Loss of detail from kthreads
julian at elischer.org
Tue Nov 13 17:25:14 PST 2007
Kris Kennaway wrote:
> Since the conversion from kprocs to kthreads there is a loss of
> precision in how kernel process names are reported, because they now
> mostly report the kproc name which is very generic.
> e.g. if you only use top -S then you only have "idle", "intr" processes,
> etc. You have to use top -SH, but then you also see the userland
> threads, and there might be hundreds of them obscuring the kernel
there were dozens of interrupt threads obscuring things too.
now there aren't.
Sounds like you'd like an option -K to just look at the kernel?
> threads. Also, ps now only displays the kproc:
well if you ask it to it'' show the kthreads.
root at trafmon1:ps -opid,tdnam,comm -xH
PID THRDNAME COMMAND
5 thread taskq
9 kqueue taskq
11 idle: cpu3 idle/idle: cpu3
11 idle: cpu2 idle/idle: cpu2
11 idle: cpu1 idle/idle: cpu1
11 idle: cpu0 idle/idle: cpu0
12 swi4: clock sio intr/swi4: clock sio
12 swi3: vm intr/swi3: vm
12 swi1: net intr/swi1: net
12 swi5: + intr/swi5: +
12 swi6: Giant task intr/swi6: Giant task
12 swi6: task queue intr/swi6: task queue
12 swi2: cambio intr/swi2: cambio
12 irq9: acpi0 intr/irq9: acpi0
12 swi0: uart sio intr/swi0: uart sio
12 irq14: ata0 intr/irq14: ata0
12 irq15: ata1 intr/irq15: ata1
12 irq28: bge0 intr/irq28: bge0
12 irq29: bge1 intr/irq29: bge1
12 irq20: fxp0 intr/irq20: fxp0
12 irq1: atkbd0 intr/irq1: atkbd0
12 irq12: psm0 intr/irq12: psm0
if you want that done by default someway then let's hear
what you'd like to do..
My plan is to add a -K option that is the equivalent of -SH in top
and the above in ps. I haven't investigated allthe versions of ps
yet to decide what it should be.
we could make -S in top show all the kernel threads if you wanted to..
but that's a bikeshed I'll let you fight..
it would be relatively trivial change to do this..
> root 12 100.0 0.0 0 136 ?? RL Sat01PM 6:28.30 [intr]
> so you can't see which interrupt(s) are using CPU.
> Finally, I noticed that DDB only displays the kproc name in e.g. allpcpu:
> cpuid = 1
> curthread = 0xcb41da50: pid 12 "intr"
> curpcb = 0xe992cd90
> fpcurthread = none
> idlethread = 0xc67b7420: pid 11 "idle"
> APIC ID = 1
> currentldt = 0x50
> Probably other things are also affected. All of these make kernel
> analysis and debugging much less convenient, so this seems to me to be a
> step backwards. Are you still working on fixing these issues?
yes but distracted by $DAYJOB
ddb shows the thread name if you do 'ps'
I think pcpu should always show the thread name if it exists.
More information about the freebsd-current