Re: KVM got slow after adding more physical memory to host

Avi Kivity
2011-09-06T16:06:38Z

On 09/06/2011 07:01 PM, Nikola Ciprich wrote:
> > 404
> ouch, dumb me :-/
> http://nelide.cz/downloads/nik/trace.dat.bz2
> sorry
> n.
>

qemu-kvm-4618 [000] 13698.803169: kvm_emulate_insn:
0:806edb12: rep outsw
qemu-kvm-4618 [000] 13698.803170: kvm_pio:
pio_write at 0x1f0 size 2 count 1
qemu-kvm-4618 [000] 13698.803171: kvm_userspace_exit: reason
KVM_EXIT_IO (2)
qemu-kvm-4618 [000] 13698.803186: kvm_entry: vcpu 0
qemu-kvm-4618 [000] 13698.803189: kvm_exit: reason
IO_INSTRUCTION rip 0x806edb12 info 1f00031 0

qemu-kvm-4618 [000] 13698.803191: kvm_emulate_insn:
0:806edb12: rep outsw
qemu-kvm-4618 [000] 13698.803192: kvm_pio:
pio_write at 0x1f0 size 2 count 1
qemu-kvm-4618 [000] 13698.803193: kvm_userspace_exit: reason
KVM_EXIT_IO (2)
qemu-kvm-4618 [000] 13698.803195: kvm_entry: vcpu 0
qemu-kvm-4618 [000] 13698.803198: kvm_exit: reason
IO_INSTRUCTION rip 0x806edb12 info 1f00031 0

One of your guests is using IDE PIO instead of DMA. Switch it back to DMA.

Gleb, is rep/outsw our pio regression or was it another instruction?

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error compiling committee.c: too many arguments to function