4 ms·

My point is, they have been affected. I think most people have seen bitflips. >2009 Google's paper "DRAM Errors in the Wild: A Large-Scale Field Study" says th

My point is, they have been affected. I think most people have seen bitflips. >2009 Google's paper "DRAM Errors in the Wild: A Large-Scale Field Study" says that there can be up to 25000-75000 one-bit FIT per Mbit (failures in time per billion hours), which is equal to 1 - 5 bit errors per hour for 8GB of RAM after my calculations. Paper says the same: "mean correctable error rates of 2000–6000 per GB per year". https://stackoverflow.com/questions/2580933/cosmic-rays-what-is-the-probability-they-will-affect-a-program https://stackoverflow.com/questions/2580933/cosmic-rays-what... I believe bitflips are far more common than people realize. I see weird shit all the time from my users that is only explainable due to bizarre software bugs or bitflips.

buran77 6y ago
But behringer, regular users don't see bitflips, they see "a random error", a random reboot, a random green pixel in a photo. That's if they even consciously observed anything at all. You yourself said those could have a dozen other root causes. I for one have not actually observed a bitflip (so something that I can actually consciously detect as an issue) in a decade. No unexpected reboots, no unexpected file corruption, etc., nothing that made me say "weird, must be some memory corruption". Don't get me wrong, I'm all for ECC memory, I practically showed the value of ECC after intentionally running the same multi-day Matlab job several times on a non-ECC machine with different results just to prove this very point. But you use your deeper knowledge to assume what someone with shallow knowledge and interest wants or needs, and that will almost always be off mark. Your car does not have a roll cage. Normal computers do not have ECC memory.
- projct 6y ago
  "Your car does not have a roll cage" No but the crash structures are one of the areas where we are absolutely trying to recreate the effect of a rollcage without the weight. The weight putting constraints on fuel efficiency is the big issue there. For ECC, there's no reason to really expect that adding ECC to everything would really make things too expensive or slow long term. For a long time the reason why desktops did not have ECC was pretty much because intel wanted people who really need ECC to buy Xeons.
  - buran77 6y ago
    > No but the crash structures are one of the areas where we are absolutely trying to recreate the effect of a rollcage without the weight Exactly like how we try to recreate the effect of ECC hardware but without its "weight" (cost, complexity). For a problem that's not nearly as visible or life and death. > too expensive or slow long term Not "too" expensive long term still means more expensive especially short term, like when the person buys it. For an issue no average consumer is actually frustrated about. Why are we still debating why those consumers don't care about ECC? How is it different from hot swappable RAM for the average Joe? They'll upgrade or expand their RAM more often than they'll get frustrated about the effect of bitflips. So why not have hot swappable memory? Because as much as I'd love hot swappable anything, regular consumers neither care about it nor want to pay for it.
Dylan16807 6y ago
Bit flips are reasonably common, but mean is of very little use when one stick can throw no errors and another stick can throw thousands. A more useful quote is "About a third of machines and over 8% of DIMMs in our fleet saw at least one correctable error per year."

buran77 6y ago

But behringer, regular users don't see bitflips, they see "a random error", a random reboot, a random green pixel in a photo. That's if they even consciously observed anything at all. You yourself said those could have a dozen other root causes. I for one have not actually observed a bitflip (so something that I can actually consciously detect as an issue) in a decade. No unexpected reboots, no unexpected file corruption, etc., nothing that made me say "weird, must be some memory corruption". Don't get me wrong, I'm all for ECC memory, I practically showed the value of ECC after intentionally running the same multi-day Matlab job several times on a non-ECC machine with different results just to prove this very point. But you use your deeper knowledge to assume what someone with shallow knowledge and interest wants or needs, and that will almost always be off mark. Your car does not have a roll cage. Normal computers do not have ECC memory.

projct 6y ago
"Your car does not have a roll cage" No but the crash structures are one of the areas where we are absolutely trying to recreate the effect of a rollcage without the weight. The weight putting constraints on fuel efficiency is the big issue there. For ECC, there's no reason to really expect that adding ECC to everything would really make things too expensive or slow long term. For a long time the reason why desktops did not have ECC was pretty much because intel wanted people who really need ECC to buy Xeons.
- buran77 6y ago
  > No but the crash structures are one of the areas where we are absolutely trying to recreate the effect of a rollcage without the weight Exactly like how we try to recreate the effect of ECC hardware but without its "weight" (cost, complexity). For a problem that's not nearly as visible or life and death. > too expensive or slow long term Not "too" expensive long term still means more expensive especially short term, like when the person buys it. For an issue no average consumer is actually frustrated about. Why are we still debating why those consumers don't care about ECC? How is it different from hot swappable RAM for the average Joe? They'll upgrade or expand their RAM more often than they'll get frustrated about the effect of bitflips. So why not have hot swappable memory? Because as much as I'd love hot swappable anything, regular consumers neither care about it nor want to pay for it.

Dylan16807 6y ago

Bit flips are reasonably common, but mean is of very little use when one stick can throw no errors and another stick can throw thousands. A more useful quote is "About a third of machines and over 8% of DIMMs in our fleet saw at least one correctable error per year."