
Memory-Like Storage Means File Systems Must Change - Katydid
https://www.nextplatform.com/2017/05/24/memory-like-storage-means-file-systems-must-change/
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cryptonector
> “You have got this great big thickness of software that is between you and
> the hardware, and these new technologies, and 3D XPoint is the exemplary,
> forced me to see that everything has got to change,” explains [Eric] Barton.
> ...

Absolutely. With long latencies you can do all sorts of complex things.

The thing I really don't want to give up on is COW, but with COW writes get
multiplied, so it may be an unaffordable luxury, even with write-ahead
logging. One might log undo and redo logs and then write the rest lazily in-
place -- that too gets some write magnification, but less so.

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cryptonector
We were talking about this just days ago:
[https://news.ycombinator.com/item?id=14386626](https://news.ycombinator.com/item?id=14386626)
(not that we're done, just merely providing a link for others)

~~~
beagle3
Especially Howard Chu's (hyc_symas) comment, currently the top rated one.

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FrozenVoid
3Dxpoint is essentially a faster flash with all the problems of NAND cells.
Its not memory-like with limited write endurance.

>While Intel claims the new non-volatile storage medium will offer significant
improvements in endurance, performance, and power consumption (10x lower
latency, 3x write endurance, 4x more writes per second, and as little as 30%
the power consumption as competing NAND flash)
[https://www.extremetech.com/computing/237817-first-intel-
opt...](https://www.extremetech.com/computing/237817-first-intel-optane-
hardware-could-be-coming-to-consumer-desktops) >3D XPoint memory has better
endurance than NAND flash, but not enough to get away without wear levelling
[http://www.anandtech.com/show/11209/intel-optane-ssd-
dc-p480...](http://www.anandtech.com/show/11209/intel-optane-ssd-
dc-p4800x-review-a-deep-dive-into-3d-xpoint-enterprise-performance)

~~~
lodi
It's "memory-like" because it's byte-addressable. Flash forces you to read a
whole page to read a single byte.

~~~
FrozenVoid
Normal RAM also forces you to read the page to L1/L2 cache. Is RAM not byte-
addressable? See
[https://en.wikipedia.org/wiki/Cache_prefetching](https://en.wikipedia.org/wiki/Cache_prefetching)

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tutanchamun
(ST-) MRAM sounds much beter than 3D Xpoint to a layman like me (speed and
endurance like DRAM, so better than Xpoint), and seems to ship already from a
small company, why is Xpoint the focus? Better marketing?

~~~
cestith
The guy is leaving Intel, which was working on Xpoint during his employment
there. Regardless of the relative merits, he likely had far more exposure as a
file systems guy at Intel to storage technology being developed and sold by
Intel.

