在Ubuntu 16.04电脑上,我发现
我生成了一个性能报告:
我不知道如何复现。重新启动后问题就消失了。 发生了什么事?
kworker
持续占用80%的CPU。我生成了一个性能报告:
sudo apt-get install linux-tools-common linux-tools-$(uname -r)
- 记录所有CPU上10秒钟的回溯信息:
sudo perf record -g -a sleep 10
- 使用
sudo perf report
查看报告。
Samples: 47K of event 'cycles:ppp', Event count (approx.): 38282161158
Children Self Command Shared Object Symbol
+ 77.04% 0.00% kworker/3:3 [kernel.kallsyms] [k] ret_from_fork
+ 77.04% 0.00% kworker/3:3 [kernel.kallsyms] [k] kthread
+ 77.04% 0.00% kworker/3:3 [kernel.kallsyms] [k] worker_thread
+ 77.00% 0.13% kworker/3:3 [kernel.kallsyms] [k] process_one_work
+ 76.26% 0.04% kworker/3:3 [kernel.kallsyms] [k] rpm_idle
+ 75.98% 0.06% kworker/3:3 [kernel.kallsyms] [k] rpm_suspend
+ 75.97% 0.03% kworker/3:3 [kernel.kallsyms] [k] pm_runtime_work
+ 75.84% 0.03% kworker/3:3 [kernel.kallsyms] [k] __rpm_callback
+ 75.82% 0.01% kworker/3:3 [kernel.kallsyms] [k] usb_runtime_idle
+ 75.76% 0.00% kworker/3:3 [kernel.kallsyms] [k] __pm_runtime_suspend
+ 75.64% 0.00% kworker/3:3 [kernel.kallsyms] [k] rpm_callback
+ 75.61% 0.04% kworker/3:3 [kernel.kallsyms] [k] usb_runtime_suspend
+ 75.51% 0.03% kworker/3:3 [kernel.kallsyms] [k] usb_suspend_both
+ 73.51% 0.15% kworker/3:3 [kernel.kallsyms] [k] usb_control_msg
+ 71.97% 0.14% kworker/3:3 [kernel.kallsyms] [k] usb_start_wait_urb
+ 68.38% 0.05% kworker/3:3 [kernel.kallsyms] [k] usb_submit_urb
+ 68.33% 0.30% kworker/3:3 [kernel.kallsyms] [k] usb_submit_urb.part.8
+ 67.75% 0.82% kworker/3:3 [kernel.kallsyms] [k] usb_hcd_submit_urb
+ 60.96% 60.41% kworker/3:3 [kernel.kallsyms] [k] xhci_hub_control
+ 55.99% 0.12% kworker/3:3 [kernel.kallsyms] [k] hub_suspend
+ 54.97% 0.04% kworker/3:3 [kernel.kallsyms] [k] set_port_feature
+ 19.36% 0.01% kworker/3:3 [kernel.kallsyms] [k] usb_resume_interface.isra.8
+ 19.35% 0.02% kworker/3:3 [kernel.kallsyms] [k] hub_resume
+ 19.32% 0.14% kworker/3:3 [kernel.kallsyms] [k] hub_activate
+ 18.78% 0.08% kworker/3:3 [kernel.kallsyms] [k] hub_ext_port_status
+ 11.13% 0.00% ksoftirqd/3 [kernel.kallsyms] [k] ret_from_fork
+ 11.13% 0.00% ksoftirqd/3 [kernel.kallsyms] [k] kthread
+ 10.44% 0.51% ksoftirqd/3 [kernel.kallsyms] [k] smpboot_thread_fn
我不知道如何复现。重新启动后问题就消失了。 发生了什么事?