windows PIO question
Hello everybody,
I'm a bit confused regarding windows guests and PIO.. some time ago, I was trying to find out, why one of my windows guests was running terribly slow. After checking the trace-cmd output, Avi stated that windows were using PIO instead of DMA, after changing that, windows indeed got a lot faster. I didn't check traces
after that, but I'm now testing host with two windows 2003 guests, and checking the
trac-cmd output, I see a lot of kvm_pio calls.
While windows don't seem to be running particularly slow, they're not especially fast either, and I'm wandering whether this could be related. But checking IDE bus in guests, they seem to be using DMA which confuses me...
so my questions is, what are the kvm_pio operations I see in traces, and how can I tell what is OK and what is wrong, regarding disks DMA/PIO?
If somebody could shed some light on this for me, I'd be very grateful...
Thanks a lot in advance
with best regards
nikola ciprich
Signature · 14 lines
------------------------------------- Ing. Nikola CIPRICH LinuxBox.cz, s.r.o. 28. rijna 168, 709 01 Ostrava tel.: +420 596 603 142 fax: +420 596 621 273 mobil: +420 777 093 799 www.linuxbox.cz mobil servis: +420 737 238 656 email servis: [email protected] -------------------------------------
Quoted 14 lines · Nikola Ciprich
Hello everybody,
I'm a bit confused regarding windows guests and PIO.. some time ago, I was trying to find out, why one of my windows guests was running terribly slow. After checking the trace-cmd output, Avi stated that windows were using PIO instead of DMA, after changing that, windows indeed got a lot faster. I didn't check traces
after that, but I'm now testing host with two windows 2003 guests, and checking the
trac-cmd output, I see a lot ofkvm_piocalls.
While windows don't seem to be running particularly slow, they're not especially fast either, and I'm wandering whether this could be related. But checking IDE bus in guests, they seem to be using DMA which confuses me...
so my questions is, what are thekvm_piooperations I see in traces, and how can I tell what is OK and what is wrong, regarding disks DMA/PIO?
If somebody could shed some light on this for me, I'd be very grateful...
Not all PIO operations are DMA. Provide a trace and we can look.
Signature · 1 line
error compiling committee.c: too many arguments to function
Quoted 1 line
Not all PIO operations are DMA. Provide a trace and we can look.
Hi,
here's snippet:
qemu-kvm-16441 [000] 12887154.698329: kvm_pio: pio_read at 0xc002 size 1 count 1
qemu-kvm-16441 [000] 12887154.698331: kvm_userspace_exit: reason KVM_EXIT_IO (2)
qemu-kvm-16441 [000] 12887154.698331: kvm_fpu: unload
qemu-kvm-16441 [000] 12887154.698337: kvm_entry: vcpu 1
qemu-kvm-16441 [000] 12887154.698338: kvm_exit: [FAILED TO PARSE] exit_reason=30 guest_rip=0xfffff88000dabca3 isa=1 info1=3221356552 info2=0
qemu-kvm-16441 [000] 12887154.698339: kvm_emulate_insn: [FAILED TO PARSE] rip=18446735827386678435 csbase=0 len=1 insn=<EC><C3><CC><CC><CC><CC><CC><CC><CC>^O<B7><D1>f<ED><C3> flags=9 failed=0
qemu-kvm-16441 [000] 12887154.698340: kvm_pio: pio_read at 0xc002 size 1 count 1
qemu-kvm-16441 [000] 12887154.698340: kvm_userspace_exit: reason KVM_EXIT_IO (2)
qemu-kvm-16441 [000] 12887154.698343: kvm_entry: vcpu 1
qemu-kvm-16441 [000] 12887154.698344: kvm_exit: [FAILED TO PARSE] exit_reason=30 guest_rip=0xfffff88000dabdbd isa=1 info1=3221225472 info2=0
qemu-kvm-16441 [000] 12887154.698345: kvm_pio: pio_write at 0xc000 size 1 count 1
qemu-kvm-16441 [000] 12887154.698346: kvm_userspace_exit: reason KVM_EXIT_IO (2)
qemu-kvm-16441 [000] 12887154.698348: kvm_entry: vcpu 1
qemu-kvm-16441 [000] 12887154.698349: kvm_exit: [FAILED TO PARSE] exit_reason=30 guest_rip=0xfffff88000dabdbd isa=1 info1=3221356544 info2=0
qemu-kvm-16441 [000] 12887154.698349: kvm_pio: pio_write at 0xc002 size 1 count 1
qemu-kvm-16441 [000] 12887154.698350: kvm_userspace_exit: reason KVM_EXIT_IO (2)
qemu-kvm-16441 [000] 12887154.698352: kvm_entry: vcpu 1
qemu-kvm-16441 [000] 12887154.698353: kvm_exit: [FAILED TO PARSE] exit_reason=30 guest_rip=0xfffff88000dabca3 isa=1 info1=32964616 info2=0
qemu-kvm-16441 [000] 12887154.698354: kvm_emulate_insn: [FAILED TO PARSE] rip=18446735827386678435 csbase=0 len=1 insn=<EC><C3><CC><CC><CC><CC><CC><CC><CC>^O<B7><D1>f<ED><C3> flags=9 failed=0
qemu-kvm-16441 [000] 12887154.698354: kvm_pio: pio_read at 0x1f7 size 1 count 1
qemu-kvm-16441 [000] 12887154.698355: kvm_userspace_exit: reason KVM_EXIT_IO (2)
qemu-kvm-16441 [000] 12887154.698357: kvm_set_irq: gsi 14 level 0 source 0
qemu-kvm-16441 [000] 12887154.698358: kvm_pic_set_irq: chip 1 pin 6 (edge|masked)
qemu-kvm-16441 [000] 12887154.698358: kvm_ioapic_set_irq: pin 14 dst 3 vec=97 (LowPrio|logical|edge)
qemu-kvm-16441 [000] 12887154.698360: kvm_entry: vcpu 1
qemu-kvm-16441 [000] 12887154.698362: kvm_exit: [FAILED TO PARSE] exit_reason=30 guest_rip=0xfffff88000dabca3 isa=1 info1=32964616 info2=0
qemu-kvm-16441 [000] 12887154.698363: kvm_emulate_insn: [FAILED TO PARSE] rip=18446735827386678435 csbase=0 len=1 insn=<EC><C3><CC><CC><CC><CC><CC><CC><CC>^O<B7><D1>f<ED><C3> flags=9 failed=0
qemu-kvm-16441 [000] 12887154.698363: kvm_pio: pio_read at 0x1f7 size 1 count 1n.
Quoted 4 lines
Signature · 2 lines
-- error compiling committee.c: too many arguments to function
Signature · 14 lines
------------------------------------- Ing. Nikola CIPRICH LinuxBox.cz, s.r.o. 28. rijna 168, 709 01 Ostrava tel.: +420 596 603 142 fax: +420 596 621 273 mobil: +420 777 093 799 www.linuxbox.cz mobil servis: +420 737 238 656 email servis: [email protected] -------------------------------------
Quoted 5 lines · Nikola Ciprich
Quoted 1 line
Not all PIO operations are DMA. Provide a trace and we can look.
Hi,
here's snippet:
Quoted 8 lines
qemu-kvm-16441 [000] 12887154.698329: kvm_pio: pio_read at 0xc002 size 1 count 1
qemu-kvm-16441 [000] 12887154.698331: kvm_userspace_exit: reason KVM_EXIT_IO (2)
qemu-kvm-16441 [000] 12887154.698331: kvm_fpu: unload
qemu-kvm-16441 [000] 12887154.698337: kvm_entry: vcpu 1
qemu-kvm-16441 [000] 12887154.698338: kvm_exit: [FAILED TO PARSE] exit_reason=30 guest_rip=0xfffff88000dabca3 isa=1 info1=3221356552 info2=0
qemu-kvm-16441 [000] 12887154.698339: kvm_emulate_insn: [FAILED TO PARSE] rip=18446735827386678435 csbase=0 len=1 insn=<EC><C3><CC><CC><CC><CC><CC><CC><CC>^O<B7><D1>f<ED><C3> flags=9 failed=0
qemu-kvm-16441 [000] 12887154.698340: kvm_pio: pio_read at 0xc002 size 1 count 1That's virtio, not IDE.
Signature · 1 line
error compiling committee.c: too many arguments to function
Quoted 1 line
That's virtio, not IDE.
well, this seems a bit strange to me, the only virtio device I can see is balloon dev, can this be it?
how can I find out which operations are IDE PIO etc? sorry for asking silly questions, but I couldn't find this anywhere in the documentation...
thanks in advance
nik
Quoted 9 lines
Signature · 7 lines
-- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
Signature · 13 lines
------------------------------------- Ing. Nikola CIPRICH LinuxBox.cz, s.r.o. 28. rijna 168, 709 01 Ostrava tel.: +420 596 603 142 fax: +420 596 621 273 mobil: +420 777 093 799 www.linuxbox.cz mobil servis: +420 737 238 656 email servis: [email protected] -------------------------------------