Adding storage to 4th Gen Tablo

How does adding storage to the 4th Gen Tablo work?

If I add a USB 3 64GB Flash Drive to the USB port on the Tablo, and format it on the Tablo, will that add to the 128GB of Flash that is built into the Tablo, or will the Tablo substitute the 64GB Flash Drive in place of the built-in 128GB?

When I do it, I cant see the 128GB built-in Flash any more in the settings…

Using Flash drives is not recommended.

I believe all NEW recordings will use the external drive. Not sure what happens to recordings on the internal drive. I assume they remain there until deleted.

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Ok. Interesting to know that Flash drives are not recommended. Why?

I thought that as long as they are USB 3, they should have the transfer speed to work just fine. No?

maybe it’s because only SLC Flash memory might work.

Durability. DVR recording has alot of access, especially if recording/playing multiple recordings. Flash drives are mainly for storage or file transfer.

There can be some delays in non-SLC flash

And as I understand it, you cannot use BOTH internal and external storage. If you connect external storage, the internal storage is disabled and all recordings go onto the external device. Perhaps the good news is that if there is no external storage, all recordings would be transcoded to compress them, with potential loss of resolution. If external storage is connected, all recording go there and are retained in their native format, preserving as much video resolution as possible.

Flash memories have what we call a wearout mechanism. We write to a cell by depositing a charge that distorts the orbits of the electrons in the dielectric in the cell. We erase the cell by removing the charge. Erasing the cell allows tha electrons to return to their resting state. The problem is that they don’t return all the way to their resting state. There is always what appears to be a small amount of additional charge left behind. The residual charge keeps increasing with each write/erase cycle until reading the cell shows that there is no data there,

Consider bouncing a tennis ball. Drop it from a certain height. When it bounces, it doesn’t return to the height that it was dropped from. The height that it rises to with each successive bounce is reduced until it finally stops bouncing and rolls away.

The ball loses energy with each bounce. In other words it leaves some energy behind with each bounce the same way that some charge is left behind to accumulate in the flash cell when erased.

The SLC flash can handle 50,000 to 100,000 write/erase cycles while the MLC flash will become stuck at 5,000 to 10,000 cycles. SLC is best for the Tablo environment where video is recorded and possibly erased multiple times per day. MLC won’t last long in this environment.

Some additional reading @Gadget_Junkie

I think (maybe) the point was with regards to thumbdrives, SD cards, and such, which come with a wearout mechanism called, “you get what you (don’t) pay for”. They aren’t designed (in general) for heavy use.

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100%

Great for archiving pictures of your cat, but not great for recording/deleting/re-recording/storing/viewing video.

While not USB thumb drives, there are SLC SD cards designed to record continuously(24/7) in security and car dash cams. I’ve got some 128GB SD’s that have been going for over 2 1/2 years.

You just have to do “due diligence” with regards to products that might have higher durability, vs. “deal of the day”.

I must admit that training myself to not use USB flash drives on these devices is taking some time since my other OTA PVRs required them. Hopefully, (if I can ever get these up and running properly) I’ll one day soon head out and buy some proper external storage.

I’d like to say you did an excellent job explaining how storage works. I wish I’d have come across your definition years ago since most of what I’d read then seemed like such gobbledygook! I keep looking at flash drives as throwaway disks I can just replace every so often due to their prices. I definitely have an interest in upgrading my internal to higher capacity storage, but if I can’t get the Tablo to work right, it would just be a waste of money.

Old habits die hard, man.

While this is very informative in how to add external storage, what are the steps to take when you no longer wish to use it?

I would like to stop using my external drive and go back to using the internal flash. I do not want to factory reset the Tablo because I am very sure there are some older recordings still on the internal disk.

Everything I have come across mentions a factory reset or is for older models of Tablo when you want to migrate drives. Neither of these are applicable.