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zozbot234today at 7:24 AM1 replyview on HN

> For a given capacity of memory, Flash uses far less power than DRAM, especially when used mostly for reads.

Flash has no idle power being non-volatile (whereas DRAM has refresh) but active power for reading a constantly-sized block is significantly larger for Flash. You can still use Flash profitably, but only for rather sparse and/or low-intensity reads. That probably fits things like MoE layers if the MoE is sparse enough.

Also, you can't really use flash memory (especially soldered-in HBF) for ephemeral data like the KV context for a single inference, it wears out way too quickly.


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adrian_btoday at 8:09 AM

Modern flash memory, with multi-bit cells, indeed requires more power for reading than DRAM, for the same amount of data.

However, for old-style 1-bit per cell flash memory I do not see any reason for differences in power consumption for reading.

Different array designs and sense amplifier designs and CMOS fabrication processes can result in different power consumptions, but similar techniques can be applied to both kinds of memories for reducing the power consumption.

Of course, storing only 1 bit per cell instead of 3 or 4 reduces a lot the density and cost advantages of flash memory, but what remains may still be enough for what inference needs.

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