[PVR] Fix for slow metadata updates of recordings

[popcornmix]

See: http://forum.kodi.tv/showthread.php?tid=210774

metaron identified that entering the recordings screen wih 850 recordings on a Pi
was taking about 40 seconds. The database is opened and closed for every recording,
and this dominates the time taken. With the database open/close pulled out of the loop
it now takes 1.4 seconds.

[popcornmix]

jenkins build this please

[FernetMenta]

great! there is an issue with vdr 2.0.3 which triggers recordings update frequently.

[popcornmix]

ping @opdenkamp

[opdenkamp]

nice find. i think we can keep an open db instance in CPVRRecordings, so we don't need to open and close it in CPVRRecordings::GetSubDirectories?

[popcornmix]

@opdenkamp Open database in constructor and close in destructor, and just rely on it being open within this class?

[opdenkamp]

yeah afaict that should be okay too

[popcornmix]

@opdenkamp updated to only open/close the database once with the CPVRRecordings class.

Note: I don't have a setup to test this (it does compile).
It will be out in a newclock4 test build tonight, but if anyone who uses PVR/recordings can test this doesn't break anything, that would be helpful.

[janbar]

@popcornmix I will test it asap tomorrow.

[popcornmix]

@Jalle19 updated with your suggestions

[Jalle19]

Thanks, looks good. @xhaggi any thoughts? The change should be pretty harmless so I don't think a merge is that far away.

[opdenkamp]

jenkins build this please
feel free to merge once @janbar has tested it

[janbar]

Tested (including Jalle19 fix) and approved !

[xhaggi]

Does it make sense to move UpdateMetadata() to CPVRRecordnings and pass the recording as parameter instead of the database reference?

[opdenkamp]

could do, but let's do that separately and get this issue fixed first.

[xhaggi]

it will fix the issue too and we don't introduce code that we will change later. if fine for @popcornmix

[opdenkamp]

i don't see the benefit tbh

[Jalle19]

Goddammit, I forgot it was unsquashed.