Einstein on SSD's

In my opinion there are major problems that arise.
First the SSD got 80GB (74GB real useable) but after the installation of the OS and some programs there are only 30 GB left. So 11 years become more like 4 years.

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Not true. The controllers are smarter than you give them credit for. They implement wear leveling which occasionally moves static data around so that all of the flash is written at about the same time. On an SSD the write amplification (difference between how much you write and how much it writes) is only a few percent. A large part of how they do this is the use of scratch space. The drive might look full to your OS but it still has some spare space, typically 7% on consumer models so even when the drive is full and you make a small write it's only writing 4k of data somewhere, not erasing and rewriting 512k.

Second thing: What truly kills a SSD are the random writes. I think for the 80GB models that is 3.5TB. If you use a tool to benchmark the random writes, you can kill the SSD in under a day (because the random writes are so high 50MB/s).

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Again not true. Your random writes will be spread out over the entire drive. The fastest way to kill it would be with sequential writes at ~75MB/sec for an intel drive (~175MB/sec for an indilinx barefoot based drive). For the intel drive that's 6.4PB of writes/day or 81 complete writes to the drive. This would require ~4 months to hit the 10k writes the drive is rated for. People have done these sort of exercises, and at the 10k point the drives lost about 10% of their rated capacity.

So after scaring everybody: The SSD needs unused space to compensate the broken blocks. It doesn´t use the free space in a partition but the space, which is unpartitioned. So to enhance your drives lifespan, you have to fully erease your SSD and instead of building a 74 GB partition you create a 65GB partition. So the spare space is doubled and so the lifespan (for typical usage). If you know, that you don´t need the full space on the drive and don´t partition the full disk. (This adds to the costs of a SSD). There've been people who've done this, and at the 10k writes point the drives were still at ~90% of capacity because they removed the chunks of the flash chips that were dieing fastest from service before any data was lost. Unfortunately I haven't seen any tests that continued the run for some more months to see how quickly the remainder of the flash died. I'm curious about this, but not curious enough to destroy a $100+ device to find out.

That sort of activity is massively outside the bounds of normal consumer computer use. Unless you spend your time compiling very large software programs over and over (while forcing new writes of all the intermediate files each time) or doing video editing with huge numbers of saves, you'll only do a few to a few dozen GB/day of writes; at which point the flash chips will die of old age in a decadish, long before you reach their write lifetime (my post above contained a math error, under the circumstances described the drive would need 109 years, not 10.9 to reach the write limit).

The only real world situation where you would have anything approaching the theoretical maximum write rate of an SSD would on some types of servers. To protect against that they use flash chips that only have 50% of the capacity of what's used in consumer models but which good for 100k writes, which is sufficient to give the SSDs a longer useful lifetime than the servers they're installed in.

The only sort of flash you might be able to kill in a few days would be a memory card or a USB stick, because they use the cheapest, crappiest flash available, and their bottom spec controllers are less capable of minimizing the write amplification penalty.

The rest of your advise about how to paritition the SSD is nonsense because you'd have to be writing hundreds of gigabytes/day to write the chips to death before they died of old age.