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Comment by cglan | Hacker News Reader

I will say, SSD pricing is pretty frustrating. There's a lot of focus on faster and faster nvme that's barely noticeable while actual capacity has really stagnated at around 2-4tb. As someone who is very into photography, it takes not very long to fill 2tb of space. If I could buy a cheap 16tb ssd with fast reads and slow writes I'd be a happy camper but it doesn't exist unless I want to buy spinning disks (I don't)

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Yeah, I'd gladly take a cheap large capacity SSD that can only do 500MB/s for storing data. It's still gonna be much faster, quieter and cooler than a HDD.

Looking at the prices, they have barely gone down at all in the last 3 years (for the same specs). And the best price per capacity is still at 1TB.

Some of that is probably covid supply shortages. SSDs have controllers, and controllers have chips.

The prices kinda look like they are going down a tiny bit, and thats because companies keep introducing ssd’s without dram cache. One those are halfway full their writes are maybe 3/4 fast as a hdd and they might last for 2-3 years

I had big hopes for Samsung’s QVO line but they’ve barely done anything with it. They’re often not much cheaper than EVO. And the 8TB drive is almost £200 more expensive than 20TB of spinning rust. I could get 30TB+ storage for the same money.

Have you looked at something like Intel 660p? They're pretty crappy as SSDs go, but they're quite cheap (by about 40% compared to what I would put into my desktop, at least where I live).

Largest size is only 2 TB, and they aren’t cheaper than e.g. Samsung QVO, as far as I can see.

The Intel 660p is a higher-tier product than Samsung QVO drives. Both use QLC, but the Intel drives are NVMe and thus have much higher peak performance (when operating out of the SLC cache). But Intel wasn't interested in pursuing the niche of users who wanted more than 2TB in a consumer drive.

Yes, but the topic was about QVO drives still being too expensive in terms of $/TB. The Intel drives don’t really help in that respect.

I wouldnt touch Intel SSD. They ship documentation stating read-only failure mode in case of reaching end of life/defects. In a big endurance test some time ago Intel drive simply died and vanished from the system on reboot, followed up by Intel mouthpiece claiming _this is by design_.

https://techreport.com/review/26523/the-ssd-endurance-experi...

"After a reboot, the SSD disappeared completely from the Intel software. It was still detected by the storage driver, but only as an inaccessible, 0GB SATA device.

According to Intel, this end-of-life behavior generally matches what’s supposed to happen. The write errors suggest the 335 Series had entered read-only mode. When the power is cycled in this state, a sort of self-destruct mechanism is triggered, rendering the drive unresponsive. "

That article is nearly 10 years old.

Intel bribe scandal was 20 years ago, and they still do it after tweaking (clients receive free hardware instead of straight $) to not be so blatantly illegal. "Cripple AMD" ICC/MKL was 13 years ago yet "Arc 380 drivers do not support ReBar on AMD's Ryzen CPUs, the functionality only works with this technology on Intel's own processors."

They were going for around 70 dollars for a tb on newegg before prime day. You might want to be on the lookout.

Once the SLC cache is exhausted on a drive like the 660p, sustained writes drop to below 100MBs

That makes sense considering that QLC (2^4 charge levels) only stores 33% more data per cell than TLC (2^3 charge levels). Therefore at best it can only be 33% cheaper/bigger.

QLC is 2x TLC (16/8=2).

Quad bits to triple bits is 4/3=1.33. Taking your way of counting to the extreme: if I have a cell that can handle 1 million bits, I can't just add an extra bit of storage for another 1 million bits of storage. I have to actually add the full megabit of storage.

Yes, you are right. I mixed it up with the change from SLC to MLC where 1 extra bit was double the density.

Why you need SSD for photography? An HD seems a better solution to be honest, isn't?

Opening a single picture is a sequential operation, as well as dumping pictures from camera to disk.

Am I missing something obvious?

>Opening a single picture is a sequential operation

Exactly what i was thinking!

Not the person you replied to, but bulk exports from something like Lightroom or Capture One benefit from faster speeds. If you have a fast enough CPU and enough memory, the main bottleneck is I/O. It doesn't matter for a few photos, but when you want to (for example) convert a whole trip worth of processed raws to JPG, every MB/sec counts.

Laptops tend to not have HDD slots anymore.

Raw photos are 30-100MB in size. Going through your shots on an HDD is excruciatingly slow.

Most technology seems to chase weird benchmark numbers as it seems the market decides as such. It was mhz to ghz through 2010, then it was cores, then these SSD numbers, or the refresh rates.

Most of it seems absurd to the majority of users, even if you could subtract the placebo effect.

Silly question - what makes you dislike buying four 4tb SSDs compared to buying one 16tb SSD? I could see it being less portable to have multiple drives, but I would presume that 16 TB isn’t really something that needs to be brought around portably unless you’re going somewhere for extended period of time without internet (preventing the use of a NAS/cloud storage). Multiple SSDs also allows the use of RAID for increasing speed and/or susceptibility of failure.

if you are moving that data around, nas/cloud storage can be super frustrating. copying 16tb of data over usb3/c is much faster than 100mbps or 200mbps internet.

That’s definitely valid for cloud on the public internet, but how fast can you pull local data on LAN?

If one SSD has a failure rate of 5%, 4 SSDs will have a failure rate of 18.6%. If the 4 devices are in a RAID0 for convenience (don't have to figure out where to put files), there is an 18.6% chance of losing all data vs 5% with a 16TB drive. You can use RAID5/6 to mitigate the risk but then lose capacity.

IMO, higher SSD speeds are not a target for improvement by manufacturers, but a side-effect of using higher-density chips, which is more cost-effective. They probably can't make a slow, high-capacity SSD economically.

> If one SSD has a failure rate of 5%, 4 SSDs will have a failure rate of 18.6%

That doesn't make sense, the probability that all 4 SSDs will simultaneously fail at any given moment, assuming a uniform distribution, is p(0.05)^4.

You don't need all 4 to fail, you need one, assuming no redundancy, but then you are sacrificing space, thus requiring you to buy even more drives.

If only one drive fails why would you lose all your data?

We're trying to avoid losing any data here.

So we desperately need a parity drive, which will bring the odds of data loss down to 2.3% for 4+1. (Though there are other factors that significantly complicate these odds.)

The point is to not lose any data. In the example, if you need 4 drives to store 16 TB of data instead of 1, your probability of data loss is 18.6% vs 5%.

How do you get 18.6%?

Prob of no failure in 1 drive is 95%. Prob of no failure in 4 drives is .95^4 = .816. Prob of failure in any of 4 drives is 1-.816 = 18.6%

Disclaimer: I got a D in Probability & Statistics

In theory but not necessarily in practice (see the 40k hr SSD firmware bug that recently took out HN)

I have a Canon R5, and i ended up with almost 800gb of storage in 8k raw, for a concert I did. I didn't even take that many videos as the camera overheated.

But a 4:20 video was 77gb. I have a 8bay(5 disks in raid 5) nas, but the performance isn't so good. Not good enough to edit, I use the 1tb nvme I have, but lots of swapping when I need to edit.

AFAICT this has been documented quite well. Use a SSD as cache. Easy to do with ZFS. The one I use on my NAS is one TB, it cost 200 EUR. It has the benefit of not causing data loss at power loss.

I suspect the reason is due to high base costs. Throwing on more dram chips and a better controller probably don’t cost much, but drastically effect performance. So, the cost savings of a simplified drive may only be a few dollars.

There's a good chunk of price to performance tradeoff. Taking samsung as an example, currently their lower end is $95/TB and their higher end is $125/TB. WD currently has a cheap QLC for $75/TB and a gen4 drive for $140/TB.

This is looking mostly around the 2TB range, and mostly M.2

It's hard to physically fit large amounts onto an M.2, but a 2.5 inch SATA drive would hold a big pile of QLC flash just fine.

I suppose the SATA bottleneck just looks bad. Maybe if we had better consumer support for 2.5 inch drives with NVMe then companies would be more willing to make that size.

I'm curious, do you not buy spinning disks due to the risk of failure?

Not OP, but for me the main reason would be travel. A SSD is much easier to carry as an external drive together with a laptop.

why don't you want to buy spinning disks

Well, for me it's noise, power/heat and shock resistance (in laptops). And these have also indirect negative consequences. For example, an external 3.5" HDD needs an additional power supply and cable in addition to the data cable, which is cumbersome and reduces portability.

Not the op, but I've just switched away from spinning disks recently. Kinda.

I have a NAS of 4x 8TB WD Red Pro; and a a desktop with 4x1 TB of nvME and 1TB of (grandfathered) SATA SSD.

For batch photo processing (i.e. lightroom) spinning disk is really sub-optimal. I'd rather have a 256GB or 512GB nvme and process batch by batch (and then offload to NAS), then a 8TB 7200 RPM HDD with all my photos.

To OPs point - depending on shooting style, you might easily do 300GB+ over a single wedding (primary + secondary shooter, 2 cameras each, 46MP, 14-bit uncompressed, spray-and-pray style).

I've heard but don't know if its true that SSD storage can constantly suffer data corruption if its not powered. It needs power to keep refreshing stored data.

Something that maybe spinning disks don't suffer from.

I don't believe SSD loses data over arbitrarily short periods of time such as days/weeks.

On the other hand, I would not trust either medium over extended period of time (years) personally - either dump to tape/optical, or keep making copies :).

Either way, I currently do not have a use case where either my SSDs or HDDs would be off for year or more.

(I do have a set of "off site" HDDs with my family which do stay unpowered for months before being exchanged)

Earthquakes.

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