Should I buy ECC memory? (2015)
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Should I buy ECC memory? (2015)
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Re: Should I buy ECC memory? (2015)
#2[deleted]
Re: Should I buy ECC memory? (2015)
#3Do you use ZFS? If yes then you should use ECC memory.
Do you have a use case where you would want your computer to alert you when the ram is failing? If yes then you should use ECC memory.
Otherwise it's a nicitey and probably not worth the money.
Re: Should I buy ECC memory? (2015)
#4"Fri, 27 Nov 2015 00:00:00 +0000"
Needs (2015) added to the Title I think.
Re: Should I buy ECC memory? (2015)
#5Yes.
Bit errors are uncommon and range from benign to crash.
Your storage has them, memory has them, network has them.
Non error correcting memory very significantly increases risk.
And this is the kind of risk you don't notice, until you do and when you do, it's often subtle, insidious, impossible to track down.
Servers absolutely. It's debatable on desktop, but we have huge RAM now. Might as well error correct. The bit error risk is small. Bigger RAM only adds to that possibility.
Re: Should I buy ECC memory? (2015)
#6The article makes no mention of single event upsets (SEUs). These occur randomly when cosmic rays can cause a bit flip anywhere in the chip. ECC is a good way to mitigate SEU effects.
Re: Should I buy ECC memory? (2015)
#7While I was at Google, someone asked one of the very early Googlers (I think it was Craig Silverstein, but it may've been Jeff Dean) what was the biggest mistake in their Google career, and they said "Not using ECC memory on early servers." If you look through the source code & postmortems from that era of Google, there are all sorts of nasty hacks and system design constraints that arose from the fact that you couldn't trust the bits that your RAM gave back to you.
It saved a few bucks in a time period where Google's hardware costs were rising rapidly, but the ripple-on effects on system design cost much more than that in lost engineer time. Data integrity is one engineering constraint that should be pushed as low down in the stack as is reasonably possible, because as you get higher up the stack, the potential causes of corrupted data multiple exponentially.
Re: Should I buy ECC memory? (2015)
#8[deleted]
Re: Should I buy ECC memory? (2015)
#9Depends on what you are doing.
ZFS storage servers: Hell yes
High-value data in my DB? Hell yes
email server: Nope
super cool gaming rig: Nope
* Cluster: Hell yes
General office workstation: maybe.
I don't have the budget for 20 redundant copies. I do have the budget for slightly more expensive RAM. Especially on my ZFS storage arrays.
ECC memory is like Insurance. You hope you never need it. One real downside that I have found, is finding out _when_ that memory correction has saved your ass. RAID arrays can alert you when a disk is dead. SMART mostly tells you when disks are failing. I haven't found a reliable tool to notify me when I am getting ECC errors/corrections.
Re: Should I buy ECC memory? (2015)
#10Do you use ZFS? If yes then you should use ECC memory. Do you have a use case where you would want your computer to alert you when the ram is failing? If yes then you should use ECC memory. Otherwise it's a nicitey and probably not worth the money.
Do you use ZFS? If no then you should use ECC memory.
Now the half truth becomes full-truth.