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Comment by dekoruotas | Hacker News Reader

Very interesting. This longevity aspect frequently comes up in the Wii U modding community. It is tempting to plug in a simple USB stick to store the game files, but, because of the intense read/write nature, it is deemed to be prone to failure. Recently use of high-endurance SD cards has grown, but some say it is still not as safe as an external HDD. It would be interesting to hear thoughts from someone more experienced about the safest storage option as the last thing you want is for your save files to get corrupted.

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In the same vein as this I've wondered for a couple years now what the impact of flash storage longevity is on mobile phone performance over time. Felt like my Samsung S8 was very snappy when I got it, yet a couple years later things that used to be fast - like finding specific music, scrolling through the photos in my gallery, etc. - had slowed down considerably.

Could also just be software updates or other things causing this but there should be some component of decreasing performance caused by wear on flash storage.

The only part of a far future sci-fi that stayed with me is the use of memory chips as universal (ha) currency :ie capacity was face value and then total value was determined by the data contained on the chip and how much someone(thing) wanted that. Sometimes it looks like that is an inevitable outcome.

You're right, flash degradation and deterioration of write speeds is pretty much primary reason why older phones feel slow and laggy.

A lot of - especially older or mid/low range - phones have cheap eMMC storage which is signifcantly worse at wear leveling than the higher end UFS storage.

Could you get around this by using a custom ROM that installs the OS on a high-quality microSD card or something like that?

> phones have cheap eMMC storage which is signifcantly worse at wear leveling than the higher end UFS storage.

Which is shocking really - the phones should switch the eMMC to RAW flash mode (ie. no wear levelling), and then write an actually-smart wear levelling algorithm that runs in the OS.

The OS has far better info for wear levelling anyway - it has more visibility into read-write patterns, it has more RAM to store more state, it can cron background scrubs and reorganisation to idle periods, it can be patched if a bug is found which only manifests after years, etc.

Unfortunately, as far as I'm aware, most eMMC's can't be put into any kind of RAW mode anyway.

What kind of intense read/write nature you are talking about in a video game console? It just reads the game ROM from storage and executes it, there is nothing to write back, the game is not being modified in any way while playing. All these talks about wearing out sdcards in game consoles or raspberry pi devices in my personal opinion are partially because of people encountering poor quality cards - counterfeits. There is an sdcard in my car camcorder which must have seen thousands of full write cycles and still has no issues functioning despite all the operating temperature differences it endures due to weather seasons.

Writes should be minimal yeah. But reads could be intense. My car has worn out two maps SD cards. One of them had a questionable chain of custody, but I went back to the almost certainly original card that came with the car, and it's starting to misbehave in the same ways, so I think it's only a matter of time. These cards are unwritable after factory initialization, so writes are definitely not a factor.

I understand that reads can technically cause read disturb, but isn't this normally handled by the controller? My intuition says that the writes caused by block rewrites should not significantly accelerate wear. I'd suspect more mundane issues such as bad solder, but would love to hear an expert take.

Safe is a multifaceted term. Essentially these storage media (I'm more experienced with solid state but HDDs may be included) the probability the data you wrote is the data you read is a function of how many program/erase cycles, how long ago that was, and naturally the part's specifics. For example, a lot of NOR flash is rated to 10 years at up to 100k cycles. But devices > 10 years old rarely make the news for their flash being dead. On the other hand, I believe there was a Tesla fiasco where their logs were wearing out the flash prematurely.

There's usually trends to look for in regards to that third factor. The lower the # of bits per cell, the higher probability the voltage level is still working the right range. Which is why so much flash is still SLC or pSLC capable. Usually this is more industrial. Then you have entirely different technologies altogether. NVRAM/FRAM/MRAM are various terms for extremely high (or infinite) read/write technologies while still being non-volatile (keeps its data with power off). I don't know how much of a drop in replacement those are. I think LTT had one of those on a flash drive a while back https://youtu.be/oJ5fFph0AEM, but it's so low capacity it'll probably be useless.

It may be possible to hack something up with a MR5A16A. It's a whole 4 MB but has unlimited endurance and over 20 years of endurance. It looks like it has more of an SRAM interface than NAND, but should be capable of saturating a USB high speed link. The drive would likely cost $75? TBH if there was a market it may be a fun project.

If you sacrifice some endurance you can go up to 1Gb per device which might be interesting. But the cost scales.

> But devices > 10 years old rarely make the news for their flash being dead.

Accelerated stability testing is fraught with potential issues, and any output is intentionally conservative.

An issue with estimating lifespan on new products is that they'll expose them to more extreme conditions, but those more extreme conditions may trigger (exponentially faster) higher order reactions that are relative non-issues at regular conditions.

Then you have things like activation energy requirements for a reaction that just might not be met at regular conditions, but happen at higher temperatures.

And an IC is quite the soup of molecules in varying combinations unlike a straightforward solution.

and any output is intentionally conservative.

Samsung still screwed up with the planar TLC flash used in the infamous 840 EVO SSD, which had a real-world retention measured in months. Their "fix" was to issue a firmware update that continuously rewrites data in the background, but of course this has no effect if the drive isn't always powered.

https://forum.acelab.eu.com/viewtopic.php?t=8735

https://goughlui.com/2024/07/20/salvage-tested-an-elderly-fo...

I’ve run a modded Wii U for ~5 years (mocha cfw -> cbhc -> tiramisu -> aroma) and have always used a usb flash drive, but I did have one fail and just assumed it was a bad unit — I could well imagine the write patterns being particularly hard on them though.

Probably overkill, but I wonder if anyone has experimented with setting up a raspberry pi or something to pass through access to a network share over USB, that way you could have all the data on a RAID array with a proper automated backup strategy somewhere.

Considering SSD prices have crashed it’s the only way to go IMO, it solves literally all of the problems with other iptions like power draw for hard drives and longevity and speed over flash drives

Why is there that much writing? I would imagine a game system reads billions of times as much data as it write.

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