February 27, 2011

TiVo question

Does anyone know why the TiVo's 1Tb disc is only capable of recording 100 hours of HD*, whereas the V+ 160Gb drive records 20 hours? By my calculation the Tivo disc should take 125 hours (8Gb per hour).
* According to the manual: "Your TiVo box comes with a whole terabyte of hard disk space. That’s about 400 hours of standard TV, recording or 100 hours of HD TV"

5 comments:

Coops said...

the reason behind this is that when a drive is formatted you lose approx 7% making the drive approx 930mb. They may also partion the drive for software etc, this then reduces it further.

Hope this helps

Neil Gillibrand said...

The current v+ has a partition for pausing lice tv. Perhaps this is the same with the tivo box thus reducing the amount of disk space available for recording?

question42 said...

With 3 tuners, each with their own buffer (30 minutes ISTR), I can imagine that they'd have to put aside enough for that, in HD, too.

Nialli said...

Scottivo's suggestion is that there may be an area of the TiVo's disc reserved for "recommendations", much like Sky Anytime grabs part of the Sky+ box's disc.

JRW said...

Sad geeky post:-
Four things eat into the 'terabyte'.
(1) A 1TB drive is never 1000GB. I just checked one model and it was 986GB.
(2) Software doesn't do Gigabytes etc., which are Base10. It thinks binary, Base2, Gibibytes. 986GB=~920GiB. (Its says GB, its lying. Difference at GB level is ~7%.)
(3) 'Formatting'. All file systems have an overhead. If we assume its 3% we are down to 893GiB. That's >10% of what ypu'd assume you got with a TB drive and no user data is on the drive yet.
(4) 'Scratch/work space, wiggle room'. No disk can be 100% used, but with three tuners needing their own 30 minute buffer an extra 1.5 hours of space is taken on top of wiggle room. The more clever things you try do do (EPG, viewing history etc.) the more sctratch/work space is needed.