注意：我已经在问题的底部包含了我能想到的所有系统详细信息。
几周来，当我的笔记本电脑使用外部屏幕对接时，我一直在处理系统缓慢的症状。移动窗口时断时续，任一屏幕上的视频都会掉帧并停顿，屏幕撕裂非常严重（这可能是一个转移注意力的问题，我读过这是一个众所周知的问题）。
对接时设置：笔记本电脑屏幕禁用，一台 4k 显示器纵向，一台 4k 显示器横向。
我安装并运行了 glmark2 3 次：一次是在没有连接扩展坞的笔记本电脑屏幕上，一次是按照描述的屏幕，一次是屏幕均处于横向模式。完整输出如下，但分数为：~2000、~250、~2000。
我的故障排除能力即将结束，但我还无法找到与这些症状相匹配的问题的任何好的参考资料。感觉不像是码头问题，因为当两个屏幕都处于横向模式时，不会出现 glmark2 面包屑症状；但我愿意接受建议，将问题范围缩小到可能的码头问题。
接受任何命令输出请求或尝试稳定配置的建议。我不知道下一步该去哪里，我一直在搜索视频驱动程序博客条目、发行版错误列表、内核错误列表等，但都无济于事。我只是希望能够旋转我的第二个屏幕，而系统不会慢得像爬行一样。
快速说明：您会注意到 glmark 测试默认针对 Intel HD 630 显示驱动程序。通过使用“env DRI_PRIME=1 glmark2”芯片运行来强制使用分立的 Vega M 会产生类似的分数结果，并且与垂直方向的显示器存在差异。
系统信息：
Device: Dell 9575 2-in-1 laptop
Dock: Dell TB-16
Screens: Dell U2718Q, 3840x2160, 60Hz native
inxi -Fzx
System:
Host: donatello Kernel: 4.18.20-041820-generic x86_64 bits: 64
compiler: gcc v: 8.2.0 Desktop: Cinnamon 4.0.10
Distro: Linux Mint 19.1 Tessa base: Ubuntu 18.04 bionic
Machine:
Type: Laptop System: Dell product: XPS 15 9575 v: N/A serial: <filter>
Mobo: Dell model: 0DV9HH v: A00 serial: <filter> UEFI: Dell v: 1.2.0
date: 10/10/2018
Battery:
ID-1: BAT0 charge: 72.6 Wh condition: 72.6/75.0 Wh (97%)
model: BYD DELL TMFYT8B status: Full
Device-1: hid-f4:1b:a1:34:ad:0e-battery model: Trackpad
charge: N/A status: Discharging
CPU:
Topology: Quad Core model: Intel Core i7-8706G bits: 64 type: MT MCP
arch: Kaby Lake rev: 9 L2 cache: 8192 KiB
flags: lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 49536
Speed: 800 MHz min/max: 800/4100 MHz Core speeds (MHz): 1: 800 2: 800
3: 800 4: 800 5: 800 6: 800 7: 800 8: 800
Graphics:
Device-1: Intel vendor: Dell driver: i915 v: kernel bus ID: 00:02.0
Device-2: AMD Polaris 22 [Radeon RX Vega M GL] driver: amdgpu v: kernel
bus ID: 01:00.0
Display: x11 server: X.Org 1.19.6 driver: amdgpu,ati,modesetting
unloaded: fbdev,vesa resolution: 3840x2160~60Hz, 3840x2160~60Hz
OpenGL: renderer: Mesa DRI Intel HD Graphics 630 (Kaby Lake GT2)
v: 4.5 Mesa 18.2.8 direct render: Yes
Audio:
Device-1: Intel CM238 HD Audio vendor: Dell driver: snd_hda_intel
v: kernel bus ID: 00:1f.3
Device-2: Realtek type: USB driver: snd-usb-audio bus ID: 3-1.5:4
Sound Server: ALSA v: k4.18.20-041820-generic
Network:
Device-1: Intel Wireless 8265 / 8275 driver: iwlwifi v: kernel port: e000
bus ID: 02:00.0
IF: wlp2s0 state: up mac: <filter>
Device-2: Realtek type: USB driver: r8152 bus ID: 4-1.2:4
IF: enxc8f750c5b27b state: up speed: 1000 Mbps duplex: full mac: <filter>
Drives:
Local Storage: total: 476.94 GiB used: 89.55 GiB (18.8%)
ID-1: /dev/nvme0n1 vendor: Toshiba model: KXG60ZNV512G NVMe 512GB
size: 476.94 GiB
Partition:
ID-1: / size: 467.96 GiB used: 44.77 GiB (9.6%) fs: ext4
dev: /dev/nvme0n1p2
ID-2: swap-1 size: 2.00 GiB used: 0 KiB (0.0%) fs: swap dev: /dev/dm-0
Sensors:
System Temperatures: cpu: 60.5 C mobo: N/A gpu: amdgpu temp: 51 C
Fan Speeds (RPM): N/A
Info:
Processes: 313 Uptime: 13h 13m Memory: 15.39 GiB used: 3.63 GiB (23.6%)
Init: systemd runlevel: 5 Compilers: gcc: 7.3.0 clang: 6.0.0-1ubuntu2
Shell: bash v: 4.4.19 inxi: 3.0.27
。
Laptop screen only:
=======================================================
glmark2 2014.03+git20150611.fa71af2d
=======================================================
OpenGL Information
GL_VENDOR: Intel Open Source Technology Center
GL_RENDERER: Mesa DRI Intel(R) HD Graphics 630 (Kaby Lake GT2)
GL_VERSION: 3.0 Mesa 18.2.8
=======================================================
[build] use-vbo=false: FPS: 2669 FrameTime: 0.375 ms
[build] use-vbo=true: FPS: 2763 FrameTime: 0.362 ms
[texture] texture-filter=nearest: FPS: 2893 FrameTime: 0.346 ms
[texture] texture-filter=linear: FPS: 2837 FrameTime: 0.352 ms
[texture] texture-filter=mipmap: FPS: 2775 FrameTime: 0.360 ms
[shading] shading=gouraud: FPS: 2534 FrameTime: 0.395 ms
[shading] shading=blinn-phong-inf: FPS: 2551 FrameTime: 0.392 ms
[shading] shading=phong: FPS: 2348 FrameTime: 0.426 ms
[shading] shading=cel: FPS: 2261 FrameTime: 0.442 ms
[bump] bump-render=high-poly: FPS: 1742 FrameTime: 0.574 ms
[bump] bump-render=normals: FPS: 2947 FrameTime: 0.339 ms
[bump] bump-render=height: FPS: 2849 FrameTime: 0.351 ms
[effect2d] kernel=0,1,0;1,-4,1;0,1,0;: FPS: 1738 FrameTime: 0.575 ms
[effect2d] kernel=1,1,1,1,1;1,1,1,1,1;1,1,1,1,1;: FPS: 1117 FrameTime: 0.895 ms
[pulsar] light=false:quads=5:texture=false: FPS: 2562 FrameTime: 0.390 ms
[desktop] blur-radius=5:effect=blur:passes=1:separable=true:windows=4: FPS: 1066 FrameTime: 0.938 ms
[desktop] effect=shadow:windows=4: FPS: 1609 FrameTime: 0.622 ms
[buffer] columns=200:interleave=false:update-dispersion=0.9:update-fraction=0.5:update-method=map: FPS: 891 FrameTime: 1.122 ms
[buffer] columns=200:interleave=false:update-dispersion=0.9:update-fraction=0.5:update-method=subdata: FPS: 858 FrameTime: 1.166 ms
[buffer] columns=200:interleave=true:update-dispersion=0.9:update-fraction=0.5:update-method=map: FPS: 980 FrameTime: 1.020 ms
[ideas] speed=duration: FPS: 2073 FrameTime: 0.482 ms
[jellyfish] <default>: FPS: 2044 FrameTime: 0.489 ms
[terrain] <default>: FPS: 249 FrameTime: 4.016 ms
[shadow] <default>: FPS: 2013 FrameTime: 0.497 ms
[refract] <default>: FPS: 591 FrameTime: 1.692 ms
[conditionals] fragment-steps=0:vertex-steps=0: FPS: 2748 FrameTime: 0.364 ms
[conditionals] fragment-steps=5:vertex-steps=0: FPS: 2606 FrameTime: 0.384 ms
[conditionals] fragment-steps=0:vertex-steps=5: FPS: 2777 FrameTime: 0.360 ms
[function] fragment-complexity=low:fragment-steps=5: FPS: 2784 FrameTime: 0.359 ms
[function] fragment-complexity=medium:fragment-steps=5: FPS: 2837 FrameTime: 0.352 ms
[loop] fragment-loop=false:fragment-steps=5:vertex-steps=5: FPS: 2839 FrameTime: 0.352 ms
[loop] fragment-steps=5:fragment-uniform=false:vertex-steps=5: FPS: 2794 FrameTime: 0.358 ms
[loop] fragment-steps=5:fragment-uniform=true:vertex-steps=5: FPS: 2682 FrameTime: 0.373 ms
=======================================================
glmark2 Score: 2152
=======================================================
。
External Screens, both horizontal orientation
=======================================================
glmark2 2014.03+git20150611.fa71af2d
=======================================================
OpenGL Information
GL_VENDOR: Intel Open Source Technology Center
GL_RENDERER: Mesa DRI Intel(R) HD Graphics 630 (Kaby Lake GT2)
GL_VERSION: 3.0 Mesa 18.2.8
=======================================================
[build] use-vbo=false: FPS: 3246 FrameTime: 0.308 ms
[build] use-vbo=true: FPS: 3523 FrameTime: 0.284 ms
[texture] texture-filter=nearest: FPS: 3227 FrameTime: 0.310 ms
[texture] texture-filter=linear: FPS: 3244 FrameTime: 0.308 ms
[texture] texture-filter=mipmap: FPS: 3205 FrameTime: 0.312 ms
[shading] shading=gouraud: FPS: 2778 FrameTime: 0.360 ms
[shading] shading=blinn-phong-inf: FPS: 2846 FrameTime: 0.351 ms
[shading] shading=phong: FPS: 2566 FrameTime: 0.390 ms
[shading] shading=cel: FPS: 2585 FrameTime: 0.387 ms
[bump] bump-render=high-poly: FPS: 1874 FrameTime: 0.534 ms
[bump] bump-render=normals: FPS: 3372 FrameTime: 0.297 ms
[bump] bump-render=height: FPS: 3194 FrameTime: 0.313 ms
[effect2d] kernel=0,1,0;1,-4,1;0,1,0;: FPS: 1829 FrameTime: 0.547 ms
[effect2d] kernel=1,1,1,1,1;1,1,1,1,1;1,1,1,1,1;: FPS: 1128 FrameTime: 0.887 ms
[pulsar] light=false:quads=5:texture=false: FPS: 2754 FrameTime: 0.363 ms
[desktop] blur-radius=5:effect=blur:passes=1:separable=true:windows=4: FPS: 1082 FrameTime: 0.924 ms
[desktop] effect=shadow:windows=4: FPS: 1781 FrameTime: 0.561 ms
[buffer] columns=200:interleave=false:update-dispersion=0.9:update-fraction=0.5:update-method=map: FPS: 1007 FrameTime: 0.993 ms
[buffer] columns=200:interleave=false:update-dispersion=0.9:update-fraction=0.5:update-method=subdata: FPS: 482 FrameTime: 2.075 ms
[buffer] columns=200:interleave=true:update-dispersion=0.9:update-fraction=0.5:update-method=map: FPS: 642 FrameTime: 1.558 ms
[ideas] speed=duration: FPS: 664 FrameTime: 1.506 ms
[jellyfish] <default>: FPS: 1929 FrameTime: 0.518 ms
[terrain] <default>: FPS: 226 FrameTime: 4.425 ms
[shadow] <default>: FPS: 1759 FrameTime: 0.569 ms
[refract] <default>: FPS: 371 FrameTime: 2.695 ms
[conditionals] fragment-steps=0:vertex-steps=0: FPS: 2127 FrameTime: 0.470 ms
[conditionals] fragment-steps=5:vertex-steps=0: FPS: 2527 FrameTime: 0.396 ms
[conditionals] fragment-steps=0:vertex-steps=5: FPS: 2727 FrameTime: 0.367 ms
[function] fragment-complexity=low:fragment-steps=5: FPS: 2402 FrameTime: 0.416 ms
[function] fragment-complexity=medium:fragment-steps=5: FPS: 2642 FrameTime: 0.379 ms
[loop] fragment-loop=false:fragment-steps=5:vertex-steps=5: FPS: 2675 FrameTime: 0.374 ms
[loop] fragment-steps=5:fragment-uniform=false:vertex-steps=5: FPS: 2280 FrameTime: 0.439 ms
[loop] fragment-steps=5:fragment-uniform=true:vertex-steps=5: FPS: 1708 FrameTime: 0.585 ms
=======================================================
glmark2 Score: 2133
=======================================================
。
External Screens, one horizontal, one vertical orientation
=======================================================
glmark2 2014.03+git20150611.fa71af2d
=======================================================
OpenGL Information
GL_VENDOR: Intel Open Source Technology Center
GL_RENDERER: Mesa DRI Intel(R) HD Graphics 630 (Kaby Lake GT2)
GL_VERSION: 3.0 Mesa 18.2.8
=======================================================
[build] use-vbo=false: FPS: 248 FrameTime: 4.032 ms
[build] use-vbo=true: FPS: 351 FrameTime: 2.849 ms
[texture] texture-filter=nearest: FPS: 315 FrameTime: 3.175 ms
[texture] texture-filter=linear: FPS: 332 FrameTime: 3.012 ms
[texture] texture-filter=mipmap: FPS: 333 FrameTime: 3.003 ms
[shading] shading=gouraud: FPS: 293 FrameTime: 3.413 ms
[shading] shading=blinn-phong-inf: FPS: 311 FrameTime: 3.215 ms
[shading] shading=phong: FPS: 286 FrameTime: 3.497 ms
[shading] shading=cel: FPS: 266 FrameTime: 3.759 ms
[bump] bump-render=high-poly: FPS: 229 FrameTime: 4.367 ms
[bump] bump-render=normals: FPS: 344 FrameTime: 2.907 ms
[bump] bump-render=height: FPS: 319 FrameTime: 3.135 ms
[effect2d] kernel=0,1,0;1,-4,1;0,1,0;: FPS: 234 FrameTime: 4.274 ms
[effect2d] kernel=1,1,1,1,1;1,1,1,1,1;1,1,1,1,1;: FPS: 139 FrameTime: 7.194 ms
[pulsar] light=false:quads=5:texture=false: FPS: 287 FrameTime: 3.484 ms
[desktop] blur-radius=5:effect=blur:passes=1:separable=true:windows=4: FPS: 134 FrameTime: 7.463 ms
[desktop] effect=shadow:windows=4: FPS: 202 FrameTime: 4.950 ms
[buffer] columns=200:interleave=false:update-dispersion=0.9:update-fraction=0.5:update-method=map: FPS: 57 FrameTime: 17.544 ms
[buffer] columns=200:interleave=false:update-dispersion=0.9:update-fraction=0.5:update-method=subdata: FPS: 102 FrameTime: 9.804 ms
[buffer] columns=200:interleave=true:update-dispersion=0.9:update-fraction=0.5:update-method=map: FPS: 60 FrameTime: 16.667 ms
[ideas] speed=duration: FPS: 179 FrameTime: 5.587 ms
[jellyfish] <default>: FPS: 227 FrameTime: 4.405 ms
[terrain] <default>: FPS: 67 FrameTime: 14.925 ms
[shadow] <default>: FPS: 224 FrameTime: 4.464 ms
[refract] <default>: FPS: 79 FrameTime: 12.658 ms
[conditionals] fragment-steps=0:vertex-steps=0: FPS: 271 FrameTime: 3.690 ms
[conditionals] fragment-steps=5:vertex-steps=0: FPS: 263 FrameTime: 3.802 ms
[conditionals] fragment-steps=0:vertex-steps=5: FPS: 271 FrameTime: 3.690 ms
[function] fragment-complexity=low:fragment-steps=5: FPS: 275 FrameTime: 3.636 ms
[function] fragment-complexity=medium:fragment-steps=5: FPS: 265 FrameTime: 3.774 ms
[loop] fragment-loop=false:fragment-steps=5:vertex-steps=5: FPS: 277 FrameTime: 3.610 ms
[loop] fragment-steps=5:fragment-uniform=false:vertex-steps=5: FPS: 271 FrameTime: 3.690 ms
[loop] fragment-steps=5:fragment-uniform=true:vertex-steps=5: FPS: 273 FrameTime: 3.663 ms
=======================================================
glmark2 Score: 235
=======================================================