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I seek to use my 500GB NVMe SSD as pseudo-RAM for deep learning by increasing pagefile size. My RAM's 28GB, I seek 64GB+. From the limited info I could find on DDR4, this SSD appears to have 10% its read speed - excellent, and sufficient for my application.

Reading up on others doing the same, advice has been shifting from "SSD funeral" to "no longer bad" - yet I remain uncertain, especially for my application. One train epoch reads 64GB of data, but writes ~zero. The linked SSD boasts 1.2 Petabyte writes, but no specs on reads; I presume it's much greater, if at all relevant? Assuming equal, the SSD can handle 18,000+ epochs - which makes degradation a non-issue.

This said, what's the status on this matter now, in 2019?

(As a side question, is its 2,280 Gb/s data transfer rate spec a likely typo?)

OverLordGoldDragon
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2 Answers2

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2) 3,500 MB/s is more realistic than 2,280 Gb/s; that's the number they hang out front.

1) Writes stress the drive much more than reads, so if your app is very read-heavy, you just might get that 600 TB of writes out of the drive. I would watch the writes like a hawk, and if you ever get within 2 orders of magnitude within 600 TB written (that is to say, 6TBW), expect it to go boom, and get that warranty claim form handy.

This article points to degradation caused by reads which points to a need to rewrite every 100K reads, a task handled by the firmware in the SSD. As you stated in your second graf, that is much lesser than the writes.

You may also enjoy this thought-provoking review with lots of chewy numbers.

3) Of course, there's that idle power consumption ceiling of 30 Megawatts to contend with; have you considered moving to Grand Coulee Dam, or somewhere in the Tennessee Valley Authority?

idle power consumption ceiling of 30 Megawatt

K7AAY
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The number of reads are a non-issue, its generally writes that cause degradation - and SSDs are also more robust then originally believed (although when they do fail its often sudden and catastrophic).

2280 megabytes per second is entirely believable for nvme SSD. SATA based ones are a lot slower and 500 megabytes/sec would apply to those.

davidgo
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