[mythtv-users] Filesystem of choice for recording drive?

[Simon Hobson]

Warpme <warpme at o2.pl> wrote:

> A: traditional drive (i.e. WD Green)
> 1.app reads sector
> 2.CRC errors discovered
> 3.HDD controller rereads bad sector multiple times with hope that drive CRC algorithm redundancy data will recover error.
> 
> B:AV streaming optimized drive (i.e. WD Purple)
> 1.app reads sector
> 2.CRC arrors discovered
> 3.HDD rereads sector only few times with hope that drive CRC redundancy data will recover error. When fails - read operation ends with success but HDD returns bad data!!!
> 
> Now:
> A.3 can be 10..60sec or even more.
> B.3: can be let say 0.5sec (time in which HDD cache can buffer incomming write data when write to platters is blocked by read recovery)
> 
> As 3 is write blocking, we can say:
> WD Green will damage recording for hope of getting glitch-free playback
> WD Purple will try keep recording with price of glitches in playback
> 
> What is better for myth recording drive?

The latter is fine *IFF* the corruption isn't in the filesystem data. So while you might not care too much about a glitch in the recording, you probably do care a lot about glitches in the filesystem data that will corrupt the filesystem.
Or, getting a read or write error and having the filesystem unmounted dirty (or whatever the OS does in that case).

I wouldn't assume that such a behaviour isn't without it's own issues.