're talking life critical system testing here. That means all paths for you code heads out there.
That said, even when you hit rubber to the road, there are always unexpected situations. Something that you didn't anticipate, a bug that made its way through under circumstance x. Hands up for everyone here who has written a complex bug free system right out of the gates. Anywone who just lifted their hand does not understand what a complex system is or a bug. Though stuff that flies tends to be pretty darn close to bug free.
We are dealing with many complex unknowns when we land something on another planet.
VXWorks is actually very popular with the space program. It's not perfect but neither is Linux (though someday it will be right
Trust me, the software running on the rover is not crappy. In fact, the fact they can bring it back to life like they did says a lot.
The attempt failed (Score:5, Funny)
A press conference is expected tomorrow to announce sending someone to Mars to set the SD cards to allow erasing."
Re:The attempt failed (Score:2)
Flatten and reinstall (Score:3, Funny)
"It's the only way to be sure."
Courageous engineers! (Score:5, Interesting)
Re:Courageous engineers! (Score:2)
They're relieved to just have an option available. Otherwise, it's simply dead.
Re:Courageous engineers! (Score:2)
The excessive consumption of alcoholic beverages does often render that effect.
Re:Courageous engineers! (Score:5, Funny)
Re:Courageous engineers! (Score:5, Funny)
Re:Courageous engineers! (Score:5, Funny)
Re:Courageous engineers! (Score:2)
What?
Yes, I like to live dangerously.
This is all a conspiracy. (Score:5, Funny)
Obviously, this is an attempt to suppress the discovery of alien life on Mars. After a "severe communications fault," NASA is destroying the "scientific" data collected by Spirit. Coincidence? I think not.
I postulate that Echelon (yes, that Echelon) intercepted a message being transmitted by the alien race. Yes, our government subsequently disabled the probe to prevent successful reception!
It's a frickin' lobotomy, man! (Score:4, Funny)
When all else fails... (Score:2)
Normally I would be against just getting out the restore disc and starting over... it usually just causes the problem to come back later.
In this case I think it's a good idea. I'd hate to have to go to Mars to make a housecall on a sick puter
Schernau's Law strikes again (Score:2)
Re:When all else fails... (Score:2)
For me, they'd probably chalk it up as vacation days.
All of 'em, for the rest of my life.
scary (Score:2, Funny)
Early Spring Cleaning? (Score:4, Interesting)
Anyone here know why they bothered to keep the files? Wouldn't they want as much space as possible for the scientific data?
Re:Early Spring Cleaning? (Score:4, Insightful)
Why delete, when you still have room on the flash and you *just* might need that file later...
Of course they then found out that their filesystem handler borks out way before the flash is actually filled up, and that almost bought the whole show to an end... Software QA testing failure in my books, but they seem to be recovering from the fumble pretty well...
Repeat? (Score:5, Insightful)
Re:Repeat? (Score:5, Informative)
I imagine that someone is keeping an eye on it.
Re:Repeat? (Score:2)
Re:Repeat? (Score:2)
I'm disappointed (Score:5, Funny)
Re:I'm disappointed (Score:4, Funny)
Re:I'm disappointed (Score:2, Funny)
NASA: Airplane 2 (Score:2, Funny)
Dave? (Score:5, Funny)
What's happening? (Score:5, Funny)
They've officially lost it.
I think it will be perfect again?? (Score:2)
Re:I think it will be perfect again?? (Score:2)
(flamesuit)
It must be one of those new G5s.
(/flamesuit)
All that porn (Score:3, Funny)
Mars Rover (Score:5, Interesting)
This is truly a wonderful age to live in.
rm -rf !? (Score:2, Funny)
Everyone knows that hardware support in any unix sucks monkey dongs. Hell, these cheap bastards probably installed lunix based on all those 10 year old HOWTOs floating around the web.
On the radio... (Score:5, Funny)
What really happend (Score:5, Funny)
Backup ROM? (Score:2, Insightful)
Re:Backup ROM? (Score:4, Informative)
Obligatory Quote (Score:2)
"Perfect again" (Score:4, Funny)
Easy as Pie (Score:3, Funny)
To restart your Mars Rover, simply insert your NASA Emergency Restore Disc into the CD drive bay located at the side of the Rover. If Autoplay is enabled, the reinstallation software will start automatically. To start the reinstallation process manually, please see the Service Manual included with your Mars Rover OEM package...
Pretty much OT but an interesting question (Score:5, Interesting)
Re:Pretty much OT but an interesting question (Score:3, Informative)
I don't know what the general answer to this question is, but
Re:Pretty much OT but an interesting question (Score:3, Informative)
The U.S. gov't owns them. But, they're probably considered "Abandoned in place" or something.
Related to this topic, I read somewhere that NASA has officially stated that the lunar rover vehicle left on the moon is available for anyone who wants it. At a development cost of over $2mil, it's one of the most expensive cars ever developed. I call shotgun!
Directory Names (Score:4, Funny)
I am rather glad they gave all the directories different names. If they had managed to do otherwise, I would not go so far any more as to call the thing they have a "filesystem".
Might even be a future news: "NASA integrates first non-deterministic filesystem into space probe 'Hope'".
Going around JPL (Score:5, Funny)
"Spirit is willing, but the Flash is weak."
And people wonder why NASA's budget keeps getting cut.
Re:Going around JPL (Score:3, Insightful)
"Watch and pray, that ye enter not into temptation: the spirit indeed is willing, but the flesh is weak."
Sounds like my first IBM clone (Score:4, Funny)
Spirit just needs a good jump start. Anyone got some really long jumper cables?
Obvious reference... (Score:3, Funny)
Flash update you say? I wont enjoy it.
Science and Engineering Files my ass (Score:3, Funny)
Security? (Score:5, Interesting)
If I were a NASA scientist... (Score:3, Interesting)
Each rover uses 256MB flash and so does my 5 megapixel camera. I know for a fact that I can saturate that space fast in a photography frenzy, so I carry a laptop in the car with charger to transfer everything to it if I'll need more pictures.
Altho the two rovers have been a staggering success on Mars, I am surprised at two overlooks:
(1) Keeping track of file size and free space.
(2) What happens if the space is full.
Even Linux on a measly ARM720T does a much better job.
Re:rm -rf?! (Score:5, Funny)
Re:rm -rf?! (Score:3, Informative)
rm -- -rf
Or just use your favorite GUI file manager.
Re:Any theories on what caused the corruption? (Score:5, Interesting)
Re:Any theories on what caused the corruption? (Score:2, Insightful)
Re:Any theories on what caused the corruption? (Score:2, Funny)
Re:Any theories on what caused the corruption? (Score:4, Insightful)
Tim
Re:Any theories on what caused the corruption? (Score:5, Insightful)
On another note, does anyone know exactly what they're deleting here? While I understand that they need to get this mission underway, is there a chance they could lose valuable mission or navigational information?
Re:Any theories on what caused the corruption? (Score:2, Informative)
Re:Any theories on what caused the corruption? (Score:5, Informative)
Re:Any theories on what caused the corruption? (Score:2, Funny)
Should have sprung for the iPod mini instead...
Badum-dum-ching!
Re:Any theories on what caused the corruption? (Score:3, Informative)
Although that is the simple version that most of the press has been relaying, if you've watched the press conferences, the engineers have been carefull to say that they have not been able to fully reproduce the exact same errors on their test rovers here on Earth. The exact cause of the problem really hasn't been determined. And yes, they did stress test the file system before they sent the rovers up and they never saw the type of prob
Re:Any theories on what caused the corruption? (Score:2)
Re:Any theories on what caused the corruption? (Score:3, Interesting)
Re:Any theories on what caused the corruption? (Score:3, Informative)
Not only did it take ~7 months (I think) to get to Mars, meaning it was already 7 months "obsolete" when it landed, it was also probably not launched for a LONG time after it was completed. They have to test it extensively and test for every possible scenario they can come up with. They also have to have equipment that is suitable for the extremes of space tra
Re:Science and Engineering files? (Score:2, Informative)
Re:or fubar it.... (Score:2)
Bad, Bad. stop feeding the trolls...
Re:What Filesystem? (Score:5, Interesting)
Here's the usual rant you see here on slashdot, and it's true: since it was closed source, we couldn't verify that we'd caught all the bad cases, and we couldn't submit the fix to back to WindRiver.
Rock-solid backup policy (Score:2)
I kind of like the idea of "send original hard disk to Mars". This can make it hard to accidentally erase.
Re:Our bench is killing us (Score:3, Insightful)
The reality of the situation is, first string (Russia) is all tied up doing manned missions, so they have delegated the robot probes to the second string (usa). This is mostly due to the little detail, second string has no operational man rated vehicles to work with....
Not quite sure how China plays in yet, but, they also have a manned program these days, so, second place is actually up for grabs, the robot prob