After some digging I found that: - Fedora 40 suffers from the same issue - Mac Xquartz suffers with the same problem - it can be reproduced with any hardware and even on Virtual Box machine - bisecting the versions I dated it between 23.10 and 24.04
By doing the following test, I believe that the culprit is the ssh x11 tunneling I've enabled the X11 "tcp" (listen tcp) incoming connections on my client machine and when I connect to the remote server I've tried client $ ssh -XY remote-machine remote $ time xterm -e date real 0m5.145s user 0m0.034s sys 0m0.038s remote $ export DISPLAY=client:0.0 remote $ time xterm -e date real 0m0.136s user 0m0.032s sys 0m0.039s The effect is an important slowdown on any X11 commuication over ssh, making practically working impossible. It started to affect many people in our group -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/2077612 Title: Slow X11 performance through ssh Status in xorg-server package in Ubuntu: New Bug description: Running remote X11 applications (more pronounced on those built on top of python-tk or tcl/tk) connected through ssh -CXY in the recent 24.04 resulted in extremely slow performance, which makes it almost impossible to work. My computer that is affected, was based on xubuntu 20.04LTS and upgraded constantly up to 24.04LTS For testing, I prepared USB sticks and boot on them (Try ubuntu) so as to have a clean system Look the following screen recording https://youtu.be/KYZn3rbFduI The first time I am trying with lubuntu 24.04LTS USB stick The second time with xubuntu 20.04LTS USB stick the difference in performance is visible. ProblemType: Bug DistroRelease: Ubuntu 24.04 Package: xorg 1:7.7+23ubuntu3 ProcVersionSignature: Ubuntu 6.8.0-41.41-generic 6.8.12 Uname: Linux 6.8.0-41-generic x86_64 ApportVersion: 2.28.1-0ubuntu3.1 Architecture: amd64 BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log' CasperMD5CheckResult: unknown CompositorRunning: None CurrentDesktop: i3 Date: Thu Aug 22 11:19:27 2024 DistUpgraded: 2024-06-03 14:19:47,372 DEBUG migrateToDeb822Sources() DistroCodename: noble DistroVariant: ubuntu DkmsStatus: virtualbox/7.0.16, 6.8.0-39-generic, x86_64: installed virtualbox/7.0.16, 6.8.0-41-generic, x86_64: installed ExtraDebuggingInterest: Yes, if not too technical GraphicsCard: NVIDIA Corporation TU104GL [Quadro RTX 4000] [10de:1eb1] (rev a1) (prog-if 00 [VGA controller]) Subsystem: NVIDIA Corporation TU104GL [Quadro RTX 4000] [10de:12a0] InstallationDate: Installed on 2021-12-02 (994 days ago) InstallationMedia: Xubuntu 20.04.3 LTS "Focal Fossa" - Release amd64 (20210819.1) MachineType: ASUS System Product Name ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-6.8.0-41-generic root=UUID=6fe1f015-c88c-47ad-8b06-2ddd0ce2fc05 ro quiet splash vt.handoff=7 SourcePackage: xorg Symptom: display UpgradeStatus: Upgraded to noble on 2024-06-03 (80 days ago) dmi.bios.date: 10/27/2021 dmi.bios.release: 12.3 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 1203 dmi.board.asset.tag: Default string dmi.board.name: Z590 WIFI GUNDAM EDITION dmi.board.vendor: ASUSTeK COMPUTER INC. dmi.board.version: Rev 1.xx dmi.chassis.asset.tag: Default string dmi.chassis.type: 3 dmi.chassis.vendor: Default string dmi.chassis.version: Default string dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr1203:bd10/27/2021:br12.3:svnASUS:pnSystemProductName:pvrSystemVersion:rvnASUSTeKCOMPUTERINC.:rnZ590WIFIGUNDAMEDITION:rvrRev1.xx:cvnDefaultstring:ct3:cvrDefaultstring:skuSKU: dmi.product.family: To be filled by O.E.M. dmi.product.name: System Product Name dmi.product.sku: SKU dmi.product.version: System Version dmi.sys.vendor: ASUS version.compiz: compiz N/A version.libdrm2: libdrm2 2.4.120-2build1 version.libgl1-mesa-dri: libgl1-mesa-dri 24.0.9-0ubuntu0.1 version.libgl1-mesa-glx: libgl1-mesa-glx 23.0.4-0ubuntu1~23.04.1 version.xserver-xorg-core: xserver-xorg-core 2:21.1.12-1ubuntu1 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A version.xserver-xorg-video-ati: xserver-xorg-video-ati N/A version.xserver-xorg-video-intel: xserver-xorg-video-intel N/A version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.17-2build1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/2077612/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
