19.04 apps start taking 30s to respond after a varying amount of time

[ksdsksd]

Hi all. I'm having a frustrating issue... After varying(1,2-10-20) hours of use, certain applications take either 30 seconds to run or to open a file. The only way to fix this is to reboot(i've tried killing X and re-logging in).

The main programs affected by this are Firefox(30s on launch), open office(30s when opening a file(even when cached)), sudo and other command line apps are affected as well. Also development tools Godot & intellij Exhibit it when running what i'm developing(especially with these adding 30 seconds to a 3 second compile and run time is extremely annoying!)

Typically all these things take < 3 seconds.

My system is a FX8350 8 core @ 4Ghz, 16Gb ram, MSI mobo, with a 240Gb ssd, and 2x 1Tb hdds, and a nvidia Gtx 1050ti.

ksysguard shows the cpu usage at 1% and memory <10Gb when it happens.

yes it is up to date.

Does anyone have any suggestions on what might be causing this, or where to look, since its intermittent. I've used Kubuntu for the last 8 - 10 years, my laptop, and my wife's has 18.04 on them(never had this problem though).

[Don B. Cilly]

ksysguard shows the cpu usage at 1% and memory <10Gb when it happens.

Well, isn't that quite the mystery then.
In my limited experience, when that sort of thing happens, CPU or memory usage or both tend to be very high.
So I'm afraid I can't help... except...

... you could try getting a comprehensive conky monitor.
This one is the most compact and informative I know of.
It needs some adjusting, but if you have conky-all (with LUA bindings), curl and inxi installed it should work. Not very well aligned - it doesn't align the same on two screens - but work it should.

And in case it's the GPU, since you have an nvidia one, you can add these two lines just before the "TOP PROCESSES" one:
${alignr}${color 80a8a4}${execbar nvidia-settings -q GPUUtilization | awk '/Attribute/ {print substr($4,10,2)}'}
${alignc}${voffset -15} GPU%

You might try the line
nvidia-settings -q GPUUtilization | awk '/Attribute/ {print substr($4,10,2)}'

in a terminal first and adjust the $s accordingly.

So why conky and not sysguard? It's there all the time, makes it easier to spot things.
Even if it doesn't help in this case, it's a good thing to have :·)

[jlittle]

Using top or htop in a konsole might give you a better picture of the overall state. In particular, check if the load average matches the CPU usage matches what ksysguard reports.

10 GB is a lot, I wonder what is taking all of that. You can have an out of memory situation that makes the system stagger, but by the time your tools get to run, maybe 30 s later, they don't see the cause, because it's reduced its memory usage, or been killed. Firefox would do that to me (years ago now) if I opened a lot of Google groups tabs with prodigal javascript; working out the cause was difficult.

Here's a couple of causes of slow downs that might not show up in monitoring tools:

• If a process (or processes) has (or have) gone rogue spawning processes or threads, that die too quickly to be seen. This problem can be noticed in a top display sometimes.
• Linux I/O scheduler problems. I had a system that froze completely at times. These can occur if something is doing a lot of I/O, perhaps legitimately, particularly to USB devices. They're very system dependent, in that the very same processing on two systems can differ drastically. However, I think you'd be aware of something doing a lot of I/O.

[Don B. Cilly]

Right, but wouldn't something like this give you an even better picture of the overall state?

[claydoh]

A small thing to check is to see if you are using swap. Even with tons of ram, some systems seem to like hitting swap a bit aggressively, and early. This would slow hard drive access down to a crawl when it happens, even if whatever was spiking the ram has stopped.


If this is happening, the swap's aggressiveness can be adjusted
https://help.ubuntu.com/community/Sw...I_change_it.3F

[ksdsksd]

Thanks for all the suggestions... Swap aggressiveness was already turned down, memory was always less than 10Gb from what was running. When i'd set this computer up i'd copied everything from my laptop's home folder. I've also had a gtx 550 ti video card prior to this one(now in my son's computer). I also had installed multiple desktops(lxde, lxqt, gnome) to see if it was a plasma issue or system wide, witch messed up other things (example: when using fullscreen on 2nd monitor the clock time would change by random amount of hours and stop running.)

So i'm guessing it may have been one or a combination of those things.
I ended up doing a fresh install, personal settings and all. Current uptime is 4 days 20:07 and no issues(as it should be).

[dagmann]

Might have been one or more applications logging.