[oh_sigh]

Why can't we just put a battery onto DRAM that maintains state if the power goes out, and be done with it?

[steve19]

That is how storage worked on PDAs back in the day with volitile memory. Let's the batteries completely die or change them incorrectly and you lost your data. Let's not go back to those days!

[wmf]

DRAM is not that dense; you can fit 128 GB of DRAM or 512 GB of XPoint on a DIMM. XPoint is also supposed to be cheaper than DRAM.

[hetman]

Because the power consumption to keep DRAM refreshed is fairly high so you'd need a pretty big battery, and because it would still be more expensive than 3DXP. It's just not practical for most use cases.

[amelius]

I figured that, but can we have some numbers here?

[ggm]

We do on RAID cards. It has limits.

-G

[jcoffland]

Battery backed DRAMM has been around for a decade or more.

[IshKebab]

You mean like suspend-to-RAM?