[mythtvnz] New list member - Hardware recommendations

[Wade Maxfield]

On 12/01/2012, at 8:12 PM, criggie wrote:

> Why?  The mysql output is a single record to the recordings table, a 
> single record in the recorded table, and maybe a few state updates that 
> the tuner is in use.

Plus the 7200 entries in the recordedseek table per hour of each recording.  Multiply that by the number of simultaneous recordings you can do, plus the number of user jobs, plus number of playback streams and it can get to be a meaningful number.  Add in the scheduler as well.  That seems to be the biggest bottleneck in bigger systems.  People have had spluttering recordings when the scheduler kicks in, mainly on systems with large numbers of schedule rules, high number of channels, and high number of tuner inputs and where they share the same drive for recordings and mysql.

Personally I have 2 recordings drive (2 x 1TB) and a separate OS drive.  With 2 DVB-S cards set to 3 virtual tuners each, plus the PVR150 for Sky that's 7 simultaneous recordings (which does happen quite regularly with post-roll overlap settings), 3 commflag jobs, plus up to 4 playback streams (only 4 people in the house at the moment) and at peak times there can be quite a high level of disk activity, not just in MB/s but in I/Os.

I'm not saying everyone *HAS* to have a separate drive, but it can be useful as your system grows.

 - Wade