
Intel Optane DC Persistent Memory Operating Modes Explained - ssvss
https://itpeernetwork.intel.com/intel-optane-dc-persistent-memory-operating-modes/
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berbec
My question is why does it become volitile in memory mode? Is there some
different way of writing the data?

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kbuck
Since the module has both RAM and Optane storage on it, and only the Optane
storage is non-volatile, all memory writes would have to be written to the
Optane storage instead of the RAM before they could be treated as complete.
This would probably be significantly slower and would somewhat restrict how
cleverly the device could manage the RAM/Optane resources. (For example, with
the current architecture, if a memory region is being repeatedly rewritten, it
can just keep it on the RAM and not touch the backing Optane storage.)

It's also unlikely that this feature would be deemed useful given that they
already provide the App Direct interface; for a server (which appears to be
the intended market), if you've removed power from the memory, you're probably
intentionally rebooting the server and would prefer that it reboot cleanly
rather than have the random contents of the previous boot in memory.

