Yes, I can reproduce this. Also, interestingly, with the -icount version when I typed 'exit' to quit the guest I got this abort:
qemu: fatal: cpu_io_recompile: could not find TB for pc=0x7fcd0aae636e EAX=c88053a4 EBX=00000069 ECX=c00211a4 EDX=00000000 ESI=c7812180 EDI=c78126f0 EBP=0000000f ESP=c7a0de44 EIP=c11ada30 EFL=00000287 [--S--PC] CPL=0 II=0 A20=1 SMM=0 HLT=0 ES =007b 00000000 ffffffff 00cff300 DPL=3 DS [-WA] CS =0060 00000000 ffffffff 00cf9a00 DPL=0 CS32 [-R-] SS =0068 00000000 ffffffff 00c09300 DPL=0 DS [-WA] DS =007b 00000000 ffffffff 00cff300 DPL=3 DS [-WA] FS =0000 00000000 00000000 00000000 GS =0033 080a130c ffffffff 00dff300 DPL=3 DS [-WA] LDT=0000 00000000 00000000 00008200 DPL=0 LDT TR =0080 c12fbe60 0000206b 00008900 DPL=0 TSS32-avl GDT= c12f6000 000000ff IDT= ffffc000 000007ff CR0=8005003b CR2=09d40ffc CR3=07a08000 CR4=00000690 DR0=00000000 DR1=00000000 DR2=00000000 DR3=00000000 DR6=ffff0ff0 DR7=00000400 CCS=c8800000 CCD=c8805200 CCO=SUBL EFER=0000000000000000 FCW=037f FSW=0000 [ST=0] FTW=00 MXCSR=00001f80 FPR0=0000000000000000 0000 FPR1=0000000000000000 0000 FPR2=0000000000000000 0000 FPR3=0000000000000000 0000 FPR4=0000000000000000 0000 FPR5=0000000000000000 0000 FPR6=0000000000000000 0000 FPR7=ec00000000000000 4006 XMM00=00000000000000000000000000000000 XMM01=00000000000000000000000000000000 XMM02=00000000000000000000000000000000 XMM03=00000000000000000000000000000000 XMM04=00000000000000000000000000000000 XMM05=00000000000000000000000000000000 XMM06=00000000000000000000000000000000 XMM07=00000000000000000000000000000000 Aborted (core dumped) ** Changed in: qemu Status: New => Confirmed -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1774677 Title: -icount increases boot time by >10x Status in QEMU: Confirmed Bug description: When I specify the -icount option, some guest operations such as booting a Linux kernel take more than 10 times longer than otherwise. For example, the following will boot Aboriginal Linux to the login prompt about 6 seconds on my system (using TCG, not KVM): wget http://landley.net/aboriginal/downloads/old/binaries/1.4.5/system-image-i686.tar.gz gunzip <system-image-i686.tar.gz | tar xfv - cd system-image-i686 sh run-emulator.sh If I replace the last line with QEMU_EXTRA="-icount shift=auto" sh run-emulator.sh booting to the login prompt takes about 1 minute 20 seconds. I have tried different values for "shift" other than the "auto" used above, but have not been able to find one that gives reasonable performance. Specifying "sleep=off" also did not help. During the slow boots, qemu appears to spend most of its time sleeping, not using the host CPU. I see this with multiple versions of qemu, including current git sources (c181ddaa176856b3cd2dfd12bbcf25fa9c884a97), and on multiple host OSes, including Debian 9 on x86_64. To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1774677/+subscriptions