Xfce Forum

rayray

Member

Registered: 2025-05-27

Posts: 4

Is XFWM causing my mouse to drop events/event process lagging?

My mouse behaves erratically with no obvious cause when using XFWM. (I first thought it was an issue with mouse acceleration, or something similar. It's hard to explain.) The output of my xorg.log shows that when this issue occurs, events are dropped and event processing is lagging significantly.

My mouse's polling rate is set to 1000Hz.

[  8723.799] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[  8724.015] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[  8724.334] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[  8724.592] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[  8725.246] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[  8725.246] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: WARNING: log rate limit exceeded (5 msgs per 30s). Discarding future messages.
[  8757.578] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: client bug: event processing lagging behind by 31ms, your system is too slow
[  8757.803] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[  8771.391] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: client bug: event processing lagging behind by 26ms, your system is too slow
[  8772.152] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: client bug: event processing lagging behind by 26ms, your system is too slow
[  8794.309] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[  8794.549] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[  8795.052] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[  8795.868] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[  8796.045] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[  8796.045] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: WARNING: log rate limit exceeded (5 msgs per 30s). Discarding future messages.
[  8796.869] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: client bug: event processing lagging behind by 24ms, your system is too slow
[  8798.000] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: client bug: event processing lagging behind by 32ms, your system is too slow
[  8798.000] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: WARNING: log rate limit exceeded (5 msgs per 60min). Discarding future messages.
[ 14974.215] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[ 14981.614] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: client bug: event processing lagging behind by 23ms, your system is too slow
[ 14981.829] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[ 15088.018] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: client bug: event processing lagging behind by 39ms, your system is too slow
[ 15094.920] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: client bug: event processing lagging behind by 35ms, your system is too slow
[ 15233.588] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[ 15235.012] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: client bug: event processing lagging behind by 32ms, your system is too slow
[ 15235.183] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: client bug: event processing lagging behind by 31ms, your system is too slow
[ 15235.183] (EE) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: WARNING: log rate limit exceeded (5 msgs per 60min). Discarding future messages.
[ 15984.037] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[ 15984.341] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[ 15984.649] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[ 15985.053] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[ 15985.340] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: SYN_DROPPED event - some input events have been lost.
[ 15985.340] (II) event3  - Corsair CORSAIR SCIMITAR RGB ELITE Gaming Mouse: WARNING: log rate limit exceeded (5 msgs per 30s). Discarding future messages.

I am using XFCE4 with XFWM with X11 on Arch Linux, my AMDGPU, Mesa and other related drivers are up to date. I have a Ryzen 9 9900X and RX 9070XT. This issue does not occur on Wayland, nor does it occur with full-screen games which I assume handle compositing themselves. I believe the issue is with XFWM, or the way my GPU/mouse are playing with XFWM. It just doesn't make sense to me and I'm unsure how to diagnose such an issue

I have been told by a friend that it's because "X11 handles rendering and input processing, and that my GPU/xfwm is blocking the X11 thread from processing the mouse event because my monitor refresh rate is 180Hz and my mouse is polling at 1000Hz", which seems silly to me.

This issue occurs randomly, but is very irritating when it does and I cannot determine its exact cause. Disabling TearFree within xrandr and VBLANK / Compositing off in xfwm4 reduces how often it happens, which leads me to further believe the issue is compositor related.

I apologize if this issue is out of the scope of this forum

CwF

Moderator

Registered: 2018-01-28

Posts: 323

Re: Is XFWM causing my mouse to drop events/event process lagging?

It is beyond Xfce and also not related to screen refresh.

My mouse's polling rate is set to 1000Hz.

In what respect is that set? The kernel needs compiled with the correct setting, or maybe set within the usbhid kernel module .

rayray

Member

Registered: 2025-05-27

Posts: 4

Re: Is XFWM causing my mouse to drop events/event process lagging?

In what respect is that set? The kernel needs compiled with the correct setting, or maybe set within the usbhid kernel module .

Good question... the kernel module is set to accept whatever the mouse is sending.

[ray@icebox ~]$ systool -m usbhid -A mousepoll
Module = "usbhid"

    mousepoll           = "0"

and the mouse is set to send at 1000Hz (1ms)

[ray@icebox ~]$ sudo grep -B3 -A6 "1b1c.*1be3" /sys/kernel/debug/usb/devices

T:  Bus=01 Lev=01 Prnt=01 Port=03 Cnt=01 Dev#=  2 Spd=480  MxCh= 0
D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
P:  Vendor=1b1c ProdID=1be3 Rev= 1.02
S:  Manufacturer=Corsair
S:  Product=CORSAIR SCIMITAR RGB ELITE Gaming Mouse
S:  SerialNumber=4B82529CC98617598187BDAD573DAF06
C:* #Ifs= 4 Cfg#= 1 Atr=a0 MxPwr=500mA
I:* If#= 0 Alt= 0 #EPs= 1 Cls=03(HID  ) Sub=01 Prot=02 Driver=usbhid
E:  Ad=82(I) Atr=03(Int.) MxPS=  64 Ivl=1ms

Anyways, since this issue is clearly out of scope, I'll stop posting here. Thank you.