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Copying 10,000 files? Any chance of losing some of them?
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I won't say it's impossible that a file or two won't get corrupted, but I have confidence that nearly (99%) every file would get backed up with no problems. If anything move the files in batches (i.e. 2,000 at a time).
99% is a _horribly_ low success rate for something as important as file copying.
Fortunately, GimmeSlack12, the success rate is much higher. Rest at ease: if you attempt to copy files using Finder, and Finder does not report any failure messages, it means that none of your files were overlooked. You can feel secure in the knowledge that your files were safely copied without looking through them all.
Edit: If you want, you could Get Info on each folder and check that they are the same size by way of confirmation. But don't worry, they will be.
I should say that, though the copy operation is not a significant point of failure, physical disks are a significant point of failure, so watch out for old / crappy harddrives. The safest place is actually optical media like a DVD.
Fortunately, GimmeSlack12, the success rate is much higher. Rest at ease: if you attempt to copy files using Finder, and Finder does not report any failure messages, it means that none of your files were overlooked. You can feel secure in the knowledge that your files were safely copied without looking through them all.
Edit: If you want, you could Get Info on each folder and check that they are the same size by way of confirmation. But don't worry, they will be.
I should say that, though the copy operation is not a significant point of failure, physical disks are a significant point of failure, so watch out for old / crappy harddrives. The safest place is actually optical media like a DVD.
You know the forums are just impossible to anticipate. If I say 100% Go For it No Problem! I'd get crap from someone saying this or that could go wrong and that I'm full of it.
Yet when I'm realistic about a 99% success rate I get "horribly low success rate". Jeez, I guess 99.9999999%. Happy? Talk about splitting hairs.
Yet when I'm realistic about a 99% success rate I get "horribly low success rate". Jeez, I guess 99.9999999%. Happy? Talk about splitting hairs.
99% and 99.9999999% are extremely different numbers.
If there were only a 99% success rate, a 10,000 file copy missed 100 files! Can you imagine? No installation would ever be successful!
If there were only a 99% success rate, a 10,000 file copy missed 100 files! Can you imagine? No installation would ever be successful!
But we aren't talking about the installation of anything. So your post is irrelevant.
(See what I did there?)
As a rule for "good enough": The copy can go wrong for reasons that have nothing to do with the OS. Like a meteorite coming down through the roof and destroying your Mac. So what is your expectancy of success if you take that into account?
Just checked: Hard drives have an MTBF (mean time between failures) of about 500,000 hours. If you copy 10,000 files in one minute, chances that your hard drive fails fatally during the copy is one in 30 million. Probability of success is therefore at most 99.999997 percent.
Swarm of bees is actually what I had factored in.
EDIT: I like the way you think Gnasher.
files are copied in an installation... for all we know he could have been talking about an installation that involved copying 10,000 files. A 99% success rate in copying files is really, really low. But, its not 100%. But of those times that it fails, it will probably tell you something f'ed up, (or you will see the meteorite crater where your computer used to be, as mentioned above) better improving your odds for a successful transfer by allowing you to do it again.
Bottom line: you're fine unless it tells you there was a problem.
Pretty sure he wasn't talking about an installation. But that wasn't really my point anyway for that post, I was just splitting some more hairs
Semantics on percentile chances aside, if the original poster is just talking about copying files to another drive, then the chances of problems are functionally nil past what you usually have when working on a computer (lighting strike, massive spontaneous hardware failure, etc); it just doesn't happen. I routinely move hundreds of thousands of files around between drives (both locally and over a network) for institutional server backups without any issue.
If something DID go wrong, the OS should tell you, though the issue is always some sort of permission issue, not hardware problems. To be extra paranoid, any number of backup or synchronization programs will double-check the files after copy to make sure there were no problems; I use Sync personally (also because it can be set to only copy changed files, which with a volume containing 200,000 files is nice).
If we're talking about optical disc, the answer is "if there's an error burning the disc, the Finder or Disk Utility will tell you when it verifies it". The verification process reads back the entire burned disc and compares it to the original files to make sure there aren't any problems.
Optical discs can, of course, go bad later, either due to scratching or (if you wait long enough) media degradation due to sunlight, manufacturing error, whatever, but that is unavoidable with any media format (eventually SOMETHING is going to go bad--even paper rots). Generally if you have a good burn, and decent media, and you store it carefully, it'll be good for quite some time.
When I'm being extra-paranoid, I burn the same archival copy onto two different brands of media, and every once in a while (maybe annually) check an individual disc from each of the spindles I bought, figuring that if one goes, they're probably all going, so I'll notice it, and that two brands from two different spindles aren't likely to both spontaneously "rot" at the same time.
If something DID go wrong, the OS should tell you, though the issue is always some sort of permission issue, not hardware problems. To be extra paranoid, any number of backup or synchronization programs will double-check the files after copy to make sure there were no problems; I use Sync personally (also because it can be set to only copy changed files, which with a volume containing 200,000 files is nice).
If we're talking about optical disc, the answer is "if there's an error burning the disc, the Finder or Disk Utility will tell you when it verifies it". The verification process reads back the entire burned disc and compares it to the original files to make sure there aren't any problems.
Optical discs can, of course, go bad later, either due to scratching or (if you wait long enough) media degradation due to sunlight, manufacturing error, whatever, but that is unavoidable with any media format (eventually SOMETHING is going to go bad--even paper rots). Generally if you have a good burn, and decent media, and you store it carefully, it'll be good for quite some time.
When I'm being extra-paranoid, I burn the same archival copy onto two different brands of media, and every once in a while (maybe annually) check an individual disc from each of the spindles I bought, figuring that if one goes, they're probably all going, so I'll notice it, and that two brands from two different spindles aren't likely to both spontaneously "rot" at the same time.