General issues regarding F2FS rootfs partition


Grench

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@God Ginrai - We got the microSDXC slot built in. Having to hold a shoulder button on a handheld console to 'activate it' for booting is a very tiny price to pay to have it exist. So, ahem, quitcherbitchin.

1. If you're at the least bit concerned about retaining a set of files, make a 2nd copy to a 2nd drive/disk/media in the same device or use RAID 10.
2. If you're more than a bit concerned about retaining a set of files, make a 3rd copy on a piece of media held in a fireproof safe or safety deposit box completely separate from any device.
3. If you're really concerned about retaining a set of files, make 3 offline copies, rotate through them to create your backup set and store them in three separate offline storage locations.

Cloud storage is fine for -sharing- files. I wouldn't trust any cloud service to keep files -safe- though. Anyone who only keeps only one copy of important files AND stores them on a mobile device is simply asking for heartache.
 

wdt

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Samsung and sandisk have been faked. I think tosiba has some arrangement, they did partner in making flash
How long a nand will live depends a whole lot on how many bits/cell,, ie,
SLC, MLC, TLC, QLC..... SLC, barring mischance will live for a very long time, long past the device becoming a curio
MLC has a reasonable life, the others rather less. Often, on a better SD the first few megs are SLC, for fat and / directory
Actually, a lot of the quality of the device is in the controller, not only do you have no idea what it is doing,
but it is very hard to find ANY information, they seem to be "trust me".
Well, most people are ignorant enough that may valid, with the remapping and garbage collection
you have absolutely no idea what is happening on the nand
 
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spud42

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Oh? I thought they were really thin - is the space inside that constrained?! :confused:
Nah I’ll just use a USB SSD like the Corsair Flash Voyager GTX.
youre typical NVMe SSD M.2 format will be 22mm by 80 mm up to 110 mm long and will be 3.8mm thick , as has been said i dont think the PCIe lines are exposed for use plus there is not that much room inside the Pyra.

i have a generic 128 MB SD card i have been using for firmware updates for the last 12 years and it was a hand me down from the previous tech. i honestly couldnt tell you how many times it has been formatted and had files written and deleted from it in all those years. it still works but is too small for the newest firmwares i have to update. i was doing it in 2 passes. we have machines that are 10 years old and all the data and user data is on flash/NVRam type devices.. not ever had to replace one.
 

wdt

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MLC came out about 5-6 years ago. Anything older is SLC, may last until lost or discarded
 

Grench

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It amazes me a bit how many obviously fake microSD and SD cards there are on Amazon - many with Prime free shipping where Amazon is shipping them from their own warehouse. Yes - they are someone else's stock not SOLD by Amazon, but shipped by Amazon. Of all the flaky crap that gets sold, this seems to me to be the easiest one to, 'clean up', but they persist. They leave it up to the consumer to be able to distinguish between the two - and tend to make it less than obvious. Annoying.

So, there is a lot of 'buyer beware' still regarding media cards.
 

Phlyra

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It amazes me a bit how many obviously fake microSD and SD cards there are on Amazon - many with Prime free shipping where Amazon is shipping them from their own warehouse. Yes - they are someone else's stock not SOLD by Amazon, but shipped by Amazon. Of all the flaky crap that gets sold, this seems to me to be the easiest one to, 'clean up', but they persist. They leave it up to the consumer to be able to distinguish between the two - and tend to make it less than obvious. Annoying.

So, there is a lot of 'buyer beware' still regarding media cards.
Which ones are “obviously fake”, which “less than obvious” and which ones actually genuine?
 

levi

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Well, as Grench said, it's up to the buyer to distinguish between them. There are programs to help, largely ones that detect cards that pretend to be bigger than they are, so if you fill them with enough data they overwrite earlier pages. But if it's got a duff controller that doesn't remap broken bits then it'll have dramatically shorter lifespan, and I don't know of a way to detect that other than using it for a few months.
 

Grench

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Which ones are “obviously fake”, which “less than obvious” and which ones actually genuine?
I'm not going to provide links to fake cards. Just search Amazon for 1TB microSDXC. Any of the results that are not Sandisk cards and/or are being sold for under $150 are obvious fakes.

Likely genuine are the cards sold by Amazon. Example of a likely genuine (no guarantee on this) card:
Code:
https://www.amazon.com/SanDisk-Extreme-microSDXC-Memory-Adapter/dp/B07P9W5HJV
To check if an item is sold by Amazon and not just them shipping someone else's stock, you need to click on the link under the item description that will be something like:
"New (5) from $259.99 + FREE Shipping"
That should pull up a menu of the sellers of the item -and- show you which of the nested listings is actually sold by Amazon.

Amazon used to include the seller's identification in the product listing but has since moved it to this secondary page - a bit off obfuscation. That is one small additional issue combined with their seemingly purposely broken search has me rather annoyed with their behavior. Still, Amazon, when they are selling the item themselves, have been a solid source for media cards for me. I have a 1TB SanDisk microSDXC for another project and it seems to be genuine. I put 800GB of data on it and binary cross compared it back to source.

If you don't need the capacity or you're not wanting to splurge for the 1TB cards, there are bargains to be found on the SanDisk 200GB and 400GB cards sometimes. I have a half dozen of each (again - other projects) and have found them to be pretty solid cards.
 

Phlyra

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I'm not going to provide links to fake cards. Just search Amazon for 1TB microSDXC. Any of the results that are not Sandisk cards and/or are being sold for under $150 are obvious fakes.

Likely genuine are the cards sold by Amazon. Example of a likely genuine (no guarantee on this) card:
Code:
https://www.amazon.com/SanDisk-Extreme-microSDXC-Memory-Adapter/dp/B07P9W5HJV
To check if an item is sold by Amazon and not just them shipping someone else's stock, you need to click on the link under the item description that will be something like:
"New (5) from $259.99 + FREE Shipping"
That should pull up a menu of the sellers of the item -and- show you which of the nested listings is actually sold by Amazon.

Amazon used to include the seller's identification in the product listing but has since moved it to this secondary page - a bit off obfuscation. That is one small additional issue combined with their seemingly purposely broken search has me rather annoyed with their behavior. Still, Amazon, when they are selling the item themselves, have been a solid source for media cards for me. I have a 1TB SanDisk microSDXC for another project and it seems to be genuine. I put 800GB of data on it and binary cross compared it back to source.

If you don't need the capacity or you're not wanting to splurge for the 1TB cards, there are bargains to be found on the SanDisk 200GB and 400GB cards sometimes. I have a half dozen of each (again - other projects) and have found them to be pretty solid cards.
Cheers for the clarification, very helpful!
 

wdt

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Anytime you get a "new" card in your hand, the 1st thing you should do,
WITHOUT FAIL, is test to see if fake
f3, I use f3probe,, sudo f3probe /dev/sdX ,, be sure to get X right
then, to see how fast,, (within mounted card)
iozone -e -I -a -s 100M -r 4k -r 16k -r 512k -r 1024k -r 16384k -i 0 -i 1 -i 2
for winblows, there is htestw (for size, fake)
 

levi

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Yes, that's the tool I was thinking of. It proved a key shaped 8GB card I bought was really 8GB, but it couldn't protect against the card dumping it's first page of data after a few weeks of being carried about in my wallet.

Amazon used to include the seller's identification in the product listing but has since moved it to this secondary page - a bit off obfuscation. That is one small additional issue combined with their seemingly purposely broken search has me rather annoyed with their behavior. Still, Amazon, when they are selling the item themselves, have been a solid source for media cards for me.
I used to be able to select 'Free UK delivery via Amazon' on the amazon-dot-uk. Since then they've introduced 'sponsored' items that I couldn't figure out, which now seems to have been supplanted by 'from our brands' products, but they smell wrong to me still so I still skip those. And now it shows things fulfulled by amazon which are some of the dodgy sellers you talk about which you can distinguish, but if you click thorough then click through to sellers, quite often there's product which amazon themselves are selling is there for a few fivers more, but yeah you have to click twice after the search ending up with three different pages to find that out these days.
 
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