Q about SSDs for computer hardware experts

cliveb

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Looking for opinions about using SSDs in write-intensive applications.

I'm about to build a new DVR. This will be used as a traditional time-shifter: record OTA broadcasts, watch some time later, then delete.
So the storage is going to be doing lots of write operations.

I had always got the impression that this is not a good use of SSDs and so would be inclined to use a HDD.
But I have to admit I'm not up to date with how modern SSDs work, so maybe it's no longer an issue.
The reason I'm interested in an SSD is for the silent operation and low power consumption.

Any of the hardware experts here got a view?
(I did try asking about this on the MythTV forum, but the only answer I got was someone just saying they use HDDs, without any explanation why).
 

GreiginFife

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Looking for opinions about using SSDs in write-intensive applications.

I'm about to build a new DVR. This will be used as a traditional time-shifter: record OTA broadcasts, watch some time later, then delete.
So the storage is going to be doing lots of write operations.

I had always got the impression that this is not a good use of SSDs and so would be inclined to use a HDD.
But I have to admit I'm not up to date with how modern SSDs work, so maybe it's no longer an issue.
The reason I'm interested in an SSD is for the silent operation and low power consumption.

Any of the hardware experts here got a view?
(I did try asking about this on the MythTV forum, but the only answer I got was someone just saying they use HDDs, without any explanation why).

The issue has been, and still is, re-write cycle capacity of SSDs. Even the best out there are still only offering around 250,000 rewrite cycles (up from the "old" 100k cycles). Whilst that sounds like a lot, your DVR is going to be constantly writing and re-writing data, buffering etc.

There is the option of enterprise grade SSDs which have much increased overwrite cycles and are used in big data centres. These still don't match up to the likes of Western Digital Purple HDDs (designed for DVR/CCTV use with 1M+ rewrite cycles) but do offer much increased lifespans (varies wildly from manufacturer to manufacturer, as do commercial grade SSDs).

The drawback is that a 960GB eSSD is around 6 times the price of a commercial one, even as far as 20 times the price.

For the marginal gains in performance it just isn't worth it IMO. You'd see an improvement in FFW/REW and save applications and yes it'd be quieter but you'd probably replace the drive 4-5 times over the life of a HDD.

With a HDD, you can get little rubber grommets that sit under it to dampen vibration, I have these in my CCTV DVR and it's so quiet sometimes I need to check if it's still on.

Power consumption over the life of the drive is really going to be marginal IMO.
 

cliveb

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Thanks very much for the advice. You've confirmed my belief that SSDs are not suitable for write intensive applications. I'll stick with HDDs.
 

cliveb

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Power consumption over the life of the drive is really going to be marginal IMO.
PS to my previous reply:
One of the reasons I was interested in the lower power consumption is because I'll be using a RPi4 for the DVR, and an external SSD can be powered direct from one of its USB ports.
A HDD draws too much current from the Pi and therefore needs a powered USB hub. But that's no great hardship.
 
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