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by gmazza 3560 days ago
Designed-for use-case for an SD card is a buffer where a photo/video camera will save footage sequentially, then you copy everything to your PC/laptop and reformat the card.

When used as a generic storage with a complex write/delete/overwrite pattern, most card would start corrupting data fairly quickly.

2 comments

I understand its use case. Now imagine you're on location shooting, and you're fumbling around with tiny SD cards. It wouldn't be the first time I've dropped one. Even compact flash I try not to put TOO much work on one before I switch them over.

To say that every consumer is going to use it only as a temporary medium, I think is overly optimistic.

I think part of the appeal of high capacity cards is that you spend less time fumbling with cards. A 1TB card would probably last an entire day of shooting HD video. As an amateur photographer, I generally keep 2 extra SD cards on hand but they're backups and not used. I don't think I've ever filled up the 64GB card that I shoot with and at the end of the day I move off what was shot. If I'm shooting on vacation I'll generally leave a copy of the images on the card so that I have 2 copies floating around but I've yet to fill up the card.

This card probably isn't targeting the consumer market. I think smartphone cameras have cannibalized much of the Point-and-Shoot camera and PVR market. That being said, I think most consumers purchase one SD card when they buy their camera and it's the only card that camera ever sees.

I get what you're saying, and it is a concern, but there is a decent argument (to me, anyway) that with 1TB you probably won't be taking the card out to be fumbling with it in the first place. Even with on-location shooting, "I filled up a 1TB card, I need to archive it" is probably a good reason for a lunch break.
No one in their right mind would fill a 1TB card before swapping. That's an insane amount of potential lost. I could see it as a secondary backup disk in DSLR about it.
If you're recording 4K video, a terabyte is about two hours of recording time. Plenty of folks will fill that before swapping.
Nobody in their right mind would have thousands of photos with no backup, but most people never backup anything.
So what's your argument here, that you agree with me?
He is saying that people will fill a 1TB card before swapping exactly the same way that people often leave thousands of photos floating around without backup.
Not that you're wrong, but [citation needed]. Mainly because you use a microSD card to boot the Raspberry Pi. Also, in my Yearbook class in high school, we almost never formatted(?) our cards. Granted, they were only 32 GB or less to avoid SDXC, but still.
This was mostly from a personal experience of running couple of dozens Raspberry Pies. To elaborate:

- Cheap cards would start corrupting right in the middle of first "apt-get update && apt-get upgrade";

- SanDisk Extreme Pro 16GB fared much better, but still we had several failures after half-a-year;

- Failure mode in both cases - corruption in superblocks and inodes, journal doesn't help much when recovering (we use ext4).

As a result, we settled on splitting each card into two root partitions - active and standby. To upgrade, overwrite standby one with dd, switch active/standby by editing /boot/cmdline.txt, and reboot.

I have had half a dozen SD cards fail (corrupted) on my RPi in a 4 month period - but it turned out to be caused by anaemic power supply. I never got a corrupted SD card since I got a 2.5 Amp adaptor - this was 18 months ago with the very same RPi.
Quite often with the RPi, the problem is more failed-to-shutdown than FLASH-failure.

People unplug those things without shutting them down correctly.... quite possibly that was the problem, nothing inherent to FLASH or SD cards.

Why were you avoiding SDXC? Was it a technical deficiency in SDXC or limitation in your hhardware?
We did have a few cameras that supported SDXC, but the majority didnt. It was easier to just use SDHC and not have to worry about what card works in what camera. Besides, 32 GB was plenty because we almost never shot in RAW (high schoolers aren't professionals); I think only me and 3 others knew about working with RAW.

So to answer your question, space wasn't a premium, and because of the technical and human limitations of SDHC vs SDXC. I'm sure some of those cameras had firmware updates that would add SDXC support, but we didn't need it.

I'm not the parent, but SDXC on my Raspberry Pi causes kernel panics after ~6 hours of operation. It's entirely annoying.
Are you formatted as exFAT? Because it's my understanding that Windows will refuse to format an SDXC as anything but.
I believe it was ext3 or ext4, but I'd have to look.