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Should I buy ECC memory? (2015)

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201–210 of 237 posts

Re: Should I buy ECC memory? (2015)

#201
post #199
post #197

Earlier quoted context omitted.

Huh? If you're going to swap a faulty hard drive you want to power off anyway.

I hotswap drives all the time, it's not a problem and makes a harddrive swap a 30 second task instead of a 10 minute task and doesn't incur downtime either.

Most consumer hard drives (and indeed bays) are not designed for hotswapping and it can cause damage (though maybe modern build quality is good enough that you'd be lucky most of the time). "Downtime" on your home server in your closet is a minor inconvenience at worst.

Re: Should I buy ECC memory? (2015)

#202
post #34
post #19

Earlier quoted context omitted.

I agree on gaming, but e-mail often contains important information that I wouldn't want to suffer from random corruption.

I don't understand why anyone would run their own email server. Cloud offerings work so well and are cheap.

Cloud offering here: we run ECC memory on all our servers, natch. It's not turtles quite all the way down.

Re: Should I buy ECC memory? (2015)

#203
post #201
post #199

Earlier quoted context omitted.

I hotswap drives all the time, it's not a problem and makes a harddrive swap a 30 second task instead of a 10 minute task and doesn't incur downtime either.

Most consumer hard drives (and indeed bays) are not designed for hotswapping and it can cause damage (though maybe modern build quality is good enough that you'd be lucky most of the time). "Downtime" on your home server in your closet is a minor inconvenience at worst.

I use NAS Harddrives which are built for hotswapping. I have no idea why anybody would use a consumer harddrive in a RAID Array, the price difference is 10€ at best AFAIK.

Re: Should I buy ECC memory? (2015)

#204
In the late nineties, the Intel desktop chipsets such as 440LX and 440BX offered ECC functionality, all you had to do was spend ten or fifteen bucks extra on the memory. Great hardware.

I'm unhappy that Intel made things more expensive and complicated with their market differentiation, but from their POV it was logical. PC users were screwing up the reliability of their systems in so many ways via overclocking, and were habituated to accept crappy reliability via pre-NT Windows. PC users could have demanded ECC and they didn't. I'm sure that even when the chipsets made it easy, only a tiny fraction bothered to use ECC.

Re: Should I buy ECC memory? (2015)

#205
post #203
post #201

Earlier quoted context omitted.

Most consumer hard drives (and indeed bays) are not designed for hotswapping and it can cause damage (though maybe modern build quality is good enough that you'd be lucky most of the time). "Downtime" on your home server in your closet is a minor inconvenience at worst.

I use NAS Harddrives which are built for hotswapping. I have no idea why anybody would use a consumer harddrive in a RAID Array, the price difference is 10€ at best AFAIK.

For a home server what's the benefit you're paying for though? I don't need max performance (I use RAID for redundancy rather than anything else), and a little downtime when I replace a disk isn't an issue.

Re: Should I buy ECC memory? (2015)

#206

Earlier quoted context omitted.

Fortunately the new AMD Ryzen processors support ECC in the memory controller, unfortunately none of the boards seem to be testing/certifying it yet and the UEFI on a lot of the boards is a mess right now. Hopefully more consumer boards support/certify it since it is already there on the memory controller.

The Asrock 370 boards officially support ECC, though I've read that various BIOS/UEFI versions don't: https://www.reddit.com/r/Amd/comments/655e7v/all_asrock_am4_... People are reporting that the Asrock 350 boards do too. Gigabyte lists some ECC modules on the compatibility list but some report that it isn't working right.

Good to know, I'm waiting for all of these boards to UEFI stuff to stabilize before I go shopping. Seems a bit messy right now.

Re: Should I buy ECC memory? (2015)

#208
post #55

Earlier quoted context omitted.

Google had done extensive studies[1]. There is roughly 3% chance of error in RAM per DIMM per year. That doesn't justify buying ECC if you have just one personal computer to worry about. However if you are in data center with 100K machines each with 8 DIMM, you are looking at about 6K machines experiencing RAM errors each day . Now if data is being replicated then these errors can propogate corrupted data in unpredic…

I have hit soft errors in every desktop machine that used ECC. Either I have bad luck, ECC causes the errors or third thing. I think ECC should be mandated for anything except toys and video players.

[deleted]

Re: Should I buy ECC memory? (2015)

#209

Earlier quoted context omitted.

How much more expensive is ECC ram? I don't have it and I've never experienced obvious issues, if it's a lot more expensive it's not really worth it for the once or twice the desktop will likely experience an actual issue

Should be about 1/8th more since it's just a 72-bit bus for carrying 64-bits data and 8-bits check. Or rather, your dimm will have 9 chips instead of 8. How they get you is Intel will sell you a xeon which is the exact same die as an i5 in a different package for more money.

It should be 1/8th more, plus a bit for the scrubber. But in practice ECC memory is "enterprise priced" so it's more like double.

Re: Should I buy ECC memory? (2015)

#210
post #97

Yes. Everybody reading this should use ECC RAM, and non-ECC RAM should be called "error-propagating RAM". Random bit flips aren't cool, and they happen regularly. Most computers that have ECC RAM can report whether errors happen. I see them at least once a year or so. For instance, here are 2 ECC-correctable memory errors that occurred just last month. Cosmic rays? Fukushima phantom? Who knows. You'll never know why…

I remember the one time I bought ECC memory, for a PII-400. It was only 512MB or so I think, but in the 12 years that server ran I saw a grand total of 1 corrected error in the logs. Given how much of a premium that ECC memory was it felt like a waste.
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