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Reformatting a Machine 125 Million Miles Away

Soulskill posted about three weeks ago | from the red-rover-red-rover-send-updates-right-over dept.

Mars 155

An anonymous reader writes: NASA's Opportunity rover has been rolling around the surface of Mars for over 10 years. It's still performing scientific observations, but the mission team has been dealing with a problem: the rover keeps rebooting. It's happened a dozen times this month, and the process is a bit more involved than rebooting a typical computer. It takes a day or two to get back into operation every time. To try and fix this, the Opportunity team is planning a tricky operation: reformatting the flash memory from 125 million miles away. "Preparations include downloading to Earth all useful data remaining in the flash memory and switching the rover to an operating mode that does not use flash memory. Also, the team is restructuring the rover's communication sessions to use a slower data rate, which may add resilience in case of a reset during these preparations." The team suspects some of the flash memory cells are simply wearing out. The reformat operation is scheduled for some time in September.

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Hey, Bob, this is Jim (5, Funny)

Anonymous Coward | about three weeks ago | (#47790999)

We're gonna need you to go out to the rover and reboot it. Yeah, it got stuck. You should probably leave ASAP.

Deploy the Paperclip! (1)

apraetor (248989) | about two weeks ago | (#47792887)

I'm picturing something akin to those Shuttle missions to repair flaws in the Hubble telescope's optics, except involving a NASA-engineered paperclip.

Simple fix (2)

SternisheFan (2529412) | about three weeks ago | (#47791007)

Easy, just gotta' replace the button battery.

Re:Simple fix (2)

sillybilly (668960) | about three weeks ago | (#47791353)

It's running on solar power, that's how it lasts 10 years. Though the rechargeable battery must be tough to take so many recarchings.

Ideally, you have redundant systems for such a situation, where you can take one of them down and use the other to do the booting, formatting, programming, as if there were a user sitting right next to it. They say it has a flashless mode of operation, but the way I think of it, as in a regular PC, with a BIOS, you can reformat the harddrive without booting off of and using the harddrive, such as booting from a floppy, or even ROM chip they used to have back in the 80's (ROM-DOS 3.3 or ROM BASIC). So when flashing a BIOS or a ROM chip, there is no lower level to boot from, but if you have Tandem, dual redundant systems for everything, you can boot from the lowest of lowest levels and have the partner system execute all the commands. So with Tandem failure is less frequent, as in, you're down to 50% capacity but still fully functioning ok, and can work on regaining the 100% capacity, while not using regular operations, for two days and the like. The problem with Tandem is the double or higher cost, and, in space missions, the extra power consumption and extra weight, and in space missions, weight is almost everything, as each lb has to be paid for dearly, on the order of $10,000/lb low Earth orbit, and who knows how many gazillion dollars per lb for a Mars mission.
There used to be a company named Tandem, designing dual CPU redundant resilient failure tolerant systems, but they fell behind on chip design because of small size, plus high expense, and did not compete well in the computing field. For instance back in 1999 when Google started, they started with regular pc's of whateve the vogue of the day was, I don't know, 700 MHz PIII, maybe? And just jerry rigged a bunch of them into a daisy chain and voila, you have a Tandem-like, more than dual, more like thousandfold or millionfold duplicated, resilient supercomputer. But the principle of tandemness and fault tolerance was there. Maybe for space missions that need fault tolerance like that, it may be worth the extra rocket fuel weight in the first place to double the weight and duplicate most critical systems. The human body duplicates kidneys, lungs, but not liver, or heart, so there is a balance on what you want to go redundant on and what not. Life is easy with 2 kidneys, some people can live with only one kidney, but it's really difficult to live with zero kidneys.

Re:Simple fix (1)

Anonymous Coward | about three weeks ago | (#47791381)

Wow. Talk about missing an obvious joke and over-thinking the response. Seriously epic *WHOOSH*

Re: Simple fix (2, Funny)

Anonymous Coward | about three weeks ago | (#47791573)

Ass-burgers.

Re:Simple fix (2)

davester666 (731373) | about three weeks ago | (#47791911)

what's this step 4??

Press the reset button.

Who the hell designed this stuff?

And I thought I was cool... (1)

toygeek (473120) | about three weeks ago | (#47791015)

When I reboot machines in Asia or UK/EU using IPMI from the US.

Re:And I thought I was cool... (4, Funny)

marcello_dl (667940) | about three weeks ago | (#47791039)

And I thought I was cool when I reboot servers around the world thinking I am rebooting mine.

Err, if you're a system admin.. (4, Funny)

Viol8 (599362) | about three weeks ago | (#47791181)

... you're not cool. Period. Sorry.

Re:Err, if you're a system admin.. (1)

Anonymous Coward | about three weeks ago | (#47791231)

Everybody is a system admin when linux is involved, and I like it that way. But I digress.
alias halt='echo Use shutdown instead'
alias reboot='echo Use shutdown instead'

Re:Err, if you're a system admin.. (0)

Anonymous Coward | about three weeks ago | (#47791305)

alias halt='echo "Use shutdown instead"'
alias reboot='echo "Use shutdown instead"'

FTFY

Re: Err, if you're a system admin.. (0)

Anonymous Coward | about three weeks ago | (#47791663)

Shell noob. echo doesn't need its arguments quoted unless one of those arguments might expand because of shell globbing and you don't want that globbing to occur. In this simple case of fixed strings definitely not.

Re: Err, if you're a system admin.. (0)

Anonymous Coward | about three weeks ago | (#47791917)

Not just globbing -- also string splitting (and unless you know IFS, you don't know what an expansion will split on). Granted, not the case here, but good practices are good practices.

Err, if you're a system admin.. (0)

Anonymous Coward | about three weeks ago | (#47791311)

Jokes about irrelevant characteristics aren't funny. Period.

Re:Err, if you're a system admin.. (1)

Anonymous Coward | about three weeks ago | (#47791433)

Typing out "Period" makes you look retarded.

Re:Err, if you're a system admin.. (-1)

Anonymous Coward | about three weeks ago | (#47791499)

Repeatedly emphasizing a lie by ending it with the word "Period" sure made Obozo look retarded. Well, to everyone but the Flavor Aid drinkers.

Re:Err, if you're a system admin.. (1)

marcello_dl (667940) | about two weeks ago | (#47792575)

Err, if taking a server offline, no matter the reason, is a serious problem, then you are not a good - or properly funded - sysadmin.

If there is a problem and need to call "support" (1)

Anonymous Coward | about three weeks ago | (#47791029)

do they get sombody in or from India?

Re:If there is a problem and need to call "support (2)

sillybilly (668960) | about three weeks ago | (#47791361)

I'll be glad to help you with that Sir.

Re:If there is a problem and need to call "support (0)

Noah Haders (3621429) | about two weeks ago | (#47792191)

A tech support guy from India helped me with my licensing problem. He was very nice and efficient and solved it right away. No complaints.

Send someone (1)

TheDarkMaster (1292526) | about three weeks ago | (#47791043)

With a replacement SLC SSD and a screwdriver

ECC? (5, Funny)

TechyImmigrant (175943) | about three weeks ago | (#47791059)

They didn't do any ECC on the flash memory? I thought these people were rocket scientists.

Re:ECC? (-1)

Anonymous Coward | about three weeks ago | (#47791097)

I know you're a dumbass.

Re:ECC? (0)

TechyImmigrant (175943) | about three weeks ago | (#47791809)

If you're so smart, why aren't you advocating using BCH codes or Reed Solomon codes or some form of forward error correction code over code and data stored in flash so random bit errors in flash won't affect the code that is stored in the flash? What is your super clever alternative?
 

Re:ECC? (4, Insightful)

Nimey (114278) | about three weeks ago | (#47791869)

You're a poster child for Dunning-Kruger [wikipedia.org] : some random on the Internet who thinks he's smarter than the folks who designed a Mars rover that lasted over 10 years past its 90-day expected life.

Re:ECC? (1)

DMUTPeregrine (612791) | about three weeks ago | (#47792033)

There's also the matter that better ECCs cost more overhead. You can detect single bit errors with a simple parity bit, but double errors will go undetected. And even something like Reed-Solomon can't correct all the errors it can detect. Spacecraft going to mars have very limited mass budgets, there are often better places to spend the extra mass than on an additional redundant flash chip (and associated circuitry).

Re:ECC? (1)

Noah Haders (3621429) | about two weeks ago | (#47792197)

They clearly overspecced it. Maybe if had been designed more reasonably they could have sent more.

Re:ECC? (0)

Anonymous Coward | about two weeks ago | (#47792659)

Yeah, they over-engineered the thing by at least a factor of 40. Clearly they were geniuses.

Re:ECC? (0)

Anonymous Coward | about three weeks ago | (#47791155)

In space, no one can hear you trolling.

Re:ECC? (3, Insightful)

Anonymous Coward | about three weeks ago | (#47791193)

As it happens, for flash, read errors are often transient. A better model than DRAM style ECC is to treat it more like a disk drive with checksums on each block. If you get an error, reread the block. And if you have a problem writing a block (e.g. the readback is wrong), just use a new block. Surely you've noticed that your USB thumbdrive gradually gets smaller with time as blocks wear out. (In space hardware, back in 2000, wear leveling was done manually.. still is as far as I know.. there's no nice rad-hard flash controller chips to make a big pile of MLC flash look like a disk drive, etc.)

The long duration radiation performance of flash memory (particularly back in 2000, when these things were being designed) was/is not particularly well understood. There are a lot of what is called Enhanced Low Dose Radiation Effects (ELDREs) that are poorly understood for all semiconductor devices: you can't just blast the part in an accelerator at 1kRad/hr for a few days to get to a few hundred kRad and expect that this is the same as taking a few tens of Rad/hr over days and days and days, with 12 hours off after the sun goes down to anneal and heal.

And, because resources on spacecraft are very precious, one doesn't blindly head off and say "let's just TMR everything". You make a rational choice based on the expected design life and the data you do have and pray for the best.

And, of course, the design life was 3-6 months, and here we are 10 years later, still cranking along. I think it's done pretty well, all things considered.

Re: ECC? (0)

Anonymous Coward | about three weeks ago | (#47791273)

ELDRS actually stands for "enhanced low dose rate sensitivity", and it's normally simulated using a Co-60 gamma source, not a particle accelerator. It's primarily a concern for bipolar devices, not MOS devices like flash memory, although radiation effects in general are difficult to predict.

Re:ECC? (2)

Anonymous Coward | about three weeks ago | (#47791219)

The rocket scientists did their job ten years ago. They're working at McDonalds now.

Re:ECC? (0)

Anonymous Coward | about three weeks ago | (#47791307)

This is the most important post in the discussion.

Re: ECC? (1)

Anonymous Coward | about three weeks ago | (#47791711)

This would make an interesting movie plot where they have to recall all the older, laid off rocket scientists working at McDonald's and bagging groceries at the supermarket to reboot an idle probe on a far away planet because it's the only one that can be repurposed to save the earth from an asteroid impact. But only the old guys know the hardware and can reprogram the firmware.

Yeah I'm a laid off old guy. Get off my lawn!

Re: ECC? (1)

rickb928 (945187) | about three weeks ago | (#47791799)

And add in the volunteer group that decided to save the project, working out of an abandoned McDonald's.

Oh, wait....

Re: ECC? (0)

Anonymous Coward | about two weeks ago | (#47792647)

This sounds like what Deep Impact should've been.

Re:ECC? (0)

Anonymous Coward | about three weeks ago | (#47791277)

They didn't do any ECC on the flash memory? I thought these people were rocket scientists.
Rocket scientists *on a limited budget*. ... another version of the same:
I guess the question I'm asked the most often is: "When you were sitting in that capsule listening to the count-down, how did you feel?" Well, the answer to that one is easy. I felt exactly how you would feel if you were getting ready to launch and knew you were sitting on top of two million parts -- all built by the lowest bidder on a government contract. -John Glenn talking about his early days at NASA preparing for lift off in Friendship 7

Re:ECC? (2)

schlachter (862210) | about three weeks ago | (#47791489)

Well, in their defense, ECC on the flash memory isn't exactly rocket science.

Re:ECC? (0)

Anonymous Coward | about three weeks ago | (#47791899)

Even with error correction, there will be undetected errors and unrecoverable errors. Obviously, the degenerate case is where the drive isn't functional - no amount of error correction can help you. Mars is a high-radiation environment, so these drives have probably seen a fair amount of abuse.

My guess is that they *do* use error correction (after all, even consumer flash drives use ECC), and that the high-radiation environment and normal wear-and-tear are simply causing the flash drives to start failing.

Re:ECC? (0)

Anonymous Coward | about two weeks ago | (#47792291)

They didn't do any ECC on the flash memory? I thought these people were rocket scientists.

NASA laid-off the rocket scientists replacing them with astroturfers as a cost-saving measure. HR thought the astroturfers could double as landscapers for future colonies.

Remote management (0)

Anonymous Coward | about three weeks ago | (#47791061)

Not that's a serious remote management of system :P

Just wondering if flash memory cells are dying, they need to comeup some way to go arround those...

Re:Remote management (5, Informative)

ledow (319597) | about three weeks ago | (#47791151)

Not really...

The chances are that "reformat" isn't what we think and includes one of more of:

1) Rewriting cells and allowing wear-levelling and sector-replacement to take place, and make bad sectors as bad.
2) Write-testing and manually avoiding those sectors that don't perform as expected.
3) Rewriting all the critical storage functions to avoid the already-known bad sectors.

It's the kind of thing that anyone can play with. Not saying it's not risky on a remote device, but BadRAM etc. patches have been in places for years and that's a way to run Linux on machines with faulty ***RAM****, not just long-term storage.

Many years ago, a bad sector on your hard drive was something you found out with scandisk (or previous tools) and then it was marked as bad and that was the end of that. Your PC wouldn't use it and so long as it wasn't the boot sector, that was the end of that. It was only the "creeping" bad sectors, where you got more bad sectors over time, that would really worry anyone.

I imagine that it's not at all difficult to make sure that multiple boot sectors were in place if you really wanted to but why bother? The chances are billions to one. Chances are this hardware has MUCH better fault tolerance and multiple hardware watchdogs, firmware, and boot attempts to make sure it eventually gets back up SOMEHOW.

There's a reason that even FAT stores two copies of the allocation table, why Linux ext filesystems store multiple copies of the superblock, etc. They come from a legacy where the occasional bad sector wasn't a problem and where 20Mb of hard drive cost more than the computer did so it was better to cope with the fault than just tell people to buy a new one. And their predecessors were (and still are) mainframes with hardware that's just that fault-tolerant in the first place anyway.

It's not at all hard to write a filesystem that can cope with not only damage, but even recurring damage. You've seen PAR files presumably? The same could easily be done on a filesystem-level basis (and I imagine, somewhere, already is for some specialist niche).

It's not that big a deal once they KNOW that's the problem. The biggest problem is that they only "suspect" that's the problem.

Re:Remote management (1)

pegdhcp (1158827) | about three weeks ago | (#47791279)

Ultrix used to mark bad sectors on the fly, as far as I could remember, if the disk was not a SCSI...

Re: Remote management (0)

Anonymous Coward | about three weeks ago | (#47791805)

Only the earliest MFM disks needed the OS to mark bad sectors because there was no intelligence in the disk controller. As you said. .. if not SCSI. Modern ATA and SATA controllers will mark bad blocks on each write and remap the bad area so the OS never knows. Blocks that degrade over time or get damaged at power on/off are the troublesome ones and are only found when one day you can read those blocks any more.

So scrub your disks weekly to find these blocks early.

I always thought that the disk controller should do idle scrubbing. Are there any modern SATA disks that do this?

Re:Remote management (1)

lgw (121541) | about two weeks ago | (#47792039)

You've seen PAR files presumably? The same could easily be done on a filesystem-level basis (and I imagine, somewhere, already is for some specialist niche).

While all hard drives now do their own Hamming error correction (or something better), RAID2 is the same idea for "raw" storage that doesn't: you write explicit ECCs to redundant volumes to allow recovery from both drive loss and bad sectors.

RAID5 with modern drives gives all the same resiliency, as the drives do the block-level ECC themselves, so you never see RAID2. But for a pile of flash memory, that's the filesystem-level equivalent of PAR files.

Alternative Title (4, Insightful)

wisnoskij (1206448) | about three weeks ago | (#47791067)

How to brick a 2.5 billion dollar device.

Re:Alternative Title (1)

TapeCutter (624760) | about three weeks ago | (#47791093)

Not sure if it was opportunity or its twin, but one of them required a modem reset not long after landing.

Re:Alternative Title (5, Interesting)

Zarhan (415465) | about three weeks ago | (#47791595)

Not modem reset. The filesystem on Spirit had bunch of temp files and other stuff from the Earth-Mars flight, and apparently it just ran out of inodes. So basically they had to remote into whatever constitutes a bootloader with 20 mins of latency and remove some of the no-longer-needed files.

See http://science.slashdot.org/st... [slashdot.org]

Re:Alternative Title (0)

Anonymous Coward | about three weeks ago | (#47791147)

Can't tell if trolling or just stupid.

Re:Alternative Title (1)

Nimey (114278) | about three weeks ago | (#47791885)

Never attribute to malice that which is adequately explained by stupidity.

Re:Alternative Title (3, Insightful)

rasmusbr (2186518) | about three weeks ago | (#47791167)

I would imagine that the system probably boots itself off of a ROM chip that has a routine for receiving data from Earth and storing it in RAM and then flashing that data onto the flash chip.

If the rover does not boot from ROM then it is a miracle that it hasn't bricked itself yet.

2.5 billion? (1)

Viol8 (599362) | about three weeks ago | (#47791191)

I dunno so much these days. Its 10 years old and got a few miles on the clock plus collection for the new owner would be an issue. On the plus side vandalism won't be a worry. For a few centuries anyway.

Alternative Title (2)

Whiternoise (1408981) | about three weeks ago | (#47791225)

They will almost certainly do a dummy run on an identical piece of flight hardware on Earth. The only difference is how the data are sent.

Re:Alternative Title (1)

wisnoskij (1206448) | about three weeks ago | (#47791495)

And the state of the hardware. Some unknown number of systems on the real curiosity are degraded to the point of malfunctioning; And they have little to no way of exactly measuring what and where.

Re:Alternative Title (1)

dotancohen (1015143) | about three weeks ago | (#47791547)

And the state of the hardware. Some unknown number of systems on the real curiosity are degraded to the point of malfunctioning; And they have little to no way of exactly measuring what and where.

Opportunity. Curiosity is on the other side of Mars, nuturing holes in its wheels and looking for cats to kill.

Alternative Title (0)

Anonymous Coward | about three weeks ago | (#47791377)

Right, cause trying to extend the life of a 2.5 billion dollar device which was intended to last ~92 days and has instead lasted 4,072 days so far would be considered a total failure it that attempt failed and bricked it. We should just let it continue to crash.

Is it running Windows? (2)

mark_reh (2015546) | about three weeks ago | (#47791079)

Is it?

Re:Is it running Windows? (4, Informative)

Psychotria (953670) | about three weeks ago | (#47791119)

You're probably joking, but the OS is VxWorks.

MRAM now or some other tech (0)

Anonymous Coward | about three weeks ago | (#47791213)

What non-volatile memory would you use now

Why is it not trivial? (1)

nurb432 (527695) | about three weeks ago | (#47791233)

Why didn't they plan ahead for this sort of operation in the beginning, making it painless and 'reliable' ( as possible ).

Re:Why is it not trivial? (1)

beelsebob (529313) | about three weeks ago | (#47791281)

Who says they didn't?

Re:Why is it not trivial? (0)

Anonymous Coward | about three weeks ago | (#47791321)

wtf? Obviously, they did plan ahead, which is why they are able to reflash the chip. But if you mean plan ahead by running patrol reads or scrubbing, I imagine they didn't waste time and resources in much the same way as you dont to an extensive memory diagnostic test before you open an email. What kind of handwaving armchair wannabe are you?

Re:Why is it not trivial? (1)

nurb432 (527695) | about three weeks ago | (#47791359)

What kind of handwaving armchair wannabe are you?

One that plans ahead well enough that this would not considered 'news'. Instead it would be just SoP.

Re:Why is it not trivial? (2)

SeaFox (739806) | about three weeks ago | (#47791329)

Why didn't they plan ahead for this sort of operation in the beginning, making it painless and 'reliable' ( as possible ).

That's a joke, right? We are talking about one of the two rovers [xkcd.com] that was sent to Mars on a mission planned to only last 90 days. They didn't see "flash memory wearing out from use" as a contingency they needed to plan for.

Re:Why is it not trivial? (0)

Nimey (114278) | about three weeks ago | (#47791905)

You're a poster child for Dunning-Kruger [wikipedia.org] : some random on the Internet who thinks he's smarter than the folks who designed a Mars rover that lasted over 10 years past its 90-day expected life.

Re:Why is it not trivial? (0)

nurb432 (527695) | about two weeks ago | (#47792037)

Who said i *think* that? I am smarter, which is an actual fact. ( tho to you, not knowing who i really am, I could appear to be a random person so i will give you that )

Re:Why is it not trivial? (0)

Anonymous Coward | about two weeks ago | (#47792187)

You are a tool. It's a "fact" that you are smarter? Prove it, asshole.

Re:Why is it not trivial? (1)

nurb432 (527695) | about two weeks ago | (#47792323)

Don't need to prove anything to a potty mouthed coward.

Re:Why is it not trivial? (1)

Nimey (114278) | about two weeks ago | (#47792203)

Put up or shut up: who are you, really?

Re:Why is it not trivial? (0)

nurb432 (527695) | about two weeks ago | (#47792467)

Ever hear of VX gas?

Re:Why is it not trivial? (1)

Nimey (114278) | about two weeks ago | (#47792473)

If you're going to troll and be full of shit, save us both time and say so up front.

Re:Why is it not trivial? (0)

nurb432 (527695) | about two weeks ago | (#47792501)

It was just a question. It had nothing to do with who I am. Think of it as a quiz to see if you deserve to know who i am.

However, you failed question #1 miserably, by not answering a simple yes/no question, and instead being a smart-ass. Thus not deserving.

Re:Why is it not trivial? (1)

Nimey (114278) | about two weeks ago | (#47792503)

Boring troll is boring. Put your back into it, boy.

Re:Why is it not trivial? (0)

nurb432 (527695) | about two weeks ago | (#47792561)

See, the problem is i wasn't doing that. You simply failed to impress me enough to deserve the truth. I rarely give anyone that chance, so you should feel special. But its nice to know you performed as expected.

Re:Why is it not trivial? (1)

Nimey (114278) | about two weeks ago | (#47792607)

I don't believe a word of it.

Re:Why is it not trivial? (1)

Nimey (114278) | about two weeks ago | (#47792491)

Further, if this is you:
http://www.fiero.nl/cgi-bin/fi... [fiero.nl]

You're conclusively an idiot. Only an idiot believes in homeopathy.

Re:Why is it not trivial? (1)

nurb432 (527695) | about two weeks ago | (#47792521)

Sorry, not the same person. No "nickname" is overly unique in the online world these days. Its not 1980 anymore.

But i dont want to blow my karma.

Re:Why is it not trivial? (1)

Nimey (114278) | about two weeks ago | (#47792549)

Yeah, bullshit. Your nickname has enough entropy that it's exceedingly unlikely this is not you.

Re:Why is it not trivial? (1)

nurb432 (527695) | about two weeks ago | (#47792601)

Nah, its not. But believe what you wish, it is a free country. ( assuming a US citizen here )

Re:Why is it not trivial? (1)

Nimey (114278) | about two weeks ago | (#47792633)

You really need to level-up your trolling. This is 101-level shit, son.

Re:Why is it not trivial? (1)

nurb432 (527695) | about two weeks ago | (#47792689)

You are more than welcome to get a court order and demand IP addresses, then compare them. I'm sure both places log IP+posts.

Re:Why is it not trivial? (1)

Nimey (114278) | about two weeks ago | (#47792701)

*snore*

Re:Why is it not trivial? (0)

nurb432 (527695) | about two weeks ago | (#47792721)

Your choice. I offered a valid solution.

Format (0)

Anonymous Coward | about three weeks ago | (#47791269)

Just format, not reformat. /troll

Assumptions (1)

DaMattster (977781) | about three weeks ago | (#47791283)

I believe NASA is operating under the assumption that the rover's on board flash memory is still serviceable. 10 years ago flash memory was still in its relative infancy. A reformat and reload risks bricking the rover completely.

Re:Assumptions (2)

beelsebob (529313) | about three weeks ago | (#47791301)

I believe you're assuming that the flash used on a rover that went to mars, and encounters all kinds of crazy radiation, is in some way similar to the crappy OCZ thing you stuck in your PC 10 years ago.

Re:Assumptions (1)

ssufficool (1836898) | about three weeks ago | (#47791617)

And that is why RAID 0 wear leveling is useful in this case.

Re:Assumptions (0)

Nimey (114278) | about three weeks ago | (#47791897)

You're a poster child for Dunning-Kruger [wikipedia.org] : some random on the Internet who thinks he's smarter than the folks who designed a Mars rover that lasted over 10 years past its 90-day expected life.

Failing flash cells? (1)

Twinbee (767046) | about three weeks ago | (#47791533)

I didn't realize they used OCZ for the storage tech. ;)

Re:Failing flash cells? (1)

Anonymous Coward | about three weeks ago | (#47791667)

It was designed to last 3 months and failed after 10 years.
If OCZ was involved, it'd be the other way around. ;)

I"d hate to be the guy (1)

TigerPlish (174064) | about three weeks ago | (#47791689)

I'd hate to be the guy a) pitching this operation at the change control meeting, and b) the guy signing off on this change.

Re:I"d hate to be the guy (0)

Anonymous Coward | about three weeks ago | (#47791939)

Anymoron can use a computer, if you need things like
Control and change, like Hope and change, put an Oxymoron in charge.

I told them (0)

Anonymous Coward | about three weeks ago | (#47792035)

I told them to use TRIM, but noooo!

Rebooting? (1)

david999 (941503) | about two weeks ago | (#47792133)

If it is rebooting all the time may I suggest do not use Windows as the OS : )

It worked on Spirit (4, Interesting)

lemur3 (997863) | about two weeks ago | (#47792279)

they had to do this type of thing on spirit shortly after it arrived on mars..

read more here: http://trs-new.jpl.nasa.gov/ds... [nasa.gov]

or the PDF linked therin here http://trs-new.jpl.nasa.gov/ds... [nasa.gov]

its got all sorts of awesome details.

We commanded a shutdown, which terminated the
current communication window, and the loss of signal occurred at the predicted time. Fifty minutes later, we commanded a beep at 7.8125 bps to alert us if the shutdown command did not work, and much to our disappointment, the beep was received!

really a fun read. ..im guessing theyll be doing a lot of similar stuff

Launch 2 rovers (0)

Anonymous Coward | about two weeks ago | (#47792289)

What would be the marginal cost of replicating the rover and launching a second rover at the same time? They could do twice as many experiments and explore two different areas.

Protip (0)

Anonymous Coward | about two weeks ago | (#47792335)

Reformatting your flash will not solve the problem of cell wearout.

What idiots used flash on a Mars mission anyway? We're talking about a multi-million dollar rover with a pretty much "sky's the limit" budget... and they use flash.

How hard can it be (-1)

Anonymous Coward | about two weeks ago | (#47792457)

People at NASA, how dumb can you be.
Your rover a million miles from me.
When it starts to crash.
And rebooting from flash.
Just tell it to FORMAT C:

Lucky for us not unionized work (0)

Anonymous Coward | about two weeks ago | (#47792499)

Yeah Yeah I'll go and fix that!

But I am claiming 53 cents per kilometers as per stipulated in my collective agreement.

I am also taking food and other expenses too.

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