I just concluded a decade long experiment.
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I just concluded a decade long experiment. I had a USB flash drive in a jar buried in my back yard since 2015. I dug it up, plugged it in and it suffered no data loss after 11 years idle underground.
It's a usless experiment but everyone needs hobbies.
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I just concluded a decade long experiment. I had a USB flash drive in a jar buried in my back yard since 2015. I dug it up, plugged it in and it suffered no data loss after 11 years idle underground.
It's a usless experiment but everyone needs hobbies.
@Aaron_DeVries
While doing environmental testing on a helicopter payload, I learned that NVMe drives (and perhaps all SSDs) can write data at high ambient temperatures >40 C, but the data is less permanent than if you write data at normal ambient temperatures.
So on hot days we had to hurry and copy our 4TB drives after the flight because the data had a half-life of a dozen hours or so.That phenomenon is already documented, but I don't think it's widely known.
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@Aaron_DeVries
While doing environmental testing on a helicopter payload, I learned that NVMe drives (and perhaps all SSDs) can write data at high ambient temperatures >40 C, but the data is less permanent than if you write data at normal ambient temperatures.
So on hot days we had to hurry and copy our 4TB drives after the flight because the data had a half-life of a dozen hours or so.That phenomenon is already documented, but I don't think it's widely known.
@swope That's actually fascinating, I wonder why that is.
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@swope That's actually fascinating, I wonder why that is.
@Aaron_DeVries
I would also like to know. -
@Aaron_DeVries
While doing environmental testing on a helicopter payload, I learned that NVMe drives (and perhaps all SSDs) can write data at high ambient temperatures >40 C, but the data is less permanent than if you write data at normal ambient temperatures.
So on hot days we had to hurry and copy our 4TB drives after the flight because the data had a half-life of a dozen hours or so.That phenomenon is already documented, but I don't think it's widely known.
So, I guess we should store our testaments on an SSD while it is in liquid nitrogen
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So, I guess we should store our testaments on an SSD while it is in liquid nitrogen
@sudo200
Lol. Ymmv -
@Aaron_DeVries
While doing environmental testing on a helicopter payload, I learned that NVMe drives (and perhaps all SSDs) can write data at high ambient temperatures >40 C, but the data is less permanent than if you write data at normal ambient temperatures.
So on hot days we had to hurry and copy our 4TB drives after the flight because the data had a half-life of a dozen hours or so.That phenomenon is already documented, but I don't think it's widely known.
@swope @Aaron_DeVries I once saw a datasheet for an Intel SSD, which basically said it likes being run hot and stored cold, and that combination gave the longest data retention lifetime. Hot/hot, not so much.
If I remember correctly, that's because higher temperatures make it easier for electrons to escape from the floating gates. Which is bad for data retention, but as long as the drive is powered on the firmware can handle that by re-writing the data occasionally. But it also means deliberate erasures are easier and cause less physical damage, so the SSD degrades slower if it's run hot. And after enough use, that matters more than the effect of temperature on the durability of any individual write.
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@swope @Aaron_DeVries I once saw a datasheet for an Intel SSD, which basically said it likes being run hot and stored cold, and that combination gave the longest data retention lifetime. Hot/hot, not so much.
If I remember correctly, that's because higher temperatures make it easier for electrons to escape from the floating gates. Which is bad for data retention, but as long as the drive is powered on the firmware can handle that by re-writing the data occasionally. But it also means deliberate erasures are easier and cause less physical damage, so the SSD degrades slower if it's run hot. And after enough use, that matters more than the effect of temperature on the durability of any individual write.
This is interesting.
Sadly, we didn't get the internal NVMe temperatures during our environmental testing.
I think the drives' spec said 35°C ambient for the max operating temperature, and we would typically see 45°C internal from `nvme smart-log /dev/nvme0` (I might not be remembering the command correctly).
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This is interesting.
Sadly, we didn't get the internal NVMe temperatures during our environmental testing.
I think the drives' spec said 35°C ambient for the max operating temperature, and we would typically see 45°C internal from `nvme smart-log /dev/nvme0` (I might not be remembering the command correctly).
I kinda supposed that there was an ideal temperature for writing that the drives try to maintain, but when ambient is too high they can't. Then what gets written is on the edge of being readable, and normal temperature storage losses degrade that in a few hours.
Lots of hand waving on my part. We just made a procedure and carried on. But it would be pretty insidious to look at your data right after recording and it looks good, but it's gone the next week.
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