[mythtv-users] Building a new MythTV Backend for 2022

[Mike Perkins]

On 11/01/2022 01:57, James Linder wrote:
> 
> 
>> On 10 Jan 2022, at 6:06 pm, Mike Perkins <mikep at randomtraveller.org.uk> wrote:
>>
>>> If you want to record to the SSD, then you are likely to hit the
>>> lifetime write limit fairly rapidly.  But just running MythTV and
>>> normal Linux on an SSD and there are no problems with lifetime.  You
>>> still need to worry about it just dying unexpectedly, like any disk
>>> drive (or any electronics, for that matter).
>> I would think that is the other way around. Sure you are writing TB chunks to a recording disk but it is written once and then read for a while until deleted. On the other hand that database is getting *hammered* all the time as it updates e.g. seek tables. And do not forget the daily mythfilldatabase updates! Lots and lots of small updates to files and inodes all over the place.
>>
>> The one thing that you can be certain of with any (currently manufactured) SSD is that it is guaranteed to fail. Once it reaches the lifetime limit then bang! it's gone. On the other hand, a looked after HDD will just keep spinning.
>>
>> Processor speed and memory increases are such that I don't need that extra disk write speed, not for something as non-critical as mythtv. SSDs undoubtedly have a place for certain use cases but thrashing a media database isn't it, in my view.
> 
> Mike having been there, which is why I’ve been so opinionated, once you reach lifetime limit little happens except the disk is read-only. Mo bang, no gone, nothing other than read-only.
> 
And of course my personal experience is the opposite. In a drawer I have 4 SSDs which just quit 
dead, not at the same time or in the same box. Couldn't get anything off them at all.

In fact, if SSDs were to customarily fail to read-only that would be a much better outcome than I 
could get from any HDD, but nobody is ever going to promise that.

At the moment SSDs are still /relatively/ new technology compared to HDDs, which have been around 
since computers moved to transistors. I have a suspicion that makers love SSDs because they are easy 
to manufacture and, since they have a guaranteed lifetime, also a guaranteed replacement cycle.

I use SSDs for laptops, thin clients and test equipment where the data volumes are small enough that 
I don't care about lifetime length. I will not use them in servers, though, except perhaps as boot 
media before running off LVM volumes.

As always, YMMV.

-- 

Mike Perkins