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Comment by freitzkriesler | Hacker News Reader

Silly question, do we have to worry about older PC OSes not playing well with SSDs with excessive read/writes? I'd be concerned about destroying drives in short order with swaps that are miss behaving.

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You really have to go nuts with the writes to break a modern SSD. I don't think the bandwidth is even high enough to do so on purpose on a older machine.

Repeated defrag runs could wear some grooves into those bits. Older versions of Windows will not look for (nor care about) the "rotational" flag.

Disable defrag

I don't want to, watching the mishmash of rectangles slowly getting organized by color makes me feel very productive!

Only Vista has automatically-scheduled background full defragmentation and doesn't care about the rotational flag.

Then we're good, because nobody is going to install that friggin OS

Automatic defrag should only hit a handful of files each time it runs. You're not going to upset an SSD with that.

But even a whole-disk rewrite cycle will have very limited effect on the vast majority of SSDs.

I was astonished at the remaining life on a Samsung 960 pro when I checked the other day. I don't think I will have to replace it this decade at the current pace.

I have a pair of crucial mx500 ssds that are down to their last 10% of reported life... Awaiting the day they finally decide to stop working, maybe some time during the summer...

Older software tends to do far less 'background' stuff.

Whenever I run old OS's in virtualbox, I'm surprised that even doing lots of stuff for a week rarely results in more than a few GB's of writes.

So I don't think your concern is an issue for the typical case in practice. Obviously there'll be corner cases, but I haven't hit those yet.

Yes, we do have to worry about excessive writes.

I had a Samsung SSD - chosen because Samsung flash storage is generally better than most - connected to a SATA to IDE adapter, which was connected to an IDE to SCSI adapter, installed in a VAXStation 4000/30 (AKA the VAXStation VLC). It has 24 megs of memory.

https://twitter.com/AnachronistJohn/status/12947258190387527...

In less than a year, the SSD was dead, and I'm sure the reason was that I was compiling constantly on that machine, so writes to swap were constant.

I now have a spinning rust 500 gig SATA drive, and it has been fine for the last three years without problems.

Lack of OS-level TRIM support will slow down writes. TRIM also allows SSDs to maintain wear leveling.

Today the SSD microcontroller will do TRIM by itself.

Do you mean that it will automatically TRIM a block of all zeros? Or that it will itself try to parse filesystem structures and TRIM blocks that it can imply are un-used?

Can you list even one drive that internally parses filesystem data and guesses empty space to trim?

The trick I've heard to use SSDs on devices without TRIM is to just leave like 15% of the drive unprovisioned (i.e. create a single partition smaller than the drive) to give the drive's built-in garbage collection plenty of slack space to work with.

If you're working with vintage machines they all have drive size limits in the 2-8 GB range anyway so you'll end up doing that anyway as you can't get SSDs that small

You can't just leave the space unprovisioned in general. It's a crapshoot weather the drive will automatically over-provision using the unprovisioned space. I've never personally seen one that does this. With samsung, crucial, and other major brands you need to use their proprietary tools to change the over-provisioning percentage (before doing any formatting/creating partition table).

So, to anyone else trying this, make sure to do it before you create the partition table.

You get lots of benefit from permanently-trimmed space that is never used, even if it isn't explicitly "over-provisioned".

The underlying storage always has lots of free space, and thus is likely to have A) lots of pre-erased pages, and thus B) doesn't need to relocate as much stuff often to make contiguous chunks to erase, and thus C) write amplification is much lower.

Completely anecdotal observation with n=1 but FWIW I was an early adopter of SSDs and put one in my thinkpad in college running Win XP (this was before trim and all that) - it did require my to "align the partitions" but once that was done I did all my project work and would routinely hybernate my laptop. It lasted all through college and years after. I eventually just retired the device. SDD was fine. At the time SSDs were "unusable" for desktop workloads because of their perceived failure rates.

Whether or not they were rated for it, SSDs of that era were capable of vastly more writes than today’s SSDs

Early SSDs were all SLC with 50-100K erase cycles. Current cheap flash is around 200-500 cycles.

I was a college student so I couldn't afford one of those - I had a 100 GB SATA MLC SSD that read at like 100 MB/s - this was ~2007ish when SSD were still new from a consumer perspective.

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