[olug] mythbackend.log filling with errors... :(

[Ben Watson]

Personally I don't see how failing channel scans would cause excess
HDD activity; more like excess CPU.  Question: did you notice this
period of increased HDD activity immediately following a recording
job?  Your HDD may get hit slightly during the recording process,
especially if recording HD TV signals.  Though my current master
backend doesn't seem to get too horribly taxed while recording 4 SD
channels simultaneously.

However, at sometime post-recording, MythTV performs additional jobs
on the recording itself.  Notably, scanning for commercials to flag
them for auto-skipping.  Additionally, there may be some transcoding
going on depending on how you've got yours setup.  This process is a
little more intense on the HDD as the backend process has to scan a
multi-GB file.  Half hour SD segments are about 1.1GB and a full hour
is about 2.2GB.  Double that for HD TV signals.  If you were playing
back a recording on this system while this process is going on, then I
could definitely see the HDD getting pegged a bit.

Ben

On Mon, Feb 6, 2012 at 9:28 PM, Dan Linder <dan at linder.org> wrote:
> I'm slowly getting my Mythbuntu system up and running.  I bough a
> cheap ($12.00) indoor antenna at Menards to see what I can get, and
> the HD stations looked pretty good - and that is with my antenna
> mounted on the ceiling in the basement.  But, one thing is causing me
> some concern...
>
> While watching TV last night, my family noticed that the HDD was being
> hit fairly consistently for ~15-20 minutes at a time.  Tonight I
> tracked it down to entries being added to the mythbackend.log file of
> this sort:
> === begin ===
> 2012-02-06 21:01:07.884 Could not find channel 7_1 in TVCT
> 2012-02-06 21:01:07.966
> VCT Terra: channels(2) tsid(0x7ab) seclength(111)
> Channel #0 name(KMTV-TV) 3-1 mod(ATSC 8-VSB) cTSID(0x7ab)
>  pnum(3) ETM_loc(1) access_ctrl(0) hidden(0) hide_guide(1)
> service_type(ATSC TV) source_id(1)
>  descriptors length(17) count(1)
>  Service Location Descriptor (0xa1) length(15)
>
> Channel #1 name(LWN) 3-2 mod(ATSC 8-VSB) cTSID(0x7ab)
>  pnum(4) ETM_loc(1) access_ctrl(0) hidden(0) hide_guide(1)
> service_type(ATSC TV) source_id(2)
>  descriptors length(17) count(1)
>  Service Location Descriptor (0xa1) length(15)
>
>
> 2012-02-06 21:01:07.901 Could not find channel 26_1 in TVCT
> 2012-02-06 21:01:08.050
> VCT Terra: channels(2) tsid(0x7af) seclength(111)
> Channel #0 name(KETV-DT) 7-1 mod(ATSC 8-VSB) cTSID(0x7af)
>  pnum(3) ETM_loc(0) access_ctrl(0) hidden(0) hide_guide(1)
> service_type(ATSC TV) source_id(1)
>  descriptors length(17) count(1)
>  Service Location Descriptor (0xa1) length(15)
>
> Channel #1 name(KETV-ME) 7-2 mod(ATSC 8-VSB) cTSID(0x7af)
>  pnum(4) ETM_loc(0) access_ctrl(0) hidden(0) hide_guide(1)
> service_type(ATSC TV) source_id(2)
>  descriptors length(17) count(1)
>  Service Location Descriptor (0xa1) length(15)
>
>
> 2012-02-06 21:01:08.244 Could not find channel 7_1 in TVCT
> 2012-02-06 21:01:08.260 Could not find channel 26_1 in TVCT
> 2012-02-06 21:01:08.326
> VCT Terra: channels(2) tsid(0x7af) seclength(111)
> Channel #0 name(KETV-DT) 7-1 mod(ATSC 8-VSB) cTSID(0x7af)
>  pnum(3) ETM_loc(0) access_ctrl(0) hidden(0) hide_guide(1)
> service_type(ATSC TV) source_id(1)
>  descriptors length(17) count(1)
>  Service Location Descriptor (0xa1) length(15)
>
> Channel #1 name(KETV-ME) 7-2 mod(ATSC 8-VSB) cTSID(0x7af)
>  pnum(4) ETM_loc(0) access_ctrl(0) hidden(0) hide_guide(1)
> service_type(ATSC TV) source_id(2)
>  descriptors length(17) count(1)
>  Service Location Descriptor (0xa1) length(15)
> === end ===
>
> I did a Google search of the "Could not find channel" and "in TVCT"
> and I found a number of hits.  Unfortunately they are all people
> asking the same sort of question.
>
> One thread suggested re-scanning as the solution... I have just done
> that so now it's a waiting game.
>
> Questions:
> 1: What is the error message trying to tell me?  I haven't grep'ed the
> source to look for the source, but the output is lacking in a reason
> for it being generated.
>
> 2: Any other MythTV users seeing the same problem?
>
> Thanks,
> Dan
>
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