4th gen internal flash failure

What type of internal flash storage do the 4th gen devices use? I wonder how much recording expressed in hours of HD content these devices are designed to withstand before sectors start to fail.

According to this support article about external storage, content is transcoded from source to save space. So storage should degrade even more quickly.

I’d prefer not to use an external drive due to increased power usage.

Maybe. But my eye aren’t not like I was 20.

Thanks. I’m not an engineer though and wasn’t able to find an answer using my untrained eye.

I did search for terms such as “write”, “cycle”, “max”, “cell”, “TLC”, “MLC”, etc.

Hi Jack,

This article may help: https://support.tablotv.com/hc/en-us/articles/201445336-How-Much-Space-Does-Tablo-Require-to-Record-a-Program .

I appreciate the info. But it doesn’t address my question.

Onboard storage utilizing some form of NAND flash wears out over time with increased recording. The archiving process when not utilizing external storage which transcodes the original OTA source video to a more compressed format will add additional wear to the onboard storage with each and every recording.

My question is what type of NAND flash onboard storage is included with 4th gen devices. As not all NAND flash types are designed equally, how resilient is the onboard storage to this wear and tear? In simplest terms, how many hours of recordings can users expect before this inherent wear and tear begins causing problems?

A typical NAND drive has a failure rate that tends to occur after around 10 years of use. However, because most applications require much less frequent use, the drive’s lifespan is likely to exceed that of the other electronic components in the device.

NAND drives utilize Error-Correcting Code (ECC) to detect and correct data errors, along with other techniques that help extend their operational life (Wear Leveling).

The lifespan of a NAND drive is affected by the number of program/erase (P/E) cycles and the operating temperature. Higher temperatures, especially those exceeding 60°C (140°F), can substantially shorten the drive’s data retention lifetime.

See: Endurance and Retention of NAND Flash

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Don’t you think it’d still be good to get an answer to this from Tablo?

Given a dual 4th gen with only 128 GB of internal storage which can easily be filled up daily by recording morning, news, talk shows, etc. then throw in the transcoding of every recording with a fanless device. I think there’s still cause for concern.

Mean time before failure is usually quoted as the average number of reads/writes. This would typically be 10,000 or more. Since bad blocks are taken out of service I’m more interested in what the minimum downgraded size that is supported. And also what happens if the NAND controller fails.

I’m just curious, why are you concerned about the power usage of an external drive? Modern drives are very power-efficient.

I’m not trying to be argumentative, I really am just curious. Your question about the internal memory is valid and interesting. I just found that it filled up more quickly than I expected so I went with a 2TB external SSD.

Hot climate, 20 year old air conditioning unit. We live in the desert southwest. It has been an especially brutal summer with temperature record after temperature record broken. This is after several years of record breaking summers.

It’s definitely a fair question.

A few watts for an idling HDD certainly isn’t much power consumption. But it more than doubles the power consumption to operate the device measured by a Kil-a-watt at about 4W. I assume that the external drive would be spun down a large amount of time. But I’m just super conscious about minimizing household power consumption since even small amounts add up and add to the heat load needing to be removed by the AC. Electricity bills in the area are commonly well upwards of $200. Many folks report >$300 if they really like to keep their homes cool.

I’ll likely add an external drive in the end. But I was hoping to avoid doing so.

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Could you please explain “minimum downgraded size”?

I would bet it detects NAND memory cells that go bad and doesn’t map data on those cells.

The eMMC can be operated in 1, 4, or 8-bit mode. NAND flash memory is managed by a controller inside, which manages ECC,
wear leveling and bad block management. The eMMC provides easy integration with the host process that all flash management
hassles are invisible to the host

Is the minimum downgraded size the minimum number of good blocks necessary for the eMMC to function?

It’s probably safe to assume that if the NAND controller fails, you’re replacing the entire unit right?

If the controller continues to mark blocks as unusable and you start with 1,000 blocks and 250 blocks go bad I don’t think you have 128GB of flash.

I’m guessing that is why the formatted size is smaller. The formatted size is ~116G out of 128G. The Tablo doesn’t have any user serviceable parts, so if it did fail, you would just need to buy a new unit. For the price point, it will fail eventually.

Nobody knows how long, since that is based on environmental factors. For example, if you lived in a very humid climate, you have shorter lifetime for electronic gear because of the humidity.

Fat file systems reserve a minimum number of inode blocks when formatted. Of course one might ask why I get 115GB and you get 116GB. I want the extra 1GB that you seem to have.

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