The Evolution of Disk Storage and an Introduction to NVMe

[sliken]

My dad had a 256bit memory module on his desk. Made out of sandwich of two pieces of glass and 16 vertical and 12 horizontal wires. Each intersection had a small ferrous ring.

Around that time he was programming and early computer and you could actually hear the memory bits changing. He was excited listening to it, figuring each click was a loop. Then her heard a different sound and realized he as hearing instructions and not loops.

[jcoffland]

Some really early computers stored bits in waves in mercury. A series of waves would be started at one end of a tube full of mercury and they would be read back when they arrived at the other end. The memory of course then had to be refreshed. Core memory was however much more successful.

https://en.m.wikipedia.org/wiki/Delay_line_memory

[agumonkey]

Same idea was used between satellite and ground, wave was used as a memory that could be reused when back to station.

[Avery3R]

An example of delay line memory using a wire that vibrates: https://www.youtube.com/watch?v=2BIx2x-Q2fE

[spectramax]

I am surprised the article doesn't talk about Optane technology: https://en.wikipedia.org/wiki/3D_XPoint

[Nursie]

Is Optane really 'all that' compared to other PCIe storage?

I know that Intel are positioning it as some sort of system accelerator, and I know it does tend to score well in comparisons... but not "This is in a completely different category" well, AFAICT.

What's special about it compared to, for instance, Samsung's NVMe offerings?

[chapium]

Why is Optane storage always referred to as "Optane technology" (big announcer voice)?

[edoo]

I use LVM and have enough storage that all SSD would be a little expensive so for the last few years I've been using the block caching LVM feature with mirrored NVME drives as a writeback cache to my large HDD array. It greatly increases the performance of the storage with little hassle.

If haven't played with gluster for a few years but it has a tiered storage feature so the most recently used files actually get moved onto the high speed storage medium, which depending on your workloads might be even better, assuming gluster is now performent and stable enough.

[ntw1103]

I recently upgraded my laptop to a Thinkpad T470s, which supports M.2 NVMe, and M.2 Sata. I upgraded from a 500gb NVMe drive to a 1TB M.2 sata drive. Why do I say upgraded if it is slower? Well, in a laptop, power usage is hugely important, as is heat. To prevent throttling on the CPU, less heat is better. I did a lot of research, and found that the sata based M.2 drives consume less power, and generate less heat. For my purposes the sata speed is sufficient. :)

[brianpaul]

FWIW, I believe Cray had an SSD option for the X-MP back in the early 80s.

[wolf550e]

From the brochure, it had a few million of 64-bit words worth of RAM that was used as regular RAM ("central memory") and a lot more of ECC DRAM that was used as fast storage ("SSD"). What was the API for the SSD? Was it mapped into virtual memory as RAM, or did the ISA have I/O in,out opcodes for it with word address, or did it use the API for disk storage, or what?

[theideaofcoffee]

They sure did! It came in 256-, 512- and 1024-MB flavors, if i recall, in its own cabinet off to the side at a blazing 1000MB/s.

I don’t have a hunk of the SSD, but I have a (30lb) board of the central memory perched against my desk right now.

[sliken]

Register latency is usually around 4ns (2.5-3.5 Ghz with a pipeline depth of 12-16). The article claims main memory latency is 7x more, which is around 24ns to 45ns. I tried to come up with plausible numbers that fix the 7x ratio they mention.

These days main memory latencies are more around 70-80ns (single sockets) and 80-100 ns (dual sockets).

Being off by so much does make me wonder about the accuracy of the rest of the article.

[3xblah]

Will the expression "spin up" ever fall out of usage?

[tyingq]

It was in wide use for jet and turbine engines, centrifuges, gyroscopes, etc, before disk drives. I don't think it will fade away.

[bluedino]

We 'spin up' virtual machines or instances now

[modzu]

language is symbolic so there doesn't have to be a literal connection between the reference and referent. for example you still "boot" a computer, which comes from the concept of "bootstrapping", ie, pulling oneself up by the straps of their boots. no boots are involved.

[NikolaeVarius]

Doubt it, though I don't think that I've used it in the context of SDD's recently since latency is that low.

I think colloquially, it's pretty much understood to mean "time between turning on and being useful"

[niccl]

At least one of the D's in the acronym usually means Disk, and there isn't a disk in many of these. Will that ever go, do you think?

[jyrkesh]

Contrary to what others said, it will likely fall out of favor the way the floppy icon faded for "Save" functionality in GUIs. It's everywhere until one day you realize you can't find it in any of the apps you use every day.