5 ms·

I am surprised that ECC is not more popular. RAM errors (SEUs) are common in every platform. One hacker that I worked with almost a decade ago did this BlackH

I am surprised that ECC is not more popular. RAM errors (SEUs) are common in every platform. One hacker that I worked with almost a decade ago did this BlackHat presentation with some analysis that correlates errors with increased temperature (by geo-locating clients of "bit squatting"). I put together a new SuperMicro server a few months ago and went with 256GB of ECC. Yeah it's very expensive, but it's absolutely worth it if you care about the integrity of your data. See: https://media.blackhat.com/bh-us-11/Dinaburg/BH_US_11_Dinaburg_Bitsquatting_WP.pdf https://media.blackhat.com/bh-us-11/Dinaburg/BH_US_11_Dinabu... Where are you now Artem?

jeffbee 6y ago
It's not even that expensive. An 16GB "server" DIMM costs what, $65 at retail? Apple will charge you $200 for 8GB of non-ECC. The real cost on ECC memory is getting a CPU and platform that support it properly.
- anonymousiam 6y ago
  Four of these weren't cheap. ($1,441.36) https://www.amazon.com/gp/product/B07YF249FX https://www.amazon.com/gp/product/B07YF249FX
- Dylan16807 6y ago
  > An 16GB "server" DIMM costs what, $65 at retail? Clocked at 2400MHz, sure. I can't find a single non-sketchy listing for even 3200MHz unbuffered ECC memory, let alone the 3600MHz you want for current Ryzen chips. And those are just the speeds at reasonable prices, ignoring the 4000-5000 range. At least DDR5 should improve things.
  - theevilsharpie 6y ago
    > I can't find a single non-sketchy listing for even 3200MHz unbuffered ECC memory https://www.crucial.com/memory/server-ddr4/mta18adf2g72az-3g2e1 https://www.crucial.com/memory/server-ddr4/mta18adf2g72az-3g... > let alone the 3600MHz you want for current Ryzen chips Current DDR4 JEDEC-approved speeds top out at DDR4-3200. Anything beyond that is technically overclocking, even if it's overclocked from the factory and marketed to run at those speeds. Assuming that your platform supports overclocking DRAM, you can also run DDR4-3200 ECC memory at 3600 MT/s, if you feel that the performance uplift is worth the risk of stability issues.
    - vbezhenar 6y ago
      And the good thing is that you’ll know immediately about stability issues with ECC.
      - jeffbee 6y ago
        Patrol scrubbing is a RAS feature of only more expensive platforms. On most hosts you are likely to learn about the issue only at the time some program tries to access the marginal page or row.
        theevilsharpie 6y ago
        > Patrol scrubbing is a RAS feature of only more expensive platforms. All of the ECC-capable platforms I've used (including my AMD-based desktop PCs) have supported patrol scrubbing. What have you used that doesn't?
        jeffbee 6y ago
        My AM4 motherboard doesn't offer any options for scrubbing and its manual is vague about whether ECC errors will even be reported to the operating system. By contrast my HPE ProLiant DL360 has firmware settings for scrubbing and I know the event reporting works because I see it in the logs all the time.
        theevilsharpie 6y ago
        The operating system will explicitly tell you at runtime if ECC support is available. If this returns an affirmative value, then ECC is working. Support for patrol scrubbing is a bit more variable. It's supported in my ASRock motherboard (B450M Pro4). It was also supported in two previous ASUS motherboards (AMD AM2 and AM3 platforms, respectively), although they called it something else that I can't remember. As well, a lack of a setting for patrol scrubbing doesn't necessarily mean that it's unavailable; it could just be enabled but not user-configurable.
  - jeffbee 6y ago
    I thought we were talking about correctness, not going shopping for more-error-prone DIMMs.
    - Dylan16807 6y ago
      Well I thought we were talking about getting ECC without major tradeoffs, to understand its [lack of] popularity. And I wouldn't say faster memory is necessarily more error prone. But it doesn't really matter, because non-ECC products have to have extremely low error rates to be viable. Even if a speed is at the high end of "extremely low", once you add ECC you'll have an exceptionally solid component.
      - theevilsharpie 6y ago
        > Well I thought we were talking about getting ECC without major tradeoffs, to understand its [lack of] popularity. ECC isn't popular on desktops because Intel, which supplies the overwhelming majority of the processors for platforms that use DIMMs, doesn't support ECC at all. As such, the market for people who can actually use ECC in a desktop (much less would want to) is very small. The only reason unbuffered ECC DIMMs are even on the market at all is because low-end servers use them.
        faxfax 6y ago
        I'm not sure where everyone gets the idea that Intel charges a big premium for ECC platforms. If you buy the low-end workstation Xeons the processor costs about the same. For example, Xeon W-1290 (10C, 5.2GHz turbo) has a $494 MSRP. The i9-10850K (also 10C, 5.2GHz turbo) has a $453 MSRP. You also have to buy a motherboard with a workstation chipset to use the Xeon, but W480 chipset motherboards are also priced about the same (~$200) as their consumer Z490 counterparts. The real reason ECC is not common is because it is perceived as unnecessary for desktop workloads. Software crashes and corrupts data all the time because of bugs, not bitflips. Most consumers care so little about their data that a single hard drive crash will wipe it all out anyways. Why spend 12% extra on memory if consumers hardly see any value from it?

jeffbee 6y ago

It's not even that expensive. An 16GB "server" DIMM costs what, $65 at retail? Apple will charge you $200 for 8GB of non-ECC. The real cost on ECC memory is getting a CPU and platform that support it properly.

anonymousiam 6y ago
Four of these weren't cheap. ($1,441.36) https://www.amazon.com/gp/product/B07YF249FX https://www.amazon.com/gp/product/B07YF249FX
Dylan16807 6y ago
> An 16GB "server" DIMM costs what, $65 at retail? Clocked at 2400MHz, sure. I can't find a single non-sketchy listing for even 3200MHz unbuffered ECC memory, let alone the 3600MHz you want for current Ryzen chips. And those are just the speeds at reasonable prices, ignoring the 4000-5000 range. At least DDR5 should improve things.
- theevilsharpie 6y ago
  > I can't find a single non-sketchy listing for even 3200MHz unbuffered ECC memory https://www.crucial.com/memory/server-ddr4/mta18adf2g72az-3g2e1 https://www.crucial.com/memory/server-ddr4/mta18adf2g72az-3g... > let alone the 3600MHz you want for current Ryzen chips Current DDR4 JEDEC-approved speeds top out at DDR4-3200. Anything beyond that is technically overclocking, even if it's overclocked from the factory and marketed to run at those speeds. Assuming that your platform supports overclocking DRAM, you can also run DDR4-3200 ECC memory at 3600 MT/s, if you feel that the performance uplift is worth the risk of stability issues.
  - vbezhenar 6y ago
    And the good thing is that you’ll know immediately about stability issues with ECC.
    - jeffbee 6y ago
      Patrol scrubbing is a RAS feature of only more expensive platforms. On most hosts you are likely to learn about the issue only at the time some program tries to access the marginal page or row.
      - theevilsharpie 6y ago
        > Patrol scrubbing is a RAS feature of only more expensive platforms. All of the ECC-capable platforms I've used (including my AMD-based desktop PCs) have supported patrol scrubbing. What have you used that doesn't?
        jeffbee 6y ago
        My AM4 motherboard doesn't offer any options for scrubbing and its manual is vague about whether ECC errors will even be reported to the operating system. By contrast my HPE ProLiant DL360 has firmware settings for scrubbing and I know the event reporting works because I see it in the logs all the time.
        theevilsharpie 6y ago
        The operating system will explicitly tell you at runtime if ECC support is available. If this returns an affirmative value, then ECC is working. Support for patrol scrubbing is a bit more variable. It's supported in my ASRock motherboard (B450M Pro4). It was also supported in two previous ASUS motherboards (AMD AM2 and AM3 platforms, respectively), although they called it something else that I can't remember. As well, a lack of a setting for patrol scrubbing doesn't necessarily mean that it's unavailable; it could just be enabled but not user-configurable.
- jeffbee 6y ago
  I thought we were talking about correctness, not going shopping for more-error-prone DIMMs.
  - Dylan16807 6y ago
    Well I thought we were talking about getting ECC without major tradeoffs, to understand its [lack of] popularity. And I wouldn't say faster memory is necessarily more error prone. But it doesn't really matter, because non-ECC products have to have extremely low error rates to be viable. Even if a speed is at the high end of "extremely low", once you add ECC you'll have an exceptionally solid component.
    - theevilsharpie 6y ago
      > Well I thought we were talking about getting ECC without major tradeoffs, to understand its [lack of] popularity. ECC isn't popular on desktops because Intel, which supplies the overwhelming majority of the processors for platforms that use DIMMs, doesn't support ECC at all. As such, the market for people who can actually use ECC in a desktop (much less would want to) is very small. The only reason unbuffered ECC DIMMs are even on the market at all is because low-end servers use them.
      - faxfax 6y ago
        I'm not sure where everyone gets the idea that Intel charges a big premium for ECC platforms. If you buy the low-end workstation Xeons the processor costs about the same. For example, Xeon W-1290 (10C, 5.2GHz turbo) has a $494 MSRP. The i9-10850K (also 10C, 5.2GHz turbo) has a $453 MSRP. You also have to buy a motherboard with a workstation chipset to use the Xeon, but W480 chipset motherboards are also priced about the same (~$200) as their consumer Z490 counterparts. The real reason ECC is not common is because it is perceived as unnecessary for desktop workloads. Software crashes and corrupts data all the time because of bugs, not bitflips. Most consumers care so little about their data that a single hard drive crash will wipe it all out anyways. Why spend 12% extra on memory if consumers hardly see any value from it?