Here where I live I can get a 6TB serious HPE SSD for €1781.63 or a 4TB consumer grade unit for €671.88. For that amount of money, I can get a 3-drive RAID-1 of Hitachi 10TB disks or, better, a 2-drive RAID-1 (certainly not as fast as the HPE board) and keep the third disk in another machine and do backups there (because the reliability of an SSD means nothing if the data is erased).
So in the end the choice is SSDs if you need fast storage or hard drives if you need cheap(er) storage.
Even if SSDs were priced the same as hard drive you would need much more SATA ports on a machine to achieve a big storage capacity.
Why? There are 16TB SSDs u.2 SSDs on the market. That is comparable to top-of-the-line hard drives in terms of bytes per port and much, much better in terms of bytes per volume.
It's also virtually impossible to overheat an SSD. Samsung SSDs have critical temperatures above 90C. You won't reach this temperature just by operating the drive. The only way I've been able to make a Samsung SSD trip the critical temperature alarm was by pointing a paint-stripping air gun into the fan inlet of a machine while running an fio workload. HDDs by contrast are trivial to overheat, and are destroyed by doing it.
Which mode exactly are you referring to? Because the 983 DCTs (retail version of the PM983) that I have don't support features like NVMe APST, and idle at 3+ W (for the M.2 version, which is lower-power than the U.2 version).
> It's also virtually impossible to overheat an SSD.
Maybe in a properly designed rackmount enclosure with fans that never drop below 4k RPM. But in a more typical consumer case, enterprise U.2 drives will absolutely overheat, and I have the logs to prove it. (The Samsung drives you refer to are definitely better about this than the kind of U.2 drives that use 15mm thick cases and controllers with more than 8 channels—which I believe includes all U.2 drives with capacity in excess of 8TB.) Consumer cases that still have 3.5" bays tend to provide plenty of airflow for them, but that's not the case for 2.5" bays.
I can replicate this at home with a Samsung 970 PRO m.2 in an Intel NUC. It just will not overheat. The only thing I can do to make it shut down is to put blankets over the NUC in which case the CPU has gone PROCHOT anyway.
Bottom line, it seems to me that power and heat are advantages of SSD, not HDD. It seems like people buy HDD purely because of GB/$, which makes sense to me at scale but not at home. The care and management of hard drives, and their atrocious performance, seems to outweigh the price advantage. It's really hard to manage HDDs successfully and even if you are doing it perfectly, it still means you are replacing the HDD every 3-5 years. What a pain.
Neither HDDs nor SSDs will last forever.
It's as easy as sticking a pair of drives in a cheap NAS enclosure and listening for the warning alarm when SMART predicts failure or a drive fails.
I did have to replace the previous NAS after 5 years-- not because of failure, but because I needed more storage and wanted more performance. Otherwise it might have lasted quite a bit longer.
This isn't really true-- flash isn't really like DRAM; leakage currents tend to increase even if you don't reprogram things (and to properly fight leakage-related data corruption, you really need to periodically rewrite and do the erases that further compound dielectric breakdown). And it's especially not true of board-level assemblies, where capacitor failure and solder joints become important.
> A hard drive will wear out based on power-on hours and start/stop cycles, regardless of how much you use it.
Some failure modes look like this in SSDs, too. Studies have shown that SSD age is a much better predictor of failure probability than usage. Depending on how firmware handles things and the cell characteristics, -insufficient use- of a SSD can cause failure, too.
I mean, I did some work on firmware for early SSDs and error rate / lifetime analysis and I've had SSDs lose data in a drawer unused, but maybe you know better. Yes, SSDs are better than HDDs, but not as drastically so as one would think.
I <3 flash. But I also like having big dumb spinny disks. I'm rather glad I can have both.
If we take my case at home, I would need about 30 TB of total capacity to be at ease. Let's disregard my previous comment about backups of backups and go for "just" 60 TB total capacity.
Where I live I can only reliably source 14 TB hard disks at €400 a piece and 4 TB SATA SSDs for €550 (I didn't look at NVME since the number of ports possible on one machine is too small).
So I would need 5 disks for 2000€ or 15 SSDs for 8250€. Almost any motherboard comes with 6 SATA ports but for the SSDs I would need to add at least one PCI Express raid card to get more SATA ports.
FWIW I could buy the cheapest new car available in France for the same price as the SSDs (Dacia Sandero base model).