KDE 17.3 Rosa - Slow boot with network

[darudey]

Running 64-bit Mint KDE 17.3

A fresh install on a SSD without network (with auto-login enable) boots and load the KDE desktop in about 12 seconds - which is fantastic!

As soon as the ethernet cable is plugged in, the KDE boot splash screen (the one with the Linux Mint 17.3 background wallpaper) adds an extra 20 seconds delay.

My first suspicion is that this is related to IPv6, so I disabled it in the KDE Connection Editor and in /etc/sysctl.conf. ifconfig shows no IPv6 address.

But this does not fix the 20 seconds delay.

Does anyone have any further ideas? It's a fresh install, latest updates with Thunderbird and Chrome installed.

[darudey]

Hi all,

I narrowed it down to something related to connecting to a wired network.

In the Network Manager -> General tab, if I uncheck 'Automatically connect to this network when it is available', I get pass the login / splash screen without any delay.

However, when I attempt to connect to the network, it takes 20-22 seconds to do so. I wonder what it is blocking / waiting for.
Even if I set a manual IP, I still see the same delay.

[darudey]

Hi,

Perhaps this needs to be moved to the 'Networking' sub-forum, but I managed to shave off 10 seconds by disabling dnsmasq:

Code: Select all

/etc/NetworkManager/NetworkManager.conf

[main]
;dns=dnsmasq

My syslog now shows a 10 second delay between, at 10:11:02, my eth0 is already up with DHCP

Code: Select all

10:11:02 NetworkManager: <info> Writing DNS information to /sbin/resolveconf
10:11:12 dbus: [system] Activating service name='org.freedesktop.RealtimeKit1' (using servicehelper)

I'd still like to know how to reduce the delay even further.

[phd21]

HI "darudey",

That's still pretty darn fast even with a 10-20 second delay. Mine always takes that amount of time, on my older antiquated computer hardware. It would seem weird too me that connecting the wired Ethernet cable would make a longer than normal delay (and I am not stating that it is). Do you also have a wireless connection ability? Did you experience any abnormal delay with a wireless connection? Have you tried a different Ethernet cable? Maybe the router and that cable have a problem. Cat5 vs Cat6, shielded vs non-shielded? You could tell your router to use a static IP address for this computer, then change the Network Manager Icon settings for your ISP connection to use the static IP.

You could try changing your ISP connection's DNS server IP addresses to those by another DNS server provider which is a smart thing to do anyway for your own Internet security. I use "openNic", and there are a few others like, "OpenDNS", "dnswatch, Google, Comodo, etc...

I'm not sure if disabling "dnsmasq" the way you did may adversely affect other things. or not? The "dsnmasq" daemon is not loaded automatically. You can check the Software Manager or Synaptic Package Manager (SPM) to make sure that "dnsmasq" is not loaded. It is not loaded by default on my KDE, even though other dnsmasq libraries are installed.

From the output, it look as if the KDE desktop was trying to load the "freedesktop" which if you do not use it, in the system menu under account details, on social desktop, uncheck it. If you are not using bluetooth, then under system settings, under Startup and Shutdown, then Service Manager, you can also disable Bluetooth and Bluetooth file transfer.

I disabled IPv6 as well, but I chose to update the grub Linux command line method,
GRUB_CMDLINE_LINUX="ipv6.disable=1"
and to edit the "sudo gedit /etc/gai.conf" to give preference to IPv4, See article in link below.

Disable ipv6 if its not supported
http://www.blackmoreops.com/2015/08/04/ ... -in-linux/

Good luck ...

Hope this helps ...

[darudey]

Thanks phd21,

I followed everything you suggested this morning, but unfortunately it didn't help reduce the delay, but I learnt many things - so thank you! I previously had ipv6 disabled in /etc/sysctl.conf.

I narrowed down the problem to this (writing DNS information):

Code: Select all

10:11:02 NetworkManager: <info> Writing DNS information to /sbin/resolveconf
10:11:12 dbus: [system] Activating service name='org.freedesktop.RealtimeKit1' (using servicehelper)
10:11:12 NetworkManager: <info> Activation (eth0) successful, device activated

From my understanding, /sbin/resolveconf is a shell script file used by NetworkManager to populate /etc/resolv.conf, unless there's more to it than that?
I moved /sbin/resolveconf and replaced it with a blank file. Now the KDE desktop loads instantly, without any delay.

I also restored the dnsmasq line I previously commented out from NetworkManager.conf.

My use case is a very simple ipv4 wired ethernet connection to my router.
Now, I'd like to understand the root cause for the delay in /sbin/resolveconf.

[phd21]

Hi "darudey",

You are welcome.

You could search the Internet for "Linux Mint KDE + resolv.conf", or "Linux Mint KDE + /sbin/resolveconf", or some search criteria like these to see what you can find.

You could also create a new post in the "Networking" section, and reference this post as well. Keep in mind that it can take some time for people to reply, depending on the complexity of the topic.

Good Luck .... Keep us posted on what you find out.

[darudey]

Hi phd21,

After a lot of digging, the problem is further narrowed down to...

/sbin/resolveconf -> /etc/resolvconf/update.d/libc -> /etc/resolvconf/update-libc.d/avahi-daemon -> /usr/lib/avahi/avahi-daemon-check-dns.sh -> last 4 lines of that file, I commented out enable_avahi (which calls invoke-rc.d avahi-daemon start)

I also noticed this exact problem occurs in Kubuntu 14.04 LTS 64-bit.

By the way, this doesn't appear to stop avahi from running, but it does get rid of the delay.

[Mr.October]

Hi, some installations ago I also had this problem, booting took a really long time. Found out it had to do with the order in which hosts are found.
On this page http://www.tldp.org/LDP/solrhe/Securing ... sec92.html a sample is shown for the /etc/host.conf file. I now have the same order in my file and booting is pretty fast. Look at the line marked with 1.

[darudey]

Thanks Mr.October, I checked the /etc/host.conf but found that tweaks there doesn't make any difference.

It's a shame, I installed 4 fresh copies of KDE 17.3 and on all 4 machine (with slightly different CPU and motherboard) I had to comment out the same line in /usr/lib/avahi/avahi-daemon-check-dns.sh to get rid of the >10 seconds delay.

I can't find much a bug or report online to pinpoint this exact problem (delay calling invoke-rc.d avahi-daemon start).
But I'm sure I'm not the first to discover it!

This is the closest bug I could find:-
https://bugs.debian.org/cgi-bin/bugrepo ... bug=559927