[mythtv] [mythtv-commits] Ticket #3350: Threaded Preview Gen does not use qmap index consistently

[Mark Spieth]

> #3350: Threaded Preview Gen does not use qmap index consistently

I think there might also be another problem. I suspect in threaded preview 
gen mode, if you scan each item in playbackbox quickly and all have no 
preview image, then they all get launched simultaneously.
this can cause excessive resource usage, esp on a remote FE with network 
usage. if 10 are generating images, then you get 10x network usage during 
avf initial stage where it works out what the recording is.

Is it a good idea to only ave one preview gen going at any one time per FE 
or perhaps shift preview gen to the/a backend as a job like commercial det 
etc.?

mark