Ubuntu 20.04 becomes super slow

My Ubuntu becomes extremely slow suddenly. When I reboot it works for a while and then it becomes super slow again.

I have a Dell lattitude 7400 connected to a DisplayLink D6000

It happens mostly when the Dock is plugged but not only.

For example, during the indexing of files in PHPStorm, my computer is unusable. Here is the htop during ex htop

Here are some logs I could find when it starts to be slow :

/var/log/syslog

Jun  7 11:49:59 bastio-Latitude-7400 wpa_supplicant[948]: wlo1: CTRL-EVENT-SIGNAL-CHANGE above=1 signal=-44 noise=9999 txrate=866700
Jun  7 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): EDID vendor "AUO", prod id 25405
Jun  7 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Printing DDC gathered Modelines:
Jun  7 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Modeline "1920x1080"x0.0  141.00  1920 1936 1952 2104  1080 1083 1097 1116 +hsync -vsync (67.0 kHz eP)
Jun  7 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Modeline "1920x1080"x0.0  112.80  1920 1936 1952 2104  1080 1083 1097 1116 +hsync -vsync (53.6 kHz e)
Jun  7 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): EDID vendor "AUO", prod id 25405
Jun  7 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Printing DDC gathered Modelines:
Jun  7 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Modeline "1920x1080"x0.0  141.00  1920 1936 1952 2104  1080 1083 1097 1116 +hsync -vsync (67.0 kHz eP)
Jun  7 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Modeline "1920x1080"x0.0  112.80  1920 1936 1952 2104  1080 1083 1097 1116 +hsync -vsync (53.6 kHz e)
Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.502949] evdi: [D] evdi_detect:94 (dev=0) poll connector state: disconnected
Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.503007] evdi: [D] evdi_detect:94 (dev=0) poll connector state: disconnected
Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.503048] evdi: [D] evdi_detect:90 (dev=1) poll connector state: connected
Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.503055] evdi: [D] evdi_painter_get_edid_copy:242 (dev=1) EDID valid
Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.503721] evdi: [D] evdi_detect:90 (dev=0) poll connector state: connected
Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.503727] evdi: [D] evdi_painter_get_edid_copy:242 (dev=0) EDID valid
Jun  7 11:51:43 bastio-Latitude-7400 systemd[1]: Starting Cleanup of Temporary Directories...
Jun  7 11:51:44 bastio-Latitude-7400 systemd[1]: systemd-tmpfiles-clean.service: Succeeded.
Jun  7 11:51:44 bastio-Latitude-7400 systemd[1]: Finished Cleanup of Temporary Directories.
Jun  7 11:51:55 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 7 threads of 3 processes of 1 users.
Jun  7 11:53:42 bastio-Latitude-7400 rtkit-daemon[1162]: message repeated 9 times: [ Supervising 7 threads of 3 processes of 1 users.]
Jun  7 11:53:42 bastio-Latitude-7400 rtkit-daemon[1162]: Successfully made thread 5669 of process 5541 owned by '1000' RT at priority 10.
Jun  7 11:53:42 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
Jun  7 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: message repeated 10 times: [ Supervising 8 threads of 4 processes of 1 users.]
Jun  7 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Successfully made thread 5856 of process 5718 owned by '1000' RT at priority 10.
Jun  7 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 9 threads of 5 processes of 1 users.

journalctl -f

juin 07 11:48:01 bastio-Latitude-7400 gnome-shell[2748]: Window manager warning: WM_TRANSIENT_FOR window 0x2000670 for 0x20006a6 window override-redirect is an override-redirect window and this is not correct according to the standard, so we'll fallback to the first non-override-redirect window 0x200004c.
juin 07 11:48:23 bastio-Latitude-7400 gnome-shell[2748]: Could not create selection source for X11: Le format TARGETS n'est pas pris en charge
juin 07 11:49:11 bastio-Latitude-7400 wpa_supplicant[948]: wlo1: CTRL-EVENT-SIGNAL-CHANGE above=1 signal=-49 noise=9999 txrate=866700
juin 07 11:49:12 bastio-Latitude-7400 gnome-shell[2748]: Could not create selection source for X11: Le format TARGETS n'est pas pris en charge
juin 07 11:49:45 bastio-Latitude-7400 gnome-shell[2748]: Could not create selection source for X11: Le format TARGETS n'est pas pris en charge
juin 07 11:49:53 bastio-Latitude-7400 gnome-shell[2748]: Window manager warning: WM_TRANSIENT_FOR window 0x2000c94 for 0x2000ca7 window override-redirect is an override-redirect window and this is not correct according to the standard, so we'll fallback to the first non-override-redirect window 0x200004c.
juin 07 11:49:59 bastio-Latitude-7400 wpa_supplicant[948]: wlo1: CTRL-EVENT-SIGNAL-CHANGE above=1 signal=-44 noise=9999 txrate=866700
juin 07 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): EDID vendor "AUO", prod id 25405
juin 07 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Printing DDC gathered Modelines:
juin 07 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Modeline "1920x1080"x0.0  141.00  1920 1936 1952 2104  1080 1083 1097 1116 +hsync -vsync (67.0 kHz eP)
juin 07 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Modeline "1920x1080"x0.0  112.80  1920 1936 1952 2104  1080 1083 1097 1116 +hsync -vsync (53.6 kHz e)
juin 07 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): EDID vendor "AUO", prod id 25405
juin 07 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Printing DDC gathered Modelines:
juin 07 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Modeline "1920x1080"x0.0  141.00  1920 1936 1952 2104  1080 1083 1097 1116 +hsync -vsync (67.0 kHz eP)
juin 07 11:51:02 bastio-Latitude-7400 /usr/lib/gdm3/gdm-x-session[2313]: (II) modeset(0): Modeline "1920x1080"x0.0  112.80  1920 1936 1952 2104  1080 1083 1097 1116 +hsync -vsync (53.6 kHz e)
juin 07 11:51:02 bastio-Latitude-7400 kernel: evdi: [D] evdi_detect:94 (dev=0) poll connector state: disconnected
juin 07 11:51:02 bastio-Latitude-7400 kernel: evdi: [D] evdi_detect:94 (dev=0) poll connector state: disconnected
juin 07 11:51:02 bastio-Latitude-7400 kernel: evdi: [D] evdi_detect:90 (dev=1) poll connector state: connected
juin 07 11:51:02 bastio-Latitude-7400 kernel: evdi: [D] evdi_painter_get_edid_copy:242 (dev=1) EDID valid
juin 07 11:51:02 bastio-Latitude-7400 kernel: evdi: [D] evdi_detect:90 (dev=0) poll connector state: connected
juin 07 11:51:02 bastio-Latitude-7400 kernel: evdi: [D] evdi_painter_get_edid_copy:242 (dev=0) EDID valid
juin 07 11:51:43 bastio-Latitude-7400 systemd[1]: Starting Cleanup of Temporary Directories...
juin 07 11:51:44 bastio-Latitude-7400 systemd[1]: systemd-tmpfiles-clean.service: Succeeded.
juin 07 11:51:44 bastio-Latitude-7400 systemd[1]: Finished Cleanup of Temporary Directories.
juin 07 11:51:55 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 7 threads of 3 processes of 1 users.
juin 07 11:51:55 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 7 threads of 3 processes of 1 users.
juin 07 11:52:59 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 7 threads of 3 processes of 1 users.
juin 07 11:52:59 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 7 threads of 3 processes of 1 users.
juin 07 11:53:04 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 7 threads of 3 processes of 1 users.
juin 07 11:53:04 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 7 threads of 3 processes of 1 users.
juin 07 11:53:42 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 7 threads of 3 processes of 1 users.
juin 07 11:53:42 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 7 threads of 3 processes of 1 users.
juin 07 11:53:42 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 7 threads of 3 processes of 1 users.
juin 07 11:53:42 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 7 threads of 3 processes of 1 users.
juin 07 11:53:42 bastio-Latitude-7400 rtkit-daemon[1162]: Successfully made thread 5669 of process 5541 owned by '1000' RT at priority 10.
juin 07 11:53:42 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
juin 07 11:55:26 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
juin 07 11:55:26 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
juin 07 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
juin 07 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
juin 07 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
juin 07 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
juin 07 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
juin 07 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
juin 07 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
juin 07 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 8 threads of 4 processes of 1 users.
juin 07 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Successfully made thread 5856 of process 5718 owned by '1000' RT at priority 10.
juin 07 11:57:27 bastio-Latitude-7400 rtkit-daemon[1162]: Supervising 9 threads of 5 processes of 1 users.

/var/log/kern.log

Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.502949] evdi: [D] evdi_detect:94 (dev=0) poll connector state: disconnected
Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.503007] evdi: [D] evdi_detect:94 (dev=0) poll connector state: disconnected
Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.503048] evdi: [D] evdi_detect:90 (dev=1) poll connector state: connected
Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.503055] evdi: [D] evdi_painter_get_edid_copy:242 (dev=1) EDID valid
Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.503721] evdi: [D] evdi_detect:90 (dev=0) poll connector state: connected
Jun  7 11:51:02 bastio-Latitude-7400 kernel: [  864.503727] evdi: [D] evdi_painter_get_edid_copy:242 (dev=0) EDID valid

UPDATE: I am on a dualBoot, when i use the computer on windows I don't get any error.

System "freezes" are often caused by running too many, too large programs and running out of available memory. Use free to see if you have swap space, read man mkswap swapon fstab to create some. Swap space must be contiguous. use mkswap or fallocate, not dd. Traditionally, swap space of 1.5 × RAM has been recommended, but YMMV. If you don't plan to hibernate your system, you can have less than 1.0 × RAM.

You can try to switch your laptop to performance mode it is explained how to do this in this thread:

Setting to High Performance

for me it only work for some time after booting my system. My laptop even when every core is using 100% is very quiet and this is strange for me. Did you maybe solved your problem somehow different?