Arch Linux

frumble

Member

From: Germany

Registered: 2012-05-20

Posts: 164

Website

[SOLVED] KDE (now) slows extremely down with HDMI receiver connected

Hey, I think of this more as a hardware/driver/libs issue than a problem with Plasma.
After the updates of the last weeks, my desktop is unusable slow with my HDMI receiver for Audio. I have a monitor connected via DVI-D and a separate HDMI link for only audio to my Marantz NR1504 receiver with latest firmware. I'm using the free radeon driver on a Radeon HD 7770 and the receiver is configured only as an 'overlapping' 640x480 @60 Hz monitor. Normally, I could login and everything works: Audio output (PulseAudio), and a fast system. But recently, the situation has changed: When I login, the splash animation slows down at the 'globe' and is crawling incredible slow to the two last symbols until the desktop appears. Then, everything is incredibly slow: I can only move the mouse cursor with big stuttering, autostart programs open with extreme delay, even closing my autostarted Firefox takes a good while. When switching to a tty, the PC responds fast.

I don't get what could be the problem here. Just installed a Kubuntu 14.10 to determine if it would have the same problem, then it would be perhaps a hardware issue, but no, login, audio, 'performance' etc. works just fine in this fresh Kubuntu install.
Even tried downgrading my kernel to linux-3.18.2-2 (09. January) and rolled back from the recently installed PulseAudio 6.0-1 to 5.0-1 with no luck. X-Server 1.17 came after my problems, didn't helped, even so downgrading from mesa-10.4.4.
But after powering off the receiver, I can start my system normally.
OR: When the receiver is playing from another source to the time of my login. Then I see the a little strange overlapping KDE login splash as usual (so I know, the system recognizes the receiver) but the login works nonetheless and I can later switch the source to my PC and play audio.

This gets even weirder: Sometimes, the login works as desired, my desktop responds fast and everything seems great until I happen to start one of the new KDE Applications 5 programs like the updated Konsole and Gwenview in Qt5. *Sometimes*, this causes the exact same strange performance slowdown of all graphical things (but only if the receiver is on). When I have much patience and get the session to log me out to return to the KDM login screen, even *there* everything is slow as crap and even so when I kill and restart the X-Server the hard way.
So, I don't have any idea left about what could cause this. Here is my pacman log. Would very appreciate your help!

Last edited by frumble (2015-02-21 20:03:59)

frumble

Member

From: Germany

Registered: 2012-05-20

Posts: 164

Website

Re: [SOLVED] KDE (now) slows extremely down with HDMI receiver connected

I was able to pipe out the output of dmesg after a successful login and a triggering of the slow down after the start of Qt5 Kate. The last lines are full of

[drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is xxx

Strange. Maybe the issue is because I have no monitor plugged into my HDMI receiver but do use it just for audio?

[drm:radeon_dvi_detect] *ERROR* HDMI-A-1: probed a monitor but no|invalid EDID

  This seems like that. But again, it was working just a few weeks ago and the other distro doesn't have this bug.

frumble

Member

From: Germany

Registered: 2012-05-20

Posts: 164

Website

Re: [SOLVED] KDE (now) slows extremely down with HDMI receiver connected

Hey, I got the solution!
Had to connect a real monitor via HDMI into my receiver and then to read out the correct EDIDs via get-edid. Now I had 'correct' EDIDs of a monitor in this file and could enforce it in boot even without this HDMI monitor really plugged into the receiver. My segment in /etc/default/grub is "drm_kms_helper.edid_firmware=HDMI-A-1:edid/edid-hdmi-only.bin". – Without the HDMI specifier my DVI-D monitor with the higher resolution won't show a signal.
Now all my KDE Plasma starting problems, the strange slow down of everything with the connected receiver after the login and slow downs after starting a Qt 5 program are gone! Still odd that this problem came out of nowhere and other distros tested still work without this workaround.

Last edited by frumble (2015-02-21 20:23:17)