SSD Versus HDD For Computer Storage... Pros and Cons

[Bamax]

Arioch's computer woes made me reconsider my own laptop.

It has an HDD (Hard Disk Drive). Which means it is a mechanical disk which writes and reads over it's surface.


A computer store associate recommended I change the HDD to SDD (Solid State Drive) because they read and write faster than HDD.

SSDs write and read memory without moving parts.


I researched instead of blindly following the store associate's advice.

Here is what I found:

HDDs may be slower than SSDs due to their mechanical nature, but ironically they are likely to store information longer than SSDs.

SSDs tend to stop working before HDDs fail.

I have had my HDD for years (over four years) and I have never needed to worry about data loss beyond the mistakes I made.

Whereas SDD may have higher performance but is bound to bite the duster sooner than an HDD ever would. SDDs are also more stable during movement than an HDD (cellphones don't use HDD).

So there you have it. Those are my conclusions. Make of it what you will.

[spacewhale]

Newer computers support NVMe SSDs which absolutely dust older hard drives (consider a typical laptop hard drive, a Seagate Momentus, pushing around 60MB/sec read/write versus an average of 2500MB/sec read/write from a Samsung 980 Pro NVMe, it's such a spanking it's not even funny, though even a SATA SSD would give you ~500MB/sec read/write). You'd legitimately need a big RAID of hard disks just to keep up, and that still wouldn't give you as good random access performance. All data used by your computer is loaded into RAM from non-volatile storage, a hard drive is going to take way longer to do that, and your computer will be noticeably more responsive if you swap to a fast SSD. If you've got gigabit fiber, you'd practically be write bottlenecked with a laptop hard drive, considering you can download from the Internet faster than your computer could write to disk (assuming a laptop HD). NVMes are also dirt cheap now, you can get a 1tb gumstick NVMe SSD for around 100 bucks. Considering consumer hard drives last around 3-5 years (at least according to Backblaze), don't bank on a drive to last forever. As far as SSD reliability goes, there's a bunch of different types of technologies used in SSD, they aren't all equally (un)reliable. To state unequivocally that they all don't last as long as HDs is pure FUD. You could point out some famously unreliable hard drives just the same, i.e. IBM Deathstars, but not all hard drives are made the same. Hard drives are king if you need to store an absurd amount of data for fairly cheap (i.e. I use a bunch in a NAS box), but for your personal computers, there's no reason at all to not use an NVMe SSD if your machine is new enough to support them.

[Arioch]

SSD's by their very nature wear out over time and gradually lose capacity, but you don't normally lose data, and they don't normally crash the way HDD's can. And the performance difference is very significant. When I got the SSD for TALON after the HDD crashed, it was so much faster that it was almost like getting a new computer. I used the SSD for about six years, rather heavily, and never had a noticeable loss of capacity. It still works, though it's a little bit wobbly now, but that may well be a result of the wider system failures that TALON was experiencing.

I think that the ideal situation, which may not be an option for a laptop, is to have both an SSD for performance and a HDD for cheaper capacity. TALON had a USB HDD for backup, and the new system has both SSD and HDD (plus the USB backup).

[Bamax]

SSD's by their very nature wear out over time and gradually lose capacity, but you don't normally lose data, and they don't normally crash the way HDD's can. And the performance difference is very significant. When I got the SSD for TALON after the HDD crashed, it was so much faster that it was almost like getting a new computer. I used the SSD for about six years, rather heavily, and never had a noticeable loss of capacity. It still works, though it's a little bit wobbly now, but that may well be a result of the wider system failures that TALON was experiencing.

I think that the ideal situation, which may not be an option for a laptop, is to have both an SSD for performance and a HDD for cheaper capacity. TALON had a USB HDD for backup, and the new system has both SSD and HDD (plus the USB backup).

Glad to know your computer woes are solved.

I don't know what are the signs of SSD failure if there is no data loss.

I will say they must put in really impressive SSDs in cellphones since I am far more likely to have my data corrupted and unreadable on a computer HDD than my cell.

[spacewhale]

SSDs do have data loss, you're going to get bit rot (which will occur largely without your knowledge, silent data loss), errors with controllers, what-have-you, just not mechanical errors like hard drives, but both types of storage can most certainly fail catastrophically. If you've got a machine with multiple drives, you could set up your Linux distro with bootable ZFS (with at least one device mirrored) and you'll actually catch disk errors and bit rot whenever a scrub is run and it'll self-heal from the replica (the filesystem runs checksums on blocks of your data, and stores these away for reference, if something is corrupted, it'll replace whatever failed checksum with its corresponding replica block.)

[Arioch]

I don't know what are the signs of SSD failure if there is no data loss.

The nature of how NAND flash memory works means that there is a finite number of times that each individual data cell can be erased and rewritten. This sounds more alarming than it is, as the failure condition is on write, not read, so it shouldn't normally cause loss of data. The controller software just marks that cell as unavailable, and mitigates this wear through algorithms that spread data around the available cells, so it's not something you should normally notice. I don't know what's causing the problems that the TALON SSD is having, but I don't think it has anything to do with the NAND write cycle limitation.

While they don't have the same fundamental lifespan limitations, HDD's don't have a much longer functional lifespan than SSD's do in my experience (unless you're talking about some heavy-duty enterprise-level drives designed for long-term reliable storage). Any storage system experiences data corruption or bit loss, but that's what error correction systems are for. I think that every computer I've ever owned has had at least one catastrophic HDD failure. SSD's don't have read/write heads that can physically crash into the media destroying the entire drive; HDD's do.

[Bamax]

I don't know what are the signs of SSD failure if there is no data loss.

The nature of how NAND flash memory works means that there is a finite number of times that each individual data cell can be erased and rewritten. This sounds more alarming than it is, as the failure condition is on write, not read, so it shouldn't normally cause loss of data. The controller software just marks that cell as unavailable, and mitigates this wear through algorithms that spread data around the available cells, so it's not something you should normally notice. I don't know what's causing the problems that the TALON SSD is having, but I don't think it has anything to do with the NAND write cycle limitation.

While they don't have the same fundamental lifespan limitations, HDD's don't have a much longer functional lifespan than SSD's do in my experience (unless you're talking about some heavy-duty enterprise-level drives designed for long-term reliable storage). Any storage system experiences data corruption or bit loss, but that's what error correction systems are for. I think that every computer I've ever owned has had at least one catastrophic HDD failure. SSD's don't have read/write heads that can physically crash into the media destroying the entire drive; HDD's do.

On an unrelated note... I can safely assume Loroi computing loses much less... if any data compared to modern computing?

Maybe they still lose data, but have so much auto-back ups that it hardly matters unless the backups are also wrecked.

[Arioch]

On an unrelated note... I can safely assume Loroi computing loses much less... if any data compared to modern computing?

Maybe they still lose data, but have so much auto-back ups that it hardly matters unless the backups are also wrecked.

As data density increases and you get smaller and closer to the minimum possible size for data elements, quantum weirdness is going to make some kind of errors inevitable. But I imagine that the higher level systems manage this to the point where it's not something that the user needs to worry about.

We're not all that far from this point now.

[icekatze]

hi hi

In my desktop, I've got some terabyte SSDs for my OS, and programs that get used frequently, or require fast loading times. And I've got a multi terabyte HDD's for storage space. Old games, videos, music, etc. I've been using them for years and haven't noticed any problems.

If I was hosting a server that was constantly reading and writing files from multiple users all day every day, I might consider a server grade HDD, but for most people's home use, I don't think SSD wear is going to be a serious problem.

I don't know what the costs of different drives are for laptops, but an SSD does have the advantage of being impact resistant.

If I ever upgrade my home system, I'd be tempted to get a home server to store my files. That way I wouldn't have to worry about having a huge drive on all my devices, and I'd be able to easily work on art or writing on my laptop or my desktop. A friend of mine recently wired their house with multi-gig per second fiber, and I was astonished at how cheap it was.