0007580: MTP Synchronization takes ~5-10s to initiate (regression) - MantisBT

ID	Project	Category	View Status	Date Submitted	Last Update

0007580	MMW v4	Synchronization	public	2011-03-24 15:35	2011-04-07 19:20

Reporter	rusty	Assigned To
Priority	urgent	Severity	major	Reproducibility	always
Status	closed	Resolution	fixed
Product Version	4.0
Target Version	4.0	Fixed in Version	4.0

Summary	0007580: MTP Synchronization takes ~5-10s to initiate (regression)
Description	In build 1356, whenenever an autosync is initiated to an MTP device, it takes ~5-10 seconds before any sync activity begins (or at least appears to begin as evidenced by the status bar). This leads the user to believe that the sync button isn't working.
Tags	No tags attached.
Attached Files	bug_7580_debug_log.zip (161,726 bytes)

Fixed in build	1359

jiri 2011-03-25 10:43 administrator ~0023891	I don't see any difference, sync starts immediately here. Are you sure it's a regression, isn't it a scanning of a quite large device? Maybe a debug log would help to clarify (with indication of when does which action begin).

rusty 2011-03-25 14:11 administrator ~0023894	Upon further testing, I think that the bug is actually a UI bug (UI redrawing is holding up the initiation of synchronization), and that it might be related to issue 0007586. Here is a video of the issue: http://www.screencast.com/users/rustymonkey/folders/Jing/media/1f3e7199-848e-4ce7-9d3c-e98f7fed9476 Debug log is attached as well.

rusty 2011-03-25 14:17 administrator ~0023895	Follow up: there's definitely a UI bug, but the delay is specific to MTP devices. i.e. when I do the exact same test with an iPod, there's only a ~1s delay.

jiri 2011-03-25 14:58 administrator ~0023898	It's apparent from the video that the problem is in showing the in-place device config dialog. The debug log doesn't show any clear reason for the slowdown though. In case we can't find any reason, some debug messages could be added to showing of the dialog. I wonder whether it couldn't be e.g. retrieval of device total&free space? All such actions should be done only after the dialog is shown in order to avoid any such problems.

Ludek 2011-03-28 22:22 developer ~0023956 Last edited: 2011-03-28 22:46	Added useful debug strings in build 1359. My expectation is that this regression is related to Supported formats reading (related to issue 0007595) and I also probably found the problem in the code and fixed in build 1359 althoug on my DB the performance glitch wasn't so critical so there might be something else.

rusty 2011-04-07 19:20 administrator ~0024114	This is resolved in 1361.