Re: Kernel is using a lot of CPU (was: Re: test)
- Reply: Eugene Grosbein : "Re: Kernel is using a lot of CPU"
- In reply to: Nikos Vassiliadis : "Re: Kernel is using a lot of CPU (was: Re: test)"
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Date: Mon, 30 Jan 2023 14:27:30 UTC
> Sent: Monday, January 30, 2023 at 3:37 PM > From: "Nikos Vassiliadis" <nvass@gmx.com> > To: "Mike Karels" <mike@karels.net> > Cc: freebsd-stable@freebsd.org > Subject: Re: Kernel is using a lot of CPU (was: Re: test) > > > > > Sent: Monday, January 30, 2023 at 3:27 PM > > From: "Mike Karels" <mike@karels.net> > > To: "Nikos Vassiliadis" <nvass@gmx.com> > > Cc: freebsd-stable@freebsd.org > > Subject: Re: Kernel is using a lot of CPU (was: Re: test) > > > > On 30 Jan 2023, at 5:03, Nikos Vassiliadis wrote: > > > > >> Hi, > > >> > > >> I just rebooted a system of mine and it seems that the kernel is constantly doing something. How could I debug this? > > >> I am thinking of rebooting it tonight > > >> > > >> root@aurora:~ # top -S -b > > >> last pid: 2196; load averages: 1.00, 1.00, 1.00 up 0+01:54:34 12:41:35 > > >> 72 processes: 2 running, 69 sleeping, 1 waiting > > >> CPU: 0.0% user, 0.0% nice, 24.6% system, 0.0% interrupt, 75.3% idle > > >> Mem: 46M Active, 171M Inact, 1429M Wired, 14G Free > > >> ARC: 919M Total, 354M MFU, 487M MRU, 6912K Anon, 8726K Header, 63M Other > > >> 234M Compressed, 610M Uncompressed, 2.60:1 Ratio > > >> Swap: 16G Total, 16G Free > > >> > > >> PID USERNAME THR PRI NICE SIZE RES STATE C TIME WCPU COMMAND > > >> 11 root 4 155 ki31 0B 64K RUN 0 345:06 314.31% idle > > >> 0 root 49 -16 - 0B 784K swapin 1 112:27 99.85% kernel > > >> 30 root 319 -16 - 0B 5120K spa->s 3 0:06 0.00% zpool-aurora-os > > >> 1157 root 1 20 0 176M 150M select 2 0:05 0.00% smbd > > >> 1154 root 1 20 0 175M 150M select 2 0:05 0.00% smbd > > >> > > >> This is a 12.4-RELEASE system. > > >> > > >> Thanks for any ideas, > > >> Nikos > > >> > > >> > > >> > > > > > > Sending the email again with the correct subject > > > > You could add -H to the top command, which will show kernel threads within > > the kernel process. > > > > Mike > > > > > > Thanks Mike, > > A kernel thread named acpi_task_n seems to be the source of the problem. This system is rather old and was ok running 12.2-REL. Maybe some update to the ACPI code?. What could I try next? > > nik@aurora:~ % top -H -S -b > last pid: 2529; load averages: 1.03, 1.03, 1.00 up 0+04:43:45 15:30:46 > 840 threads: 6 running, 820 sleeping, 14 waiting > CPU: 0.0% user, 0.0% nice, 24.6% system, 0.0% interrupt, 75.3% idle > Mem: 29M Active, 192M Inact, 1717M Wired, 13G Free > ARC: 1182M Total, 475M MFU, 608M MRU, 7744K Anon, 12M Header, 79M Other > 312M Compressed, 782M Uncompressed, 2.51:1 Ratio > Swap: 16G Total, 16G Free > > PID USERNAME PRI NICE SIZE RES STATE C TIME WCPU COMMAND > 11 root 155 ki31 0B 64K CPU3 3 272:53 100.00% idle{idle: cpu3} > 11 root 155 ki31 0B 64K RUN 0 260:10 81.15% idle{idle: cpu0} > 0 root 8 - 0B 784K - 3 141:30 76.76% kernel{acpi_task_2} > 11 root 155 ki31 0B 64K CPU1 1 212:51 74.66% idle{idle: cpu1} > 11 root 155 ki31 0B 64K RUN 2 108:52 51.86% idle{idle: cpu2} > 0 root 8 - 0B 784K CPU2 2 116:25 24.27% kernel{acpi_task_0} > 2324 root 20 0 177M 151M select 3 0:03 0.10% smbd{smbd} > 0 root 8 - 0B 784K - 0 21:08 0.00% kernel{acpi_task_1} > 0 root -16 - 0B 784K swapin 2 0:53 0.00% kernel{swapper} > > > > > > 12.4 autoloaded acpi_wmi with dubious results: Autoloading module: acpi_wmi acpi_wmi0: <ACPI-WMI mapping> on acpi0 acpi_wmi0: cannot find EC device device_attach: acpi_wmi0 attach returned 6 acpi_wmi0: <ACPI-WMI mapping> on acpi0 acpi_wmi0: cannot find EC device device_attach: acpi_wmi0 attach returned 6 12.2 did not autoload it.