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I think ECC is inevitable. With 128GB DIMMs being produced now and NV-DIMMs (DDR4 flash-on-dimm) just around the corner, some kind of hardware error detection i
by melted 11y ago
I think ECC is inevitable. With 128GB DIMMs being produced now and NV-DIMMs (DDR4 flash-on-dimm) just around the corner, some kind of hardware error detection is necessary.
This is similar to high capacity spinning drives. With smaller ones you could just go with RAID5 and not worry about anything, but when drives are 3-4TB and up, you have to use RAID6, because the spec error rate becomes too high to rely on a single parity drive.
Here, too, when you machine has 1-2TB of hybrid RAM/NVM you HAVE TO have some way to detect failures, even if it's not particularly good. Performance characteristics of RAM preclude the more robust algorithms such as wide (32bit) CRC from being used (narrower CRC could still be doable in hardware, though), but parity is a complete no brainer as the first step.
- snaky 11y agoRAID 6 is not an option with drives big enough because of rebuild time. https://storagemojo.com/2010/02/27/does-raid-6-stops-working-in-2019/ https://storagemojo.com/2010/02/27/does-raid-6-stops-working...
- melted 11y agoRebuild time is a problem, I agree. But not as huge of a problem as outright data loss.
- snaky 11y agoRAID is not the solution for data loss problem, never was, never will. There is backup for that.
- melted 11y agoBackup is never current, and it takes time to restore. RAID has its place. So much so, in fact, that there are now erasure-coded distributed filesystems at Google and elsewhere, reliably storing exabytes of data on super shitty disks.
- mrb 11y agoNitpick: neither RAID 6, nor RAID 5 are an option. Leventhal's point is that triple-parity (eg. ZFS raidz3) becomes necessary.
- snaky 11y agoI think the main point is that there is no "RAID is the solution for all our problems" anymore.
- codinghorror 11y agoThere were rumblings from a fruit related technology company that ECC may in fact be required in future memory hardware because the risk of error becomes too high without it. This makes total sense to me, I am frankly surprised that ECC is still considered a weird premium upsell considered worthy only for servers and server farms. Shouldn't every computer be reliable?
- melted 11y agoIt's a "premium upsell" for the same reason why we still have 1366x768 screens on laptops: PC manufacturers don't give a shit and they'd rather save $1 per unit. As to Apple, I'm not sure why they don't support ECC in anything other than MacPro. IMO they should.