I have a similar problem, and the problem goes away if I remove the "-serial pty" device from my command line:
/home/mrhines/qemu/x86_64-softmmu/qemu-system-x86_64 /kvm_repo/cb/vmbase -serial pty
Such a simple command line, but QEMU seizes up and slows to a crawl and the host CPU is spinning at 100%
I have a similar problem, and the problem goes away if I remove the "-serial pty" device from my command line:
/home/mrhines/ qemu/x86_ 64-softmmu/ qemu-system- x86_64 /kvm_repo/cb/vmbase -serial pty
Such a simple command line, but QEMU seizes up and slows to a crawl and the host CPU is spinning at 100%