Continued problems with DVR server dropping offline?

Channels DVR Server
#21

With this setup, the power requirements of the T7 (around 1A peak from a quick search) are added to the power requirements of the RPi itself. While that power supply should cover both (on paper at least), you are right at the edge. (Stay away from the WD mechanical drive-- it would consume even more power.)

I/O errors on SSD drives are typically caused by power issues (the SSD controller lost power mid-write). On the RPi4, I think the red power LED will blink (rather than remain constant on) when power is marginal. Am guessing you cannot see the power LED when the Pi is mounted in that case.

After it has been running for a while, enter:

dmesg | grep -i voltage

RPi4/Rasperian logs voltage warnings and the command above will filter them out.

The UPS wont make any difference as that only protects against house power failure. It does not alter what the power supply can deliver to the RPi and how much the RPi can deliver to the USB ports. Is anything else connected to any of the other RPi ports (aside from the keyboard)? The RPi paper limit is 1.2A (6 watts) for all USB devices >combined< (not per port).

If you can confirm its a power problem, then two possible solutions-- power the SSD via its own supply (annoying since that requires an external USB 3 hub which is one more failure point) or potentially a higher capacity power supply. Unfortunately, even a higher capacity power supply wont alter the USB 1.2A / 6W limit. Probably worth some google time to see how others are handling the power needs with external drives on the RPi4.

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#22

I use the power supply from the CannaKit with my PiDVR, and also use some generic one that came with one of my cases on another pi.
All of my pi's are cpu overclocked.
But i did run them for 1 week at stock settings just to make sure they were stable first.
I have had no issues with power.

Even my second PiDVR that is using a usb 3.0 to sata clear case that has a deathbeam leds in it, has no power issues, and that would use more power than the Samsung T7 i use in my DVR.

Not really sure why this user is having issues, maybe a defective pi board?
Maybe cooling? are the heatsinks installed right?

#23

Speedingcheeta and Vraz..

Morning fellas.. Again, thank you both for continuing to put your brains on this project for me.. So yesterday afternoon I thought "well, I don't have another pi handy, but I can switch out the drives and see what happens.. after all, it can't work worse than it is now!".. So I reformatted the 4 TB Western digital drive (The one recommended in the Channels set up article), plugged it in and let everything settle in. I then recorded multiple programs while having the pi hooked up to a monitor. Previously, I was getting an almost constant stream of text on the screen (as I photographed above).. As of this morning, I only have the initial 20-30 lines that appear during startup. I'm currently recording 3 different shows, and will swap out to different channels immediately after for multiple hours to do a "worst case" test.. But so far, I really think that there is something wrong with my Samsung T7.

I think that the pi heat sink is set up correctly.. I used the little thermal pad on the processor, then inserted it into the case.. I"m seeing temps of 40 deg C when Idle, and close to 50 when I push it recording multiple programs?

I did reformat it several times when it wouldn't boot, perhaps during the formatting/loading server image something got corrupt and isn't fully reformatting now? I"m not sure how much of a 'full erase' the dvr server imaging process does?

If the WD drive passes the torture test this morning, I'll return the Samsung drive.. My next question is this: Am I even going to realize the full 1000mbs of that drive with a Rpi? I think that speed requires USB 3.2? Pretty sure the Pi doesn't even have the capacity.. Stated another way, dollar for dollar, would I be as well off with a Samsung Evo internal drive, paired with a housing? I'd like to have more than 1TB but really don't want to spend over 300 dollars on a 2TB T7..

Thanks again for your thoughts.. progress is happening!

#24

An ssd is still faster than any platter drive.
I didn't notice that this new usb 3.1 or even 3.2 was a thing....don't care.
I just got the T7 cause i could not find the T3 anywhere, and that is the model of small ssd i have used and still use for many years that has seen extreme use for many things, most often file backups and syncs, Acronics HDD images, very heavy read and writes over the years, and it is still going strong. So i trust its design.

I use a 500GB T7 on my Channels DVR. Which is more than enough for me. I do not record much, and never have more than 5 or 6 programs left on there to watch, then delete. I have a 1TB Samsung 2.5in SSD in a cheap enclosure attached to my other pi DVR that my mother uses, she does doe much more recording than me, but tends to copy off the files to her other portable drive and keep them, then delete off the dvr.

If you are one that wants large storage and keeps many local recordings or collections, then yes, large TB ssds are much more expensive than a HDD. For that use case, then it is fully understandable to use a large TB HDD over a smaller SSD.

Formatting a drive should not hurt it....but I never did that. I just pulled the T7 out if the box, connected it, and used the Pi Image software to flash the Channels server image, and it just worked. The other ssd for the other pi, was used before, and wiped, no partions or filesystem, and it imaged fine.

Not really sure about all the troubles you have had.
What works fine for one person, does not mean it works for the other.
But I guess it seems to be a trend, users of these SBC (single board computers) like the Pi, either you have zero issues and it just works, or, you run into issues or quirks you have to troubleshoot.

#25

Glad you are making progress. Did some digging and it appears the WD Elements w/mechanical drive uses less power than the T7-- a surprise to me. Looking closer, the T7 is a performance oriented product w/USB 3.2. The WD is a value oriented product w/USB 3.0. I will maintain my guess that the T7 is pulling too many watts and you are running into brownout conditions that ultimately causes data corruption and OS errors.

Don't understand your reference to "realizing the full 1000mps of that drive". USB 3.0 (max supported by the RPi) is around 4.8Gbps bandwidth and modern SATA (the interface used by the internal HDD is 6.0gbps)-- pretty close. Video recording and playback uses nice sequential access patterns that play nicely with mechanical drives. If you go the SSD route, you will be entirely bounded by the USB 3.0 interface speeds (at their core, all SSDs are way faster-- that is why non-embedded applications use NVMe for SSD).

Am sure an EVO would saturate the Pi USB interface without issues (which I think is the gist of your question). You get back to the question of power budget. Samsung does provide information for bare drives and I copied the 870 EVO information below. Not sure what "burst mode" means, but 5W is on par with the T7. You could get a USB to SATA adapter that supports its own power supply depending on whether you think the T7 was just defective vs power challenged. A fun project and sure you will enjoy once its all done. Best of luck.

Idle mode power usage:
250GB: Max. 30 mW
500GB: Max. 30 mW
1TB: Max. 30 mW
2TB: Max. 35 mW
4TB: Max. 35 mW

Active mode power usage:
250GB: Average: 2.2 W Maximum: 3.5 W (Burst mode)
500GB: Average: 2.2 W Maximum: 3.5 W (Burst mode)
1,000GB: Average: 2.5 W Maximum: 4.0 W (Burst mode)
2,000GB: Average: 2.5 W Maximum: 4.5 W (Burst mode)
4,000GB: Average: 2.5 W Maximum: 5.0 W (Burst mode)

#26

Wow.. thank you so much for posting those numbers! I'm going to order a 1TB evo 870 and a USB 3.0 enclosure and see how that flies.. So far so good today though on pushing the Rpi as hard as I can.. I did get temps up to 52 deg but no I/O read/write errors!

Will report back!

#27

Yeah that is probably a good move. I have an Intel NUC and a 10TB drive in a powered enclosure and it works quite well. No power issues at all. I have a 2TB SSD as my main DVR drive and then I have a script that runs every night at 3am that copies every video file that is over 30 days old to the 10TB drive. Kind of gives you the best of both worlds, speed and storage.

#28

I would say that max power draw u mention would be for 3.2 port. A 3.0 port won't put out more than the 3.0 standard. The ssd controller would revert to 3.0 mode.
Regardless, i don't think its a power issue when using the t7.
Too many other janky issues it seems.

#29

Although Samsung specs show 1.5A (7.5W) max, I think that's because it's the max for USB 3.2 Gen 2.

I remember reading a benchmark/review that showed the Samsung T7 peaking at 4.05 Watts
Found it https://www.anandtech.com/show/14661/usb32-g2-portable-ssds-roundup/6

#30

Hey all..

New EVO drive showed up last night but probably won't have the enclosure until tomorrow.. As of this morning though, we are 24 hours in and no errors being posted when I connect the pi to the monitor.. Not sure what to think about all of the power issues.. From reading above it looks like the 1TB evo won't hit the 4.5 watt limit for USB3 on the wiki page.. I think there was something wrong with the T7 drive that I tried.. I was tempted to try another one but afraid I'd have the same issue. Anyway, will report back with how the system behaves with the EVO in an enclosure!

#31

Update:

Installed EVO drive in an enclosure 2 days ago.. I've done back to back, triple recordings at a time now with commercial detection even pushed up to 3.. Zero errors, no dropping.. So it appears that all of these problems were coming from using that T7 drive for some reason, be it a power issue, or just a faulty drive..

Thanks so much to everyone for your assistance, advice, and suggestions! I think we have this one sorted!

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