A while back, when I started exploring using OpenHab at home, there were many discussions about hardware configuration (e.g. Raspberry PI) and whether uSD cards were reliable. @mstormi made a clear point that the SD cards are never reliable and one is to look for alternate options to house OpenHab’s Operating System.
I was new at all of this, I’ve been using SD cards for a very long time, and I never had any issues with them … until yesterday. I have 7 WyzeCams and all of them equipped with SanDisk Extreme Plus cards (32-128 GB). Those cameras have been running for a bit over 2 years. Yesterday, I wanted to copy some of the files, and 2 of such cards were defective. My PC would no longer recognize them, even after trying to reformat them with specialized tools.
My main message here is as follows: You’re going to invest quite a bit of time getting OpenHab to work. The last thing you want/need is a faulty SD card after all the invested effort.
For my WyzeCams, I do not have much of an option to use something else, so I went and invested in some Samsung Endurance PRO cards. According to some websites, those are rated very high for multiple/repetitive read/write. Though, only time will tell.
Thank you @mstormi for standing by your position, and convincing many of us that this is such an important aspect.
Any given hardware can fail. Sd cards, ssds, memory etc. I think your sample size of 2 failing sdcard is not big enough to draw any conclusions.
Comparing an openhab system with zram and a camera recording 24/7 (assumption) is not valid. You have far many more writes with the camera.
Using openhab and zram, you will have very few writes.
Thank you for this! I also was not believing that SD cards could run into problems, but had to experience it nevertheless (not on openhab gladly).
Eversince I put openhab on a SSD, which was super easy with the openhabian config tool!
@seaside … and your point is? I was merely reporting on an incident i.e., failure of SD cards. In fact I’ve had 3 failures, the 3rd was a generic MicroCenter card on my DashCam. I never claimed that my ‘experiment’ was valid nor significant/representative, yet I know all about durability testing for electronic/mechanical devices. My post is NOT about that. If however you’re interested in setting up an experiment and count how many read/writes before MBTA, I sure can help set that up for you. Will you provide the test hardware and the samples? Let’s keep this simple and only run 2 brands: generic/cheap cards vs. Samsung Endurance PRO. If we see a difference, we can then extend to other brands.
We have of course to decide on a suitable sample size and run a DOE so we capture all the factors that could induce variability in the results
I think I misunderstood your post. Sorry for that.
I’m saying the sample size is too small to draw any conclusions. I think we all agree that sd card wear out is a problem in general. For openhab using a standard size sd card 32gb+ and zram sd card wear out is not a problem, has anyone.claimed it is?
Sounds like a fun project testing sdcard wear out, i have too many ongoing projects right now so won’t be able to contribute.
My openHABian “test lab” (a single RPi actually) is located 2 stairs down from my PC so for every installation test I had to run the stairs. I ran them countless times until I have burnt those 2 SD cards I mentioned. Ok maybe one day it turns out I was lucky because this ensured I get me my sports dose in Corona times, but fun? No that was not fun.
@mstormi … I wonder, do you have a Fitbit that keeps track of the number of stairs climbed while doing this?
Better yet, does OpenHab have bindings for Fitbit (which is now owned by Google) ?
What type of conclusions are YOU looking for? Are you interested in MTBF, B10 life, … For me it’s simple: do they fail or not? In my world (I do Acoustics/Vibration/Durability) we have components that have infinite life (when the max stress is LESS than the endurance limit) and we have components that survive 5-6 years, depending on market/customer expectations.
So, when you say the sample size is too small … too small for what? Too small to draw conclusions? Conclusions for what?
@mstormi and others have told us that, to extend the SD card’s life, use the biggest card you can find. This makes sense, as the larger the card, the fewer read/writes any given area of the card sees, assuming the card’s controller is smart enough to distribute the read/writes ‘evenly’ across the entire memory chips.
I read an article about 20 years ago, when everyone was moving away from print books to digital media (CD/DVD media). In the article, the author challenged the industry to come up with a reliable long-term storage solution for manuscripts. In his view, those new solutions deteriorate over time, far quicker than paper. We have today books that have survived several hundred years. Can you think of a media (diskette/SD/CD/…) that can survive more than 10 years? Incidentally, it was the time when I was finishing up my PhD thesis at MIT, and the school asked that we submitted both print copies as well as PDFs. It is then that the discussion started as to whether such media had a ‘longer’ shelf life than paper.
You might think 10 years is too long, as computers’ power and storage density would increase substantially over those 10 years. Think of this then: While everyone is always looking for the latest software version and the like, Boeing has their own in-house software and CAD development. Why, because their typical aircraft is expected to be in service around 30 years. Can you name a single CAD/software package today that can read/open files that were created 30 years ago? I’m digressing.
Just to add to this (I know most with knowledge will already know/do this)…
I’ve not had a micro sd card fail on me to date (even 10 year old 16mb ones which I use for a quick copy now and again now from old cameras and MP3 players) ‘touching wood as i say this’.
What I do get all the time is the adaptors to make them full size or usb readers fail. The amount of times I’ve been close to throwing an sd card out and tried one last adaptor and bam… there it is.
@mstormi - Good read, thank you. bookmarked for a deeper dive later today.
@delid4ve - Good point Dave. I have multiple adaptors too. In my specific case, is that when I load them in my computer, I do that one at a time, and I use the SAME adapter for all uSD cards. Some of the cards are readable, and some are not … yet in the SAME adapter. Maybe the sample size is not large enough … but to me (in my unique situation) it is the actual card, not the adapter.
You are absolutely correct though, the multiple insert/remove could damage the small metallic parts in the adapter as well. Good point! … do NOT throw away those extra adapters … you never know when you’d need another one!
Too small to draw conclusions on what sd card wear out is in openhab context.
I’ve actually worked as an android developer for a major mobile phone manufacturer, working with smart card applications on sdcards where wear out is a major factor.
What are you saying? You see wear out your cameras recording on sdcards? I’m not surprised, is anyone surprised? I thought we were talking about wearout in the openhab context. Wear out in the openhab context is not a concern if you are not doing anything crazy and stick to a normal size sd with zram.
Otherwise I don’t disagree with you, I think mstormi is mostly right in his recommendations and had done a great job in implementing, supporting and arguing for zram, and sdcard management.
… but to me (in my unique situation) it is the actual card, not the adapter.