[mythtv-commits] Ticket #8962: playbackbox.cpp:extract_job_state() inefficient

[MythTV]

#8962: playbackbox.cpp:extract_job_state() inefficient
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 Reporter:  danielk           |          Owner:  wagnerrp
     Type:  Developer Task    |         Status:  assigned
 Priority:  minor             |      Milestone:  0.28
Component:  MythTV - General  |        Version:  Master Head
 Severity:  medium            |     Resolution:
 Keywords:                    |  Ticket locked:  0
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Comment (by stichnot):

 I agree that in principle it would be nicer to add this directly to
 ProgramInfo and ProgramList and benefit from automatic PBB updates when
 changes are made.

 However, it is complicated by the fact that a given ProgramInfo can have
 multiple job queue records associated with it - commflag, transcode,
 metadata lookup, user jobs - and each can be in a different state, so it's
 hard to pack that all into a single ProgramInfo field.  Unless we're
 committed to only transferring a summary of specific state information
 about commflag and transcode jobs only, and encode that into a single
 field.

 In the meantime, I've attached a simple patch that locally caches the
 entire job queue and reloads it at most once every 5 seconds.  This
 greatly improves the sluggishness of navigating the Watch Recordings
 screen.

 By the way, at least with my theme, every cursor move in the Watch
 Recordings screen fires off 4 jobqueue queries for each item displayed
 (plus a few extra queries).  With this patch, changing the selection
 creates 3 queries total - 2 for card inputname and one for bookmark
 position (for preview generation) - plus 1 jobqueue query if it's been 5
 seconds since the last query.  Not perfect, but an order of magnitude
 better than before.

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Ticket URL: <https://code.mythtv.org/trac/ticket/8962#comment:8>
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