[mythtv-users] scan for changes

[Mark Lord]

On 12-03-25 07:07 PM, Raymond Wagner wrote:
> On 3/25/2012 18:27, Joe Mythtv wrote:
>> is it possible to run a 'scan for changes' of the video library in the background? it can take
>> several minutes to run so it is obtrusive to run everytime i upload home videos to my DVR (when
>> family members want to see footage of the kids, they want it ASAP...)
>> maybe there's a way to run it only for a specific directory to which I upload files more frequently?
> 
> With a few thousand videos spread across multiple drives and arrays, performing a scan of the Video
> Library only takes me a couple seconds.  Any new content added needs to be hashed, but you're
> talking about reading 64KB from the front and back of a file.  Not something time intensive for even
> dozens of new files.  If you have the batch metadata grabber enabled, that can take some time
> churning through the new content, but that is run in the background and is going to turn up empty on
> home videos anyway.
> 
> If your scans are taking several minutes to run each time, there is something misconfigured on your
> system.  Is this content local to one of your backends, or on a remote network share?  There is a
> known issue where CIFS shares, and especially deeply nested ones, take an inordinately long time to
> scan.


The first scan after booting may take some time.
After that, the kernel will have much of it cached
for future scans, depending on VM activity.

So it's not always mere seconds.  Here, it seems to take about 30 seconds
to scan about 2400 videos.  Subsequent runs take perhaps 2-3 seconds.