by Tdarcos » Sun Oct 30, 2011 12:47 pm
Flack wrote:I don't trust DVD-R or CD-R media for backups.
Oh please, don't bullshit me. The minimum expected retention time for CDs was ten years when they came out, and now averages about 100 years if I remember.
They're simply too unreliable for long term storage.
"Don't piss down my back and tell me it's raining." - Captain Fletcher,
The Outlaw Josie Wales
Removable magnetic media has a substantially lower reliability level than optical media. Here's a table I found
http://www.dpconline.org/advice/preserv ... mats/media comparing media lifetime figures, at room temperature, D3 magnetic tape - most certainly made to much higher standards than floppy disc - has about 3 years lifespan, CD and DVD have 10 years. At archival conditions, 20% relative humidity at 10 degrees celsius (50 F), tape is good for about 50 years, disc about 75 years. So I was wrong about 100 years but it's still at least 50% more.
Commercial installations depend on tape backup for "bet the company" data, that if backups fail, so does the company, so they must be significantly reliable enough for critical use. But their reliability is at best 1/2 that of optical media. Mag tape cartridge for backup has three advantages: reduced labor costs because you can automate backups without someone having to be there, and the equipment for automated tape backup is about 1/5 of automated disc backup. You can set up an autoloader for tape for a couple grand vs. about 10 grand for a programmable DVD autoloader. The third advantage is that tape cartridges can do about 60 GB each vs. 4 GB for DVD. (I've not seen Blu-Ray available in standalone automated duplicators yet, or the numbers would change even further). So with very large databases, in the dozens of gigabytes it means less likelihood of files having to be broken across media. Although with tapes costing about $12 each they had better have much higher capacities over DVD or Blu.
No, all I trust now are floppy disks -- 5.25, preferred.
Oh really? Soft magnetic floppies, the worst possible storage medium in terms of ease of damage and destruction. If you're going to bullshit me at least try to think up less ridiculous and obvious lies. At least if you had said 3 1/2 disks, which hold more and are more resistant to damage, that might have had slightly more credibility.
The worst-made flash media today such as jump drives are far more reliable than the best made floppy disc, which are basically obsolete technology. You should have said you only trust Smartmedia for removable storage, because it uses much less dense data packing than today's SD or flash. Again, then, the argument would have at least had a slight ring of credibility. The maximum size of a smartmedia chip, a little bit bigger than twice a full-size SD card, is about 128 meg vs. as much as 32 or possibly 64 gb for SD/flash.
My current MP3 collection takes up approximately 600GB of space, or (roughly) 600,000 megabytes. A 5.25" floppy disk, assuming DS/HD, stores (after formatting) roughly 1.2 megabytes -- meaning, I'll need approximately half a million floppy disks to make one backup -- or, a million for two full backups, if you are to keep one copy offsite.
And your average MP3 would have to be split across 4 disks. (MP3s are already essentially compressed so compressing them won't gain much.) So with the average MP3 being about 4 meg or so, what you are saying is your music collection consists of about 120,000 MP3s?
I did just add a couple of large bookshelves down in the tornado shelter that are big enough to store my share of the the diskettes. Do you have room to hold this amount of media at your place?
Let's see. A 5 1/2" disk probably requires about 1 foot of space per 100 disks, if I remember from the days I had trays and trays of them, probably 20 years ago. So, given that this would require 50,000 linear feet of shelf space, and you could fit them into a 6" shelf space, you'd need a 12 shelf bookshelf - each shelf 6" high, going up about 6 1/2 feet (using not very thick plywood), so 50,000 feet divided by 12 is 4167 feet, so basically you'd need a shelter having 3/4 of a mile of shelf space 6 1/2' high. That, at a minimum, is a room about 300 feet long and 20 feet wide, presuming you use space compression where the shelves are movable so that you don't have a corridor between shelves when it's not being used. (Doctors and veterinarians offices have these, they'll have three or four shelf units with only one opening between them since you don't need to waste space because not every shelf needs to be simultaneously accessible.)
If your collection was actually that large to have listened to all of it would mean you'd have to listen to a different song every 4 minutes without sleeping for a year and a half. Call it 5 years if you did it for 8 hours a day. Presuming you were listening to 25 new, different songs a day - possible for a person who works and commutes 10 hours a day and has to sleep at least 6-8 hours - that would only take you 15 years.
Exactly how did you get the time to rip tracks from anywhere upwards of 12,000 compact discs or at least 60,000 phonorecords?
What did you do, trade collections with other people?
If your collection was that large then I presume you'd just have it on two separate terabyte or larger hard drives, either in separate machines or one being an external. A 1 TB drive sells for about $60, a 2 TB about $90.
But if you seriously do have 120,000 MP3s then let me know, it might actually be worth it. Basically for large-scale storage, DVD and Blu-Ray are about equivalent to hard drives, at about 6c per gigabyte, a terabyte drive (1000 billion) at around $60 is equivalent to DVD at 24c/4 GB or BRD at $1 for 25gb.
[quote="Flack"]I don't trust DVD-R or CD-R media for backups.[/quote]
Oh please, don't bullshit me. The minimum expected retention time for CDs was ten years when they came out, and now averages about 100 years if I remember.
[quote]They're simply too unreliable for long term storage.[/quote]
"Don't piss down my back and tell me it's raining." - Captain Fletcher, [i]The Outlaw Josie Wales[/i]
Removable magnetic media has a substantially lower reliability level than optical media. Here's a table I found http://www.dpconline.org/advice/preservationhandbook/media-and-formats/media comparing media lifetime figures, at room temperature, D3 magnetic tape - most certainly made to much higher standards than floppy disc - has about 3 years lifespan, CD and DVD have 10 years. At archival conditions, 20% relative humidity at 10 degrees celsius (50 F), tape is good for about 50 years, disc about 75 years. So I was wrong about 100 years but it's still at least 50% more.
Commercial installations depend on tape backup for "bet the company" data, that if backups fail, so does the company, so they must be significantly reliable enough for critical use. But their reliability is at best 1/2 that of optical media. Mag tape cartridge for backup has three advantages: reduced labor costs because you can automate backups without someone having to be there, and the equipment for automated tape backup is about 1/5 of automated disc backup. You can set up an autoloader for tape for a couple grand vs. about 10 grand for a programmable DVD autoloader. The third advantage is that tape cartridges can do about 60 GB each vs. 4 GB for DVD. (I've not seen Blu-Ray available in standalone automated duplicators yet, or the numbers would change even further). So with very large databases, in the dozens of gigabytes it means less likelihood of files having to be broken across media. Although with tapes costing about $12 each they had better have much higher capacities over DVD or Blu.
[quote]No, all I trust now are floppy disks -- 5.25, preferred.[/quote] Oh really? Soft magnetic floppies, the worst possible storage medium in terms of ease of damage and destruction. If you're going to bullshit me at least try to think up less ridiculous and obvious lies. At least if you had said 3 1/2 disks, which hold more and are more resistant to damage, that might have had slightly more credibility.
The worst-made flash media today such as jump drives are far more reliable than the best made floppy disc, which are basically obsolete technology. You should have said you only trust Smartmedia for removable storage, because it uses much less dense data packing than today's SD or flash. Again, then, the argument would have at least had a slight ring of credibility. The maximum size of a smartmedia chip, a little bit bigger than twice a full-size SD card, is about 128 meg vs. as much as 32 or possibly 64 gb for SD/flash.
[quote]My current MP3 collection takes up approximately 600GB of space, or (roughly) 600,000 megabytes. A 5.25" floppy disk, assuming DS/HD, stores (after formatting) roughly 1.2 megabytes -- meaning, I'll need approximately half a million floppy disks to make one backup -- or, a million for two full backups, if you are to keep one copy offsite.[/quote]
And your average MP3 would have to be split across 4 disks. (MP3s are already essentially compressed so compressing them won't gain much.) So with the average MP3 being about 4 meg or so, what you are saying is your music collection consists of about 120,000 MP3s?
[quote]I did just add a couple of large bookshelves down in the tornado shelter that are big enough to store my share of the the diskettes. Do you have room to hold this amount of media at your place?[/quote]
Let's see. A 5 1/2" disk probably requires about 1 foot of space per 100 disks, if I remember from the days I had trays and trays of them, probably 20 years ago. So, given that this would require 50,000 linear feet of shelf space, and you could fit them into a 6" shelf space, you'd need a 12 shelf bookshelf - each shelf 6" high, going up about 6 1/2 feet (using not very thick plywood), so 50,000 feet divided by 12 is 4167 feet, so basically you'd need a shelter having 3/4 of a mile of shelf space 6 1/2' high. That, at a minimum, is a room about 300 feet long and 20 feet wide, presuming you use space compression where the shelves are movable so that you don't have a corridor between shelves when it's not being used. (Doctors and veterinarians offices have these, they'll have three or four shelf units with only one opening between them since you don't need to waste space because not every shelf needs to be simultaneously accessible.)
If your collection was actually that large to have listened to all of it would mean you'd have to listen to a different song every 4 minutes without sleeping for a year and a half. Call it 5 years if you did it for 8 hours a day. Presuming you were listening to 25 new, different songs a day - possible for a person who works and commutes 10 hours a day and has to sleep at least 6-8 hours - that would only take you 15 years.
Exactly how did you get the time to rip tracks from anywhere upwards of 12,000 compact discs or at least 60,000 phonorecords?
What did you do, trade collections with other people?
If your collection was that large then I presume you'd just have it on two separate terabyte or larger hard drives, either in separate machines or one being an external. A 1 TB drive sells for about $60, a 2 TB about $90.
But if you seriously do have 120,000 MP3s then let me know, it might actually be worth it. Basically for large-scale storage, DVD and Blu-Ray are about equivalent to hard drives, at about 6c per gigabyte, a terabyte drive (1000 billion) at around $60 is equivalent to DVD at 24c/4 GB or BRD at $1 for 25gb.