Bug 291563

Summary: apper blocks plasma (with dbus call)
Product: [Applications] apper Reporter: S. Burmeister <sven.burmeister>
Component: generalAssignee: Daniel Nicoletti <dantti12>
Severity: normal CC: bluelightning, danielstefanmader+kde, germano.massullo, kde, kevin.kofler, lindsay.mathieson, rdieter, rifter0x0000, rtguille, sfranzen85, spamsuxx, toddrme2178
Priority: NOR    
Version: unspecified   
Target Milestone: ---   
Platform: openSUSE   
OS: Linux   
Latest Commit: Version Fixed In: 0.7.2

Description S. Burmeister 2012-01-15 09:07:22 UTC
Version:           unspecified (using Devel) 
OS:                Linux

Everytime dbus checks for updates plasma freezes for up to 20-30 seconds. With an unstable wlan/internet connection, i.e. some network calls timing out it happens every few minutes.

A frozen plasma results in it not accepting any clicks, not opening any pop-ups etc.

Confirmed by multiple users on openSUSE and Kubuntu, e.g. bug 287002 comment 73 and 80.

Stopping apper's update monitor via systemsettings or killing the sentinel processes solves the problem. Happens with 4.7 and 4.8.

Reproducible: Always

Steps to Reproduce:
Start apper's update monitor
Wait until it updates

Actual Results:  
Plasma freezes

Expected Results:  
No freeze
Comment 1 S. Burmeister 2012-01-21 10:27:44 UTC
According to bug 287002#c84 the blocking only happens if the wireless network is enabled. Yet it's definitely apper causing it since the freezes do not happen if apper is disabled.
Comment 2 Daniel Nicoletti 2012-02-17 00:26:03 UTC
Can someone please try Apper from git? I changed some blocking code that should block kded (not plasma) bug... who knows if this wasn't the reason since the network applet AFAIK talks to kded...
Comment 3 Christoph Feck 2012-02-18 15:38:35 UTC
*** Bug 287002 has been marked as a duplicate of this bug. ***
Comment 4 Reartes Guillermo 2012-03-05 12:23:32 UTC
For me, it happens when i insert an usb 3g modem. 
I have to wait aproximatelly 20 seconds to click any part of the panel, basically, i cannot use the panel until the modem is ready to be dialed in  by NM.

Fedora 16 X86_64 (KDE 4.7.4)

NetworkManager.x86_64   1:0.9.2-1.fc16
device-mapper.x86_64    1.02.65-6.fc16
Comment 5 Daniel Nicoletti 2012-04-03 00:56:05 UTC
I have changed Apper daemon to not do blocking calls but NetworkManager is also guilt of doing some of those too, so please try Apper from git and report if the error is gone.
Comment 6 S. Burmeister 2012-05-06 08:29:15 UTC
Seems better with 0.7.1. Still there are two apper-sentinel processes started when logging into KDE.
Comment 7 Germano Massullo 2012-05-15 07:12:59 UTC
Is there a way to disable Apper? Every single time I boot my desktop computer, KDE freezes for 20 seconds, so we can find out a lot of things if we manage to disable apper and not letting it freeze the boot process
Comment 8 Rex Dieter 2012-05-15 11:08:50 UTC
Options include:
1.  uninstall apper
2.  systemsettings -> startup&shutdown -> service manager -> uncheck apper monitor
3.  apper -> click wrench (on right) -> settings -> check for updates: never (though this might not completely stop it)
Comment 9 Blackpaw 2012-05-18 11:14:54 UTC
I don't have apper installed but I have the exact same symptoms - plasma freezes for a good 20+ seconds until my wirless connects.

Kubuntu 12.04, kde 4.8.3
Comment 10 Daniel Nicoletti 2012-05-18 13:42:06 UTC
Apper was fixed not to block (the next version will even use Thread so people stop blaming it)
The issue as I told before is that networkmanager should stop doing sync, imo it should also use a thread in KDED to avoid locking other stuff in kde...
Comment 11 kde 2012-05-23 15:48:33 UTC
I have the same problem and I don't have apper installed
Kubuntu 12.04 and KDE 4.8.3

The plasma remains locked indefinitely until in System Monitor I send Interrupt signal. That works once. The next time it doesn't work anymore and the plasma will remain locked.
Comment 12 Daniel Nicoletti 2012-05-23 15:50:21 UTC
This issue was also caused by NetworkManager,
and Apper 0.7.2 doesn't has this anymore since it
uses now a separate thread now.
Comment 13 Bjoern Olausson 2012-12-10 20:31:12 UTC
I am experiencing this bug in KDE  4.9.3, 4.9.4 and  KDE networkmanagement widget

When I use network networkmanagement widget to establish a VPN connection, and the connection is abnormally terminated or has server lags, the entire KDE GUI seems to freeze. After a couple of seconds (20-30) the GUI is responsive for a short time and freezes then again.

To solve this I have to kill X. I never had the patience to wait for the GUI to recover.

No "Apper" installed by the way

So this bug might be a regression?

Comment 14 Daniel Nicoletti 2012-12-10 20:42:44 UTC
I don't think it's a regression.
All Apper code got moved to a thread to avoid
this kinds of blocks (which a few were due to a combination with network manager).
On the other hand Network Manager just changed most
of it's code just to be async, but not all, so I bet you are
hitting the part that is still blocking, please report a new
but against network manager, since this bug was about Apper.
Comment 15 Bjoern Olausson 2012-12-10 20:58:58 UTC
Thanks for the fast response.

I added bug #311484