** Also affects: linux (Ubuntu) Importance: Undecided Status: New
-- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1639299 Title: acpi_pad consumes 100% of resources Status in Nvidia: New Status in linux package in Ubuntu: New Bug description: acpi_pad will take up 100% of the CPU resources and slow the system to a crawl. 'rmmod acpi_pad' removes the offender and brings the system response back. PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 20765 root 20 0 0 0 0 R 100.0 0.0 5:07.99 xhpl 20879 root -2 0 0 0 0 R 100.0 0.0 7:12.40 acpi_pad/5 20887 root -2 0 0 0 0 R 100.0 0.0 6:57.72 acpi_pad/13 20891 root -2 0 0 0 0 R 100.0 0.0 7:05.74 acpi_pad/17 20874 root -2 0 0 0 0 R 100.0 0.0 7:15.16 acpi_pad/0 20875 root -2 0 0 0 0 R 100.0 0.0 7:14.76 acpi_pad/1 20876 root -2 0 0 0 0 R 100.0 0.0 7:13.54 acpi_pad/2 20877 root -2 0 0 0 0 R 100.0 0.0 7:13.54 acpi_pad/3 20880 root -2 0 0 0 0 R 100.0 0.0 7:11.44 acpi_pad/6 20881 root -2 0 0 0 0 R 100.0 0.0 7:11.17 acpi_pad/7 20882 root -2 0 0 0 0 R 100.0 0.0 7:05.42 acpi_pad/8 20883 root -2 0 0 0 0 R 100.0 0.0 7:10.80 acpi_pad/9 20884 root -2 0 0 0 0 R 100.0 0.0 7:09.50 acpi_pad/10 20885 root -2 0 0 0 0 R 100.0 0.0 7:09.66 acpi_pad/11 20888 root -2 0 0 0 0 R 100.0 0.0 7:07.30 acpi_pad/14 20889 root -2 0 0 0 0 R 100.0 0.0 7:07.37 acpi_pad/15 20890 root -2 0 0 0 0 R 100.0 0.0 7:05.50 acpi_pad/16 20892 root -2 0 0 0 0 R 100.0 0.0 7:04.40 acpi_pad/18 20893 root -2 0 0 0 0 R 100.0 0.0 7:04.21 acpi_pad/19 20894 root -2 0 0 0 0 R 100.0 0.0 7:03.70 acpi_pad/20 20895 root -2 0 0 0 0 R 100.0 0.0 7:03.63 acpi_pad/21 20896 root -2 0 0 0 0 R 100.0 0.0 7:01.61 acpi_pad/22 20897 root -2 0 0 0 0 R 100.0 0.0 7:01.66 acpi_pad/23 20898 root -2 0 0 0 0 R 100.0 0.0 7:00.80 acpi_pad/24 20899 root -2 0 0 0 0 R 100.0 0.0 7:00.81 acpi_pad/25 20901 root -2 0 0 0 0 R 100.0 0.0 6:58.79 acpi_pad/26 20902 root -2 0 0 0 0 R 100.0 0.0 6:58.96 acpi_pad/27 20903 root -2 0 0 0 0 R 100.0 0.0 6:57.82 acpi_pad/28 20904 root -2 0 0 0 0 R 100.0 0.0 6:57.83 acpi_pad/29 20906 root -2 0 0 0 0 R 100.0 0.0 6:55.54 acpi_pad/31 20886 root -2 0 0 0 0 R 99.7 0.0 7:08.80 acpi_pad/12 20878 root -2 0 0 0 0 R 98.4 0.0 7:12.20 acpi_pad/4 20905 root -2 0 0 0 0 R 98.4 0.0 6:55.85 acpi_pad/30 3049 newrelic 20 0 245800 8388 4724 S 22.3 0.0 0:14.74 nrsysmond 22126 root 20 0 19592 3876 2392 R 6.0 0.0 0:00.99 top 1441 root 39 19 0 0 0 S 3.4 0.0 3:05.47 kipmi0 20720 root 20 0 870276 13080 6208 S 1.6 0.0 0:01.50 collectd 8 root 20 0 0 0 0 S 0.9 0.0 0:03.19 rcu_sched 13 root rt 0 0 0 0 S 0.3 0.0 0:00.03 watchdog/0 This has been seen on the 4.2 and 4.4 kernels. I believe the LINPACK test suite was running in all cases this was seen. However, it occurs pretty infrequently, and I don't know how to reliably recreate the issue. It has only been seen on the DGX-1 Server, not on the DGX Station. I'm not sure if any other systems have seen it. Another data point which may or may not be relevant is that C-states and P-states are enabled. We can workaround this issue by blacklisting the acpi_pad module, or by using the acpi_pad.disable=1 kernel bootarg. What are the implications of disabling acpi_pad are? Googling "acpi_pad uses up all the resource" returns many hits where they all suggest to simply disable it. To manage notifications about this bug go to: https://bugs.launchpad.net/nvidia/+bug/1639299/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp