833035 - [mediadb] begin metadata parsing immediately when there is no last scan time.

Status: RESOLVED DUPLICATE of bug 814178

(Firefox OS Graveyard :: Gaia, defect)

Description

[James Lal [:lightsofapollo]]

In media db when there is no database we wait until file enumeration (device storage) is complete then begin parsing. The time between each cursor iteration can be significant so we effectively block until the entire request is complete to begin parsing.


Here is a short snippet of time between iterations (this is on a very small set of data imagine something like 500 images). Each number is the time between the last and current iteration.

[65,11,21,12,7,5,5,7,5,8,5,4,6,5,6,5,7,4,6,6,5,6,6,4,6,6,6,6,6,5,7,6,10,6,15,23,4,6,7,6]

David suggested that we can improve this by always running a "quickScan" if lastScanTime is not present. This should greatly reduce the amount of time it takes for the user to see the first image/video/music file when they have a fairly large number of media assets.

Comment 1

[James Lal [:lightsofapollo]]

With my reference files we are spending somewhere between 10 and 15 seconds in device storage loading the 500 images and 703 music files. As this are we wait until the end of this 10-15 seconds before parsing even the first file.

Comment 2

[David Flanagan [:djf]]

James,

Thanks for identifying this optimization. Bug 814178 is tef+ to speed up the music app scanning. I'll probably fix this bug as part of that one.

Comment 3

[James Lal [:lightsofapollo]]

Re-assigning... David has a fix for this in his music patch.

Comment 4

[James Lal [:lightsofapollo]]

https://github.com/mozilla-b2g/gaia/commit/ebac3046280299ec320ecae04ca5c34a163bc3eb

Fixed in related bug (https://bugzilla.mozilla.org/show_bug.cgi?id=814178)