Bug 359661

When you open Kickoff ("the start menu") and hover entries there, do you also only have every second item highlighted as you move around? If so, this is a driver issue.

Yep, exactly so!

the higlight happens only on second item, good catch. What driver are you referring to? video card? something in mesa layer?

Many thanks for the answer!

Same issue here
I use Debian Stretch and Plasma 5

After a while, the issue is reappeared. I don't think is related to xf86-intel driver (I'm on 2.99.917 and I've also tried to downgrade it).

Now I'm on plasma 5.7.1 (same behaviour on 5.7.0), gentoo packages. I can provide all information required or try different versions of packages, just let me know.

I can confirm this behavior on plasma 5.5.5. It appears it's also been reported elsewhere: https://bugzilla.redhat.com/show_bug.cgi?id=1307178

I can confirm this behavior on Plasma 5.6.5 (using backports PPA on Kubuntu 16.04). The clock widget only seems to update once every two seconds. Occasionally it'll show two consecutive seconds. My usual display is 24-hour time with seconds and long date, e.g.

16:10:26
Tuesday, July 26, 2016

I thought maybe it might have something to do with the fact that I normally have two clock widgets, one at the right edge of the bottom panel on each of my two monitors, but I removed one of the clocks and the other clock still only updates every ~2 seconds or so.

Also, Plasmashell is currently using about 30% CPU according to GNU top. (By contrast, on my old 14.04 machine, plasma-desktop is currently using about 0.7% CPU.) I killed plasmashell (with "kdequitapp5 plasmashell") and then ran plasmashell & again, and now it's using around 1% CPU, and the clock widget is updating every second.

So it looks like it's not a bug with the clock per se, but the fact that Plasmashell eventually decides to just start chewing up tons of CPU for no apparent reason.

(I'm now at Plasma 5.6.5.1)

(In reply to kde from comment #6)
>
> Also, Plasmashell is currently using about 30% CPU according to GNU top. [...]
> I killed plasmashell (with "kdequitapp5 plasmashell") and then
> ran plasmashell & again, and now it's using around 1% CPU, and the clock
> widget is updating every second.
> 
> So it looks like it's not a bug with the clock per se, but the fact that
> Plasmashell eventually decides to just start chewing up tons of CPU for no
> apparent reason.

I get the second-skipping behavior even when plasma eats no discernible amount of cpu resources. So although this may also cause this issue, or exacerbate it, it cannot be the root cause.

(In reply to Fabio Coatti from comment #4)
>
> xf86-intel driver (I'm on 2.99.917 [...]).

N.B.: I'm using the same driver and also have the entry-skipping behavior.

Do all affected people use the (this?) intel driver?

(In reply to Erik Quaeghebeur from comment #8)
> (In reply to Fabio Coatti from comment #4)
> > xf86-intel driver (I'm on 2.99.917 [...]).
> 
> N.B.: I'm using the same driver and also have the entry-skipping behavior.
> Do all affected people use the (this?) intel driver?

Yeah, I'm using that same driver too.

*** This bug has been marked as a duplicate of bug 353983 ***

I tried to remove xf86-intel driver completely, relying on kms setup, and the issue disappeared. I don't really know what are the drawbacks, maybe the grpahics (not really sure, though) are a bit slower but for my usage it is fine.

(In reply to David Edmundson from comment #10) 
> 
> *** This bug has been marked as a duplicate of bug 353983 ***

David, I don't see how this is a duplicate. Can you explain?